Page 2
TABLE 11.-Range of accumulation of copper, zinc, molybdenum, and nickel in
parts of plants in mineralized areas [Mineral contents in parts per million]
Copper and inc in dry plants [Warren and others, 1951, p. 920-923]
TABLE 12.-Comparison of the minor-element content, in parts per million, of the coals of the Northern Great Plains province with that of some plants
[0, below limit of detection]
Be. B. Ti. V. Cr Co. NL Cu. ZO. Ga. Ge. Mo. Bn. Y. La..
2.4 112 476 20. 1 9. 3 2.8 8.6 17.4 107
6.3 2.9 2.1 2.1 17.4 14.7
of these elements. A discussion of this process is carried on further in the next section.
In summation, the minor-element content of the coal is in accord with that accumulated by plants and plant debris. In the previous section it was shown that the minor-element content of the coal is related to the minor-element content of the type of source rocks contributing material to the coal-forming swamps. From this it follows that little, if any, change has taken place in the amount of the 15 minor elements in the coal since the time of deposition to the present. In the coalification process a large amount of organic material is lost during its transformation into coal. There probably is also a concomitant loss of minor elements associated with this loss of material.
Special samples such as coalified logs and kettle-bottom coal are treated separately because they offer a basis for more intense speculation about the accumulation of minor elements in coal. There is a general similarity between these samples and the isolated coalified logs found in the Cretaceous sediments of the Atlantic Coastal Plain [Stadnichenko and others, 1953, p. 15]. Their minor-element content is similar in many respects, and their coalification has a genetic relationship. Data are given in tables.
The kettle-bottom coal is taken from partly coalified and sedimentfilled upright tree stumps found above the coal beds. These stumps generally fall out when the underlying coal is mined out. The shape of the cavity resulted in their being called kettle bottoms or cauldrons. The bottom of such stumps is in contact with the coal bed and the upper part is buried in sandstone or shale. The coalified trees are logs, branches, and leaf imprints of fallen trees lying horizontally and sometimes found as high as two feet above the coal bed. Only the main parts of large logs were collected but the designation "trees" was used during the collection to indicate that smaller units of the trees were present other than just the main trunk. These also are enclosed in shale or sandstone. In the coalified trees there is evidence of the compression and loss undergone by woody material after burial and during coalification. Several such tree trunks were very long [more than 20 feet], about 1 to 2 feet wide, but only 4 to 1 inch thick. The tree trunks had lenslike cross sections indicating that a round log during its coalification degenesis was reduced by about a 24:1 volume ratio. The specific gravity of these coals is about 1.2 to 1.3, and that of the living trees is about 0.5 to 0.7 This is only about a twofold increase in the specific gravity, indicating that only about 1 part in 12 remains of the original plant material. As a result of this, large quantities of humic and perhaps amino acids would be available
to react with metal ions or complexes passing through the degenerating logs to form metallo-organic complexes.
These kettle-bottom coals and coalified trees were not coalified in the same way as the trees that were laid down in the swamp, although their coal is probably of the same rank as the coal of the beds, and the degree of overall coalification was probably similar. Plant structures in these types of samples are usually much better preserved than in any of the coal bed samples. This indicates less degeneration of plant tissues in the kettle-bottom coals and trees than in trees coalified in the swamp environment. Degradation of the celluloses and proteins certainly took place to form humic acid, but the rate was probably much slower than under swamp conditions. These trees were enclosed by inorganic sedimentary material more rapidly than the organic debris of the coal swamp. As a result of this, bacterial action was reduced, and the pH was probably higher. The slower decomposition and the enclosed environment probably produced better conditions for the retention of the elements already in plant tissues and also for the greater absorption of and reaction with metallic ions or complexes in solutions passing through the buried logs. Their enclosure in clastic materials suggests that they were buried at a time when large amounts of clastic material and material in solution were being brought into the depositional basins.
The minor-element content of these samples has no direct relation to that of the coal beds. Table 13 gives the amount of the element in parts per million in coal of the kettle-bottom coals and coalified trees and of the associated beds. If more than one kettle-bottom coal was analyzed, the figures are the average. Table 14 presents the ratios of the elements in the kettle-bottom coals and coalified trees to those in the beds.
TABLE 13.- Comparison of the minor-element content of kettle-bottom coals [KB]
and coalified trees [Tr] with the associated coal beds
[In parts per million in coal]
1.8 3.8 17.1 118 551
1, 350 323 30.4 22.8 9.4 1.2 3. 8 2.3 5.4
10.3 0
0 60.8 7.7 20.0 5.9
4.8 1.8 26.6 5.6 11.6 24. 2 1.3 11.1
Cu. Zn. Ga.. Ge. Mo. Sn. Y La.
1.2 30.0 832 325 158 16.6 24. 1 9.2 0 18.3 37.4 4. 2 0 16.6 5.8
1.1 137 337 16.1 3.7 1.1 2.1 11.6 0 2.9
..5 2.1
3.0 35.0 96.6 142 53.3 3.8 7.7 4.6 0 19.2 84.8 1.2 2.2 31.4 3.6
8.2 21.0 288 17.1 14.3 3.0 2.8 13. 3 0 9. 3 6.5
3.9
6.2 846 250 84.9
6.3 15.4 9.6 0 12.5 184
4.4 2.0 26. 2 3. 9
1.1 167 197
9.3 4.7 1.7 3.4 8.7 0 4.1 1.5
75
5.8 42.8 151 35.4 12.6 10.1 10.1 12.6 0 6.6 5. 3
1.2 76.9 370 16.8 3.0 1.0 2.1 16.6 0 2.9 .10 .55 .55 5.3 12.4
TABLE 14.—Ratios of the minor-element content of the kettle-bottom coals and coali
fied trees to that in the associated beds
The approximate order of abundance for the elements in the kettlebottom coals and coalified trees in relation to the beds above which these samples were found is Ge>V>Cr>Ga>Co,Ni, Y>Mo,Be, Ti,Sn>Cu>La>B [tables 13 and 14]. The first four of these elements are very highly concentrated in the kettle-bottom coals and coalified trees as compared to the beds. The next seven are less concentrated in the kettle-bottom coals and coalfied trees as compared to the beds, whereas the last three elements are depleted in the kettlebottom coals and coalified trees. Thus boron, which is most highly concentrated in the beds, is the least concentrated in the special samples; chromium, which is least concentrated in the beds, is among the more abundant elements in the kettle-bottom coals and coalified trees. There is a similar reversal for vanadium and several other elements.
Except for vanadium, chromium, gallium, and germanium, the element content of the kettle-bottom coals and coalified trees is not higher than that in many plants. Germanium and gallium are not toxic to plants; so it is possible for plants to have large accumulations of these metals. Vanadium is known to be concentrated highly in the ash of some crude oils and in some organisms in the sea; like chromium, however, it is quite toxic to most plants. Some selective plant types can grow in chromium-rich soils, but kettle-bottom coals and coalified trees are not formed from these types of plants.
The element content of the vitrain samples, many of which are the remains of trees buried in the peat of the coal swamp, is similar to the blocks of coal from which they come. Two elements are an exception-the amount of germanium is usually much higher, and lanthanum is much lower in vitrain. The content of these two elements
in the vitrain particularly, bear a similarity to their content is kettlebottom coals and coalified trees. The coalification process that produced vitrain can be considered to be intermediate between the least and most intense processes of plant decomposition. This suggests that rate of degradation as well as the enviroment of deposition was responsible for the retention of elements already present in the plants or for the accumulation during and after burial.
The most probable method by which the amount of the minor elements now found in the kettle-bottom coals and coalified trees was controlled was the formation of metallo-organic complexes. The elements forming these complexes could be either those accumulated by the plant at the time of growth, or those acquired by the reaction of the elements carried in solution that passed through the degenerating plant tissues. To assess this means of acquisition of the minor elements, we examined several groups of elements for the stability of their organic complexes. Data for the provincial averages for the beds [table 6] show the ratio of yttrium to lanthanum to be almost 1:1. This is approximately the same as the ratio for all the beds listed in table 13, which is 1.2:1. The average contents of the kettle-bottom coals and coalified trees is yttrium, 25 ppm, and lanthanum, 3.8 ppm, or a ratio of about 6:1 to 7:1. It is obvious then that kettle-bottom coals and coalfied trees are enriched in yttrium and depleted in lanthanum as compared to the beds. Little can be said of the plant content of these elements as there is no way of knowing what the original content was, but it is known that parts of some plants can concentrate much larger quantities of these elements than are found in the kettle-bottom coals and coalified trees.
The stability constants of some yttrium and lanthanum organic complexes are as follows: Martell and Calvin [1952, p. 196] give the stability of rare earth chelates as yttrium greater than lanthanum. Vickery [1953, p. 84] lists Schwarzenbach's figures for the stability constants of lanthanon amino acid complexes; in the four cases listed, the stability constants of yttrium are much greater than lanthanum. The solubilities of these complexes are unknown; however it can be assumed that they are related to the stability constants, that is, the elements that form more stable metallo-organic complexes would also form more insoluble complexes.
The above relation suggests that the two elements were either introduced from solutions passing through the kettle-bottom coals or coalified trees and that yttrium, owing to the higher stability of its complexes, was selectively added to the kettle-bottom coals and coalified trees and that more lanthanum was selectively leached out from the original yttrium-lanthanum content accumulated during the growth of the trees. Without more knowledge about the content of
Page 3
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Portuguese]. Butler, J. R., 1953, Geochemical affinities of some coals from Svalbard [Spits
bergen]: Norsk Polarinst., Skr. no. 96, 26 p. Cannon, H. L., 1955, Geochemical relations of zinc-bearing peat to the Lockport
dolomite, Orleans County, New York: U.S. Geol. Survey Bull. 1000-D,
p. 109-185. Combo, J. X., Brown, D. M., Pulver, H. F., and Taylor, D. A., 1949, Coal re
sources of Montana: U.S. Geol. Survey Circ. 53, 28 p. Cooke, W. T., 1938, The occurrence of gallium and germanium in some local
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the ash of low-rank coal from Texas, Colorado, North Dakota, and South
Dakota: U.S. Geol. Survey Bull. 1036-H, p. 155–172. Dieke, G. H., and Crosswhite, H. M., 1943, The use of iron lines as intensity
standards: Optical Soc. America Jour., v. 33, p. 425-434. Dobbin, C. E., 1930, The Forsyth coal field, Ros Treasure, and Big Horn
Counties, Montana: U.S. Geol. Survey Bull. 812, pt. II-A, p. 1-55. Dono, Tsurumatsu, Yoshida, Takatoshi, Aoki, Minoru, Makagawa, Genkichi
and Iga, Motoichi, 1951, Geochemical investigation of lignite. II. Spectrochemical analysis of lignite: Nagoya Inst. Technol. Bull., v. 3, p. 199–20:
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and Bros., 624 p.
Page 4
Schleicher, J. A., and Hambleton, W. W., 1954, Spectrographic investigation of
germanium in Kansas coal: Kansas Geol. Survey Bull. 109, p. 113–124. Shakhov, F. N., and Efendi, M. E., 1946, The geochemistry of the coals of the
Kuznetsk basin: Acad. Sci. U.R.S.S. Comptes rendus, v. 51, p. 139–140 [in
English]. Simek, B. G., 1940, The germanium content of coals of the Ostrau-Karwin basin:
Chem. Listy, v. 34, p. 181-185 [from Chem. Abs., 1943, v. 37, p. 4036]. Simpson, A., 1954, The Nigerian coal field; the geology of parts of Onitsha, Owerri
, and Benue provinces: Nigeria Geol. Survey Bull. 24, 67 p. Stadnichenko, Taisia, Murata, K. J., and Axelrod, J. M., 1950, Germaniferous
lignite from District of Columbia and vicinity: Science, new ser., 112, p. 109. Stadnichenko, Taisia, Murata, K. J., Zubovic, Peter, and Hufschmidt, E. L., 1953,
Concentration of germanium in the ash of American coals, a progress report:
U.S. Geol. Survey Circ. 272, 34 p. Stadnichenko, Taisia, Zubovic, Peter, and Sheffey, Nola B., 1961, Beryllium
content of American coals: U.S. Geol. Survey Bull, 1084. [Stose, G. W. and Ljungstedt, 0. A.], 1932, Geologic map of the United States:
U.S. Geol. Survey. Stow, M. H., 1946, Dating sedimentation, vulcanism, and orogeny in Beartooth
Mountain region, Montana, by heavy minerals: Geol. Soc. American Bull.,
v. 57, no. 7, p. 675-686. Subrahmanyan, S., and Nair, A. P. M., 1955, Germanium in South Arcot lignite:
Jour. Sci. Indus. Research [India], v. 14B, p. 606 [from Chem. Abs., 1956,
v. 50, p. 6018]. Vickery, R. C., 1953, Chemistry of the lanthanons: New York, Academic Press,
Inc., 296 p. Vinogradov, A. P., 1956, The regularity of distribution of chemical elements in
the earth's crust: Akad. Nauk SSSR Geokhim., v. 1, p. 1–52. Translated by Botcharsky, S., 1957, Atomic Energy Research Establishment AERE
Lib/Trans-795, Harwell, England. Warren, H. V., and Delavault, R. E., 1954, Variations in the nickel content of
some Canadian trees: Royal Soc. Canada Trans., v. 48, ser. 3, sec. 4, p. 71-74. Warren, H. V., Delavault, R. E., and Irish, Ruth I., 1951, Further biogeochemical
data from the San Manuel copper deposit, Pinal County, Arizona: Geol. Soc.
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of the biogeochemistry of molybdenum: Royal Soc. Canada Trans., v. 47,
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gallium and germanium in ash of New Zealand coals: New Zealand Dept.
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Page 5
TABLE 1. Coal beds and samples collected, by States.
2. Location and description of the coal samples.--- 3. List of beneficiated block samples and composites... 4. Spectrochemical analyses of 15 minor elements in the ash of
coal from the Eastern Interior coal region----- 5. Average content of 15 minor elements in the ash of individual
coal-bed columns from the Eastern Interior coal region.---- 6. Average content of 15 minor elements in coal of individual
coal-bed columns from the Eastern Interior coal region..
7. Average content of 15 minor elements in coal and coal ash
from the Eastern Interior coal region.--- 8. Range of 15 minor elements in coal from the Eastern Interior
coal region.---- 9. Spectrochemical analyses of 15 minor elements in vitrain and
kettle-bottom coal.--
10. List of localities and coal beds with corresponding minor ele-
ment concentrations.--- 11. Comparison of the average abundance of 15 minor elements in
coal from the Eastern Interior coal region with other rocks.
Page 6
operating mines, almost twice as many samples were collected from these two beds as from all the others combined.
Table 2 gives the sample localities and the manner in which each locality was sampled.
1.-- Ill-D-7... Vermilion.... Two Rivers Coal Co., strip
mine near Danville, NE4 NE/4 sec. 17, T. 19 N., R.
11 W.
2..... Il-Ha-7.... do. Fairview Collieries Corp., Har- 7..
mattan strip mine, NEY4
SW44 sec. 3, T. 19 N., R. 12 W. 3. [ll-A-6. .... Henry.. Midland Electric Coal Corp.,
Mecca No. 1 strip mine, near
Atkinson. Ill-C-6..... Montgomery. Freeman Coal Mining Corp., 6.
Crown mine, 1 mile northeast
of Farmersville. 5A..... Il-F-6...... Fulton and Midland Electric Coal Corp., 6.
Knox.
Middle Grove No. 2 strip
mine, Farmington. 5B.... Il-R-5..... ..do. Midland Electric Coal Corp., 5.
Middle Grove No. 3 strip
mine, near Rapatee. 6.-.-.-- Ill-M-6.... Saline..... Peabody Coal Co., Majestic 6..
No. 14 mine, near Duquoin. 7A Ni-Ma-6... Marion.. Marion County Coal Mining 6.
Corp., Inc., Glenridge mine,
Centralia. 7B..... ni-Ma-5...
do...
Marion County Coal Mining 5...
Corp., Glenridge strip mine,
Centralia. 8. Ill-OB-b.... Franklin...-- Old Ben Coal Corp., Old Ben 6.
Page 7
TABLE 2.—Location and description of the coal samples-Continued
9.- III-Pa-... Christian... Peabody Coal Co., No. 17 mine,
7. 44 Pana, 10. M-Pw-6.... do. Peabody Coal Co., Pawnee No. 6.
8.04 10 mine, Pawnee. 11...... Ni-s-6...... Saline Sahara Coal Co., No. 6 mine, 6.
4.29 11 miles west of Harrisburg. 12A.... ni-TrB-6.../ Jackson... Truax Trser Coal Co., Burning 6.
7.03 Star mine, near Elkville. 12B... ni-TrB-5... do,
do.
5.
3. 04 13. Il-TrP-6.. Perry. Truax Traer Coal Co., Pyramid 6.
5. 68 strip mine, near Pinkneyville. 14.. I-V-6--- Vermilion.... V-Day Coal Co., V-Day mine, 6.
5. 58 near Danville, sec. 30, T. 19
N., R. 11 W. 15.----- -BB-.... Saline...... Blue Bird Coal Co., Blue Bird
3. 94 mine, 15 miles west of Harris
burg. 16. -B&W-5.. Gallatin...-B. and w. Coal Co., s mile 5.
5. 14 west of Junction. 17A... Il-E-&... Will Northern Illinois Coal Corp., 6.
3. 45 Essex strip mine, sec. 5, T. 31
N., R. 9 E. 17B...mi-E-2 do. Northern Mlinois Coal Corp., 2.
2. 60 Essex strip mine, near Braid
wood, sec 5, T.31 N., R. 9 E. 18... III-F-5.... Sangamon... Farrand Coal Co., near River- 5.
4.99 ton, sec. 12, T. 16 N., R. 4 W. 19... Il-G-..... Gallatin... Oak Hill Coal Co. mine, near 5.
5. 10 Gibsonia, sec. 24, T. 10 S.,
R.8 E., 3d principal meridian. 20.. 1-H-5.... Saline... Peabody Coal Co., No. 43 mine, 5.
4.93 Harco. 21. -8-5... --...do.... Sahara Coal Co., No. 7 mine, 13 5.
6.68 miles west of Harrisburg. 22 Il-Tr-5..... Fulton... Truax Traer Coal Co., Red Em- 5.
4.15 ber strip mine, near Fiatt. 23 I-W-5... - Sangamon... Wenneborg Coal Co. mine, near
5.
5.86 Sherman. 24. TU-B-2... Will and Wilmington Coal Mining Corp., 2.
2.95 Grundy. Braidwood strip mine, sec. 29,
T. 32 N., R. 9 E. 25... NI-A-1... Henry... Bugos-White Coal Co., Alpha 1.
4.92 mine, Alpha. 26. Il-P-1.. Fulton.. Putt Creek Coal Co. mine, 2
3.32 miles north of Cuba. HI-T-I.....Knox.... Knoxville Mining Co., Thermal 1....... 4.63
No. 1 mine, Knoxville. 28A... Ill-S-DeK.. Saline. Saxton Coal Corp., Saxton No. | De Koven. 3.13
2 strip mine, near Carrier Mills NEX sec. 20, T. 10 8.,
R. 5 E. 28B. 111-8-D8... do...
do..
Davis...
3. 18 29. Il-P-Mu... Jackson.. Phillips Coal Co., Phillips mine, Murphys. 7. 70
near Carbondale.
boro[?]. 30. TI-PH-LW. Gallatin..... Blue Blaze Coal Co., Blue Blaze Willis. 3. 42
mine, near Pounds Hollow Lake.
31. Ind-L-VII. Pike.
Landrey Mining Co., Inc., VII..
Landrey No. 1 strip mine, 6
miles northwest of Winslow. 32..---- Ind-s-VI..- Vermilion... Ayreshire Collieries Corp., Sun- VI.
spot strip mine, 5 miles south
west of Clinton, 33. Ind-D-VL.- Warrick... Ingle Coal Corp., Ditney Hill VI.
mine, 2 miles south of Elber
feld. Ind-P-V... do.. Shaw Mining Co., 244 miles V...
Page 8
compared with analytical curves constructed from synthetic stand- ards. However, because of interference, many of the boron and copper analyses were determined by visual comparison with the standard plates. A comparison of the spectrochemical and chemical determinations for molybdenum and germanium indicate a probable error for the spectrochemical determinations of about 30 percent. No check was made on the accuracy for the other elements, although the overall coefficient of variations for the mean of duplicate spectral
plates is +15 percent with a range of about 10 to 20 percent. The
lower limit of detection for each element is:
Limit of detec-
Limit of detection [percent] Element
tion [percent] B. 0.001 La..
0.003 Be.
.0001 Mo.
.0005 Cd.--
. 005 Ni.
. 0005 Co.. . 0005 Sn.
.001 Cr... . 0001 Ti..
. 005 Cu. . 0001 V.
.001 Ga. . 0005 Y-
.001 Gec. 001 Zn..
.01
The results of the spectrochemical analyses are listed in table 4, which lists the analyses of 15 elements in the ash of 475 block or composite samples, 12 vitrain samples, and 3 kettle-bottom coal samples. Cadmium is not listed because it was not found in any of the samples. Whenever an element is below the limit of detection, it is reported as a zero. The list includes data for 62 coal columnar samples. All the block samples from 24 of the columns were analyzed, whereas only part of the block samples from the other 38 columns were analyzed. The thickness of each block sample or composite sample is listed, including those which were not analyzed. The percentage of each bed that was analyzed is listed in table 2.
Page 9
TABLE 4.--Spectrochemical analyses of 15 minor elements in the ash of coal samples from the Eastern Interior coal region-Continued
46
28 2.77 .30
35 .30 1.87
35
TABLE 4.-Spectrochemical analyses of 15 minor elements in the ash of coal samples from the Eastern Interior coal region-Continued
05.34 6. 36 3. 50 3. 42 5. 30 5. 66 4. 69 11.74 13. 50
0.006 .008 .019 .019 .006 .006 .050
0.2
2 42 40 . 2 .2 1.2 .1 .2
01 011 013 009 01 020 03 04
0.03
02 026 .031 .04 .058 .09 .04 .08
.003 .002 .002 .003 .03 .005
0.02 .
02 . 084
10 044 .064 .079 .01 01
.002 .0065 .012 .02 .031 0723 020 02
007 02 .02 .018 024 020 021 072
003 006 0014 004 0042 002 002
016 027 009 .051 28 042 028 024 044 025 058
.0085 .0068 .012 .014 .008
TABLE 4.-Spectrochemical analyses of 16 minor elements in the ash of coal samples from the Eastern Interior coal region -Continued
Page 10
7. 20 9. 18 7. 37 14. 72 9. 10
.005
004 .0047 .0032 .005
19. 94 30.00 9. 08 1. 73 1. 87 1. 46 4. 36 4. 10 8. 88
019 006 001 02 078 .078 .02 022 022
0028 .002 .002
0095 . 031
035 .02 .020 014
.01 003 008 027 036 060 03
009 002 012 034 02 050 057
TABLE 4.-Spectrochemical analyses of 15 minor elements in the ash of coal samples from the Eastern Interior coal region--Continued
1. 2-51 6-81 9-131 14. KB-1. KB-2.
12. 10 2. 25 2.00 3. 45 17.72 4.94 2. 26
.3 1.0 2.2 1.2
.3
8. 5 >10
.01 .009 .013 .01 005 01 01
3-4. 5.. 6-7. 8. 9. 10-11
. 44 . 19 .79 .11 .37 .18 .27
22 .31 08
See footnotes at end of table.
TABLE 4.-Spectrochemical analyses of 15 minor elements in the ash of coal samples from the Eastern Interior coal region-Continued
Ky-Go-9.-11.
21 31 4-7. 8. 9. 10. 11-12 13. 14. 7v
.003 .003
0035 .0027 .003 .002 .002 .03
.04 .04 .024 .008 .005 .003
10. 40 11. 56 5. 22 3.07 5.08 5.41 7. 44 11.88 13. 56 14.62
.05 .05 .03* . 09" .02 .0.5" .02* .02* .003 .030
2.0 1.8 .016 .028
.01
01 .01 02 02 .018
.004
007 .002 .007 .007
.[02
.0005
.1 .046 002 .018 .02
004 .002 ,005 .002
.000 .002 0
.01 .00610
.005 .005 .004 .005 .007* .014
Page 11
When the coal samples were being prepared for grinding, several bands of vitrain, as much as 1 cm thick, and a bony parting were separated from the blocks in which they were contained. These
samples were analyzed separately, and the analyses are given in table .-9, along with the analyses of the enclosing of adjacent whole blocks
for comparison. Table 9 also gives the analyses of three samples of kettle-bottom coal and the adjacent block samples from the top of the bedded coal with which they were associated. The samples of vitrain and kettle-bottom coal have less ash than the adjacent blocks with which they are compared. The bony parting contains more ash than the adjacent block sample. These samples are useful, therefore, in providing evidence of those elements that are associated with the organic and mineral matter of coal.
When compared with the block samples, the germanium content is slightly higher in three of the four vitrain samples; beryllium, boron, titanium, vanadium, cobalt, and gallium contents are slightly higher in two. Nickel, copper, and yttrium contents are lower in three of the vitrain samples. Chromium, zinc, molybdenum, and lanthanum
. are considerably more concentrated in the coal block samples. The sample of a bony parting differs somewhat from the vitrain samples in that gallium and germanium are somewhat more concentrated in the parting than in the adjacent, more nearly pure coal.
The samples of kettle-bottom coal contain unusually high concentrations of vanadium, chromium, nickel, copper, and yttrium. Kettlebottom coal samples from the northern Great Plains province were previously found to have similar concentrations of minor elements [Zubovic and others, 1961a, p. A46-A52]. The germanium concentration, however, which is especially high in kettle bottoms from the northern Great Plains, is low in kettle bottoms from the Eastern
Interior region. Titanium is a major constituent in two of the samples ś of kettle-bottom coal but is a relatively minor one in the third.
Because beryllium, boron, gallium, and germanium are known to be associated predominantly with the organic matter in coal [Zubovic and others, 1961b], we thought they might be concentrated in the kettle-bottom coal samples, but the analyses indicate they are more concentrated in the adjacent coal blocks.
VERTICAL DISTRIBUTION OF MINOR ELEMENTS IN
SELECTED COAL BEDS
The distribution profiles of the minor-element contents were plotted in the form of bar diagrams on plate 1 for selected coal beds from eight
Page 12
bal from Illinois and its correlative from Kentucky show a similarity i the profiles for different elements only in the sample from Kentucky. n the profile for the sample from locality 51 in Kentucky, only eryllium, tin and yttrium have distribution profiles that differ from ther elements. The distribution profile of the sample from locality 3 from the southern part of the region, like the others from Kentucky, hows a large degree of similarity in the distribution of most of the lements except for beryllium, tin, and yttrium. In general, most of he distribution profiles for localities in northern Illinois and Indiana re irregular and show no similarity in the pattern for different elenents in the same bed, whereas the profiles from localities in Kentucky ind some from southern Illinois show some degree of regularity for lifferent elements in the same profile.
Many of the distribution profiles indicate a tendency for some of the elements to be concentrated at the top and bottom of coal beds. Likewise, there is a tendency for total ash to increase toward the top and bottom of the coal beds. Both relationships probably reflect
. the greater availability of mineral matter and mineral-rich solutions toward the beginning and end of the interval of accumulation of the plant debris that eventually becomes coal.
We believe that the position of a coal bed relative to the margin or center of the basin of deposition may be a factor in the regularity or lack of regularity in the distribution profile of the different minor elements. Coal near the margin of the basin of deposition may have a heterogeneous vertical distribution of the elements because of the variable conditions of weathering and erosion in the borderland. The environment in the interior of the coal basin is more uniform, and this uniformity is reflected in the similarity of the distribution profiles for different elements. Presumably, northern Illinois was near the margin, and southern Illinois and Kentucky were near the center of the original basin of deposition.
AREAL DISTRIBUTION OF THE MINOR ELEMENTS IN
COAL BEDS
In the following discussion of areal distribution, emphasis is placed on the average minor-element content of coal at the 47 more representative localities. The localities of the samples in which each of the 15 minor elements are most concentrated are noted below and in table 10. However, because of insufficient sample density, the areal distribution for individual beds is not evaluated.
Page 13
TABLE 10.—List of localities and coal beds with corresponding
minor element concentrations
Individual coal beds containing from 5.1 to 7.6 ppm [parts per million] beryllium occur at localities 28B, 31, 37, and 40, scattered throughout the eastern and southern parts of the region. The ash of these beds contains from 0.009 to 0.018 percent beryllium. An earlier paper [Stadnichenko and others, 1961] discussed the possible source of the beryllium and compared the beryllium content of this region with other regions that were also sampled.
Concentrations of boron in coal ranging from 149 to 228 ppm were found at localities 1, 3, 4, 9, 17A, 17B, 27, 35, 41, and 47B. The samples from these localities show that boron has a more uniform distribution throughout the region than any other element. Individual beds contain as much as 0.5 percent boron in the ash.
TITANIUM As much as 1,000 ppm titanium occurs in individual beds of coal at localities 39, 40, and 47A in the eastern and southern part of the
region. A concentration of more than 1 percent titanium occurs in the ash of coal beds from a number of other localities, especially : in the southeastern part of the region.
Unusually high concentrations of vanadium occur in coal bed 9 at localities 46 and 51 in Kentucky; here the averages for the bed are 222 and 182 ppm in the coal, respectively. The greatest enrichment occurs at the top of the bed; for example, the upper sample block at locality 46 contains nearly 0.5 percent vanadium in the ash. The same bed also shows an enrichment of vanadium at the top of the bed at localities 7A, 16, 52, and 49 in the southern part of the region.
CHROMIUM
Coal beds containing more than 45 ppm chromium occur at localities 46, 47A, and 51. The highest concentration is at locality 51, with 53.5 ppm chromium in the coal and 0.054 percent in the ash.
Coal beds that contain from 10 to 20 ppm cobalt occur at localities 17B, 27, 37, 39, and 42A, widely scattered throughout the region. The ash of these beds contains from about 0.01 to 0.024 percent cobalt.
NICKEL
Coal beds containing more than 30 ppm nickel occur at localities 17B, 31, 37, and 46. At locality 17B, in northern Illinois, the No. 2 coal contains 46 ppm nickel in the coal and 0.1 percent nickel in the ash; the other localities are in Indiana and Kentucky.
Coal beds containing about 20 ppm copper or more occur at localities 9, 17B, 21, 24, and 39. At locality 9, in central Illinois, the No. 6 coal contains 41 ppm copper in the coal and 0.05 percent copper in the ash. The next highest average copper content is at locality 24, where the No. 2 coal bed contains less than 25 ppm copper.
The highest concentrations of zinc in coal occur at localities 3, 9, and 17A, where the beds contain 597, 268, and 415 ppm zinc respectively. The coal at locality 3 contains 0.78 percent zinc in the ash, about one-tenth the amount contained in an individual block sample from the same locality, which also includes a number of blocks in which zinc is reported to be below the limit of detection. GALLIUM The unnamed coal bed at locality 40 in Indiana contains 17.6 ppm gallium in the coal and 0.025 percent gallium in the ash. The best highest concentration is at locality 48, where the coal contains 11.3 ppm gallium. Samples from all other localities contain less than 10 ppm gallium.
GERMANIUM A concentration of as much as 30 ppm germanium in coal beds occurs only at localities 9, 40, and 47B. The ash of these beds ranges from 0.029 to 0.058 percent germanium. Elsewhere a number of beds contain concentrations of germanium in only the upper or lower block samples, which may have as much as 0.1 percent germanium in the ash.
MOLYBDENUM Concentrations of more than 10 ppm molybdenum occur at localities 40, 44A, 44B, and 51. The highest concentration is in the No. 11 coal bed at locality 44A, which contains 18 ppm molybdenum in the coal and 0.033 percent molybdenum in the ash. Other localities contain as much as 0.1 percent molybdenum in the ash of individual block samples, especially near the top and bottom of the beds.
Kentucky localities 41, 48, and 51 contain the highest concentrations of tin, 21.9, 4.5, and 5 ppm tin, respectively. The ash of these same beds contains 0.014, 0.02, and 0.0093 percent tin, respectively.
Coal beds with an average of 10 ppm yttrium, or more, occur at localities 9, 28A, 28B, 32, 38, 39, 40, 41, 42A, and 48, of which all but locality 9 are in the southern or eastern part of the region. Locality 40 has the highest concentration: 32.9 ppm in the coal and 0.046 percent in the ash.
LANTHANUM
Samples from localities 27, 28B, 39, and 47B, from widely scattered parts of the region, all contain as much as 10 ppm lanthanum in the coal. The highest concentration is at locality 39, which has 36.2 ppm lanthanum in the coal and 0.036 percent in the ash.
ABUNDANCE OF MINOR ELEMENTS IN COAL FROM THE EASTERN INTERIOR COAL REGION
COMPARED WITH OTHER ROCKS
A comparison of the abundance of 15 minor elements in coal from the Eastern Interior coal region with other coal and other rocks is
seful in evaluating the significance of the data. For this purpose,
ne compared the average-abundance data with similar data previusly reported from the coal beds of the Northern Great Plains coal
rovince [Zubovic and others, 1961a, p. A31] and with data for other ocks compiled by Turekian and Wedepohl [1961], as shown in able 11. Germanium, molybdenum, chromium, vanadium, and
CABLE 11.—Comparison of the average abundance of 15 minor elements in coal from
the Eastern Interior coal region with other rocks
nickel are more than twice as abundant in coal from the Eastern Interior coal region as in coal from the Northern Great Plains coal province. Of these, germanium and molybdenum are both more abundant in coal from the Eastern Interior coal region than in shale or the common igneous rocks. Germanium especially appears to be concentrated to a significant degree in the coal, being about 10 times more abundant than in igneous rocks.
MODE OF ORIGIN OF MINOR ELEMENTS IN COAL Many investigators have studied the occurrence of rare and minor elements in the ash of coal, and many references to the literature are cited in the summary report by Gibson and Selvig [1944]. Most of the investigators have commented on the probable mode of origin of various elements, especially the elements that occur in unusually high concentration. Three principal methods of concentration were proposed by Goldschmidt [1950, p. 240], who was one of the pioneers of this work: [1] concentration during the life of the plants, [2] concentration during decay of the organic substances, and [3] concentration by reaction with aqueous solutions after burial under younger
sediment. Others have elaborated on these ideas and suggested specific ways of concentration for specific elements. For example, Headlee and Hunter [1951, p. 11-12] suggested that the unusually high concentrations of germanium in certain coal beds probably resulted from introduction after burial.
Our observations on the distribution of minor elements in coal support in general most of the ideas expressed by other investigators. We believe that a certain amount of the elements present in the organic matter of coal were accumulated during growth of the plants. This method was the predominant means of accumulation during the initial phases of the formation of the swamp when plants had their roots in the subsoil. Part of the minor-element content of a large portion of the subsoil could have thus been concentrated in the bottom layers of the coal beds, and the large amounts of the elements generally found in these coal-bed layers could be thus explained.
During the main sequence of organic-matter deposition, the elements brought in solution into the swamps from the borderland probably combine with the decaying organic matter in the swamp to form complexes that are the principal means of accumulation of the elements. The large amounts of some of the elements found at the top of coal beds can be attributed to postburial formation of complexes of the elements with the underlying organic matter. The source of the elements can be either the overlying strata or the eroding borderland. If the borderland was the source the elements could have been carried easily by percolating solutions through the overlying unconsolidated strata into the coal bed.
Accumulation of elements in the major portion of the coal beds excluding the enriched top parts is probably syngenetic with the accumulation of the organic matter.
Averitt, Paul, 1942, Coal fields of the United States: U.S. Geol. Survey map,
scale 1:2,500,000. Cady, G. H., 1952, Minable coal reserves of Illinois: Illinois Geol. Survey Bull. 78,
Cohee, G. V., chm., 1962, Tectonic map of the United States exclusive of Alaska
and Hawaii: U.S. Geol. Survey and Am. Assoc. Petroleum Geologists,
scale 1:2,500,000. Gibson, F. H., and Selvig, W. A., 1944, Rare and uncommon chemical elements
in coal: U.S. Bur. Mines Tech. Paper 669, 23 p. Goldschmidt, V. M., 1950, The occurrence of rare elements in coal ashes: Prog
ress in Coal Science, p. 238–247. Headlee, A. J. W., and Hunter, R. G., 1951, Germanium in coals of West Virginia:
West Virginia Geol. Survey Rept. Inv., no. 8, 15 p. McFarlan, A. C., 1943, Geology of Kentucky: Lexington, Kentucky Univ.
Press, 531 p.
Page 14
pencer, F. D., 1953, Coai resources of Indiana: U.S. Geol. Survey Circ. 266, 42 p. adnichenko, Taisia, Murata, K. J., Zubovic, Peter, and Hufschmidt, E. L.,
1953, Concentration of germanium in the ash of American coals—a progress
report: U.S. Geol. Survey Circ. 272, 34 p. tadnichenko, Taisia, Zubovic, Peter, and Sheffey, N. B., 1961, Beryllium content
of American coals: U.S. Geol. Survey Bull. 1084-K, p. 253–295. urekian, K. K., and Wedepohl, K. H., 1961, Distribution of the elements in
some major units of the Earth's crust: Geol. Soc. America Bull., v. 72, p.
175–192. J.S. Bureau of Mines, 1959, Bituminous coal and lignite in 1958: Mineral Market
Summary 2974, Sept. 9. 1959. Wanless, H. R., 1955, Pennsylvanian rocks of Eastern Interior basin: Am. Assoc.
Petroleum Geologists Bull., v. 39, p. 1753-1820.
1956, Classification of the Pennsylvanian rocks of Illinois as of 1956: Illinois
Geol. Survey Circ. 217, 14 p. Wanless, H. R., and Weller, J. M., 1932, Correlation and extent of Pennsylvanian
cyclothems: Geol. Soc. America Bull., v. 43, p. 1003–1016. Weller, J. M., 1930, Cyclical sedimentation of the Pennsylvanian period and its
significance: Jour. Geology, v. 38, p. 97-135. Zubovic, Peter, Stadnichenko, Taisia, and Sheffey, N. B., 1961a, Geochemistry
of minor elements in coals of the Northern Great Plains coal province: U.S. Geol. Survey Bull. 1117-A, P. Al-A58.
1961b, Chemical basis of minor-element associations in coal and other carbonaceous sediments: Art. 411 in U.S. Geol. Survey Prof. Paper 424-D, p. D345-D348.
Page 15
UNITED STATES DEPARTMENT OF THE INTERIOR
STEWART L. UDALL, Secretary
William T. Pecora, Director
For sale by the Superintendent of Documents, U.S. Government Printing Onice
Washington, D.C. 20402 - Price 20 cents [paper cover]
Abstract Introduction Acknowledgments.- Stratigraphy.. Sampling and sample preparation Methods of analysis. Analytical data- Evaluation and summary of the data -- Distribution of elements among coal components.----
Comparison of float fractions and whole coal samples. - Comparison of vitrains, fusains, and kettle-bottom coal with blocks of
whole coal.----
Comparison of blocks of coal with included pyrite.. Comparison of coal samples from the three principal areas of the Appalach-
ian region.---- Comparison of coals from various regions of the United States. Summary and conclusions.. References.
Pago C1
1 2 2 3 15 16 16 16 16
Figure 1.—Map showing distribution of coal samples in the Appalachian
region.-
TABLE 1. Location and description of the coal samples.
2. Data on flotation of samples --- 3. Spectrochemical analyses of the ash of coal samples of the
Appalachian region.--.
4. Average minor-element content of the ash of the columnar
samples of coal..--.
5. Average minor-element content of the columnar samples of
coal.--
6. Average minor-element content of the floated and whole coals.
7. Average minor-element content of the columnar coal samples
and ash fractions.... 8. Analyses of fusains, vitrains, and blocks of whole coal.. 9. Analyses of coal samples and included pyrite....
10. Average minor-element contents of coal from 3 areas of the
Appalachian region...
11. Average minor-element contents of coals from various regions
of the United States.
MINOR ELEMENTS IN AMERICAN COALS
DISTRIBUTION OF MINOR ELEMENTS IN COALS OF THE
APPALACHIAN REGION
By PETER ZUBOVIC, TAISIA STADNICHENKO, and NOLA B. SHEFFEY
Spectrochemical analyses were made for beryllium, boron, titanium, vanadium, chromium, cobalt, nickel, copper, zinc, gallium, germanium, molybdenum, tin, yttrium, and lanthanum in 73 columnar samples of coal beds of the Appalachian region. The analyses indicate that coals of the northern area, Ohio, Pennsylvania, and Maryland, contain larger quantities of boron, titanium, chromium, nickel, zinc, gallium, germanium, and yttrium than the central or southern areas. The coals of the central area, Kentucky and northern Tennessee, contain the largest amounts of beryllium, tin, and lanthanum. The coals of the southern area, Alabama, Georgia, and southern Tennessee, are highest in vanadium, cobalt, copper, and molybdenum. No definite reason for the differences can be ascribed; however, the fact that these coals vary considerably in stratigraphic position may be a factor. Another factor may be differences in source rocks, as the samples cover a large geographic area.
Analyses of 12 samples of pyrite taken from the coals do not indicate any rela. tion between the minor-element content of the pyrite and coal.
Investigation of vitrain and fusain fractions supports, in general, an organicaffinity series of the elements established in earlier work. Coals of the Appalachian region contain much less zinc, boron, and tin than do those of the Northern Great Plains coal province or the Eastern Interior coal region.
Coals of Pennsylvanian age in the Appalachian region of the eastern United States have been an important factor in the economic development of the country and are well known. Aside from their use as an energy source, they have come to be important to the chemical industry, and are known, from previous geochemical studies, to contain high concentrations of some of the minor elements [Headlee and Hunter, 1955; Stadnichenko and others, 1953; Zubovic and others, 1961a].
The distribution of these elements in several important coal beds of Pennsylvanian age that occur over broad parts of the Appalachian region is the subject of this report. Investigation was also made of the distribution of the elements among various organic and inorganic components. The elements of interest are beryllium, boron, titanium, vanadium, chromium, cobalt, nickel, copper, zinc, gallium, germanium, molybdenum, tin, yttrium, and lanthanum. It is doubtful whether the concentrations of any of these elements in the coals can be regarded as economically important at present. This study, however, has been of reconnaissance nature and intended only to search for broad areas that may be of interest in further investigations.
The authors wish to thank the mine operators and the miners who generously gave their time and the use of their equipment, thus easing the many problems of sampling the coals in the mines. Thanks are also due the personnel of the State Geological Surveys of Ohio, Kentucky, and Alabama for their help in acquainting the authors with the coals of their States. J. W. Huddle, of the U.S. Geological Survey, and his coworkers were particularly helpful in sampling the coals of eastern Kentucky and Tennessee.
In the preparation of the samples, the assistance of J. H. Townsend and H. M. Cohen proved to be invaluable. Elizabeth L. Hufschmidt and H. J. Rose, Jr., made some spectrographic analyses of the coal ash before Nola B. Sheffey became associated with the project as a full-time spectrographer.
Many other members of the U.S. Geological Survey extended their help in the interpretation of the geochemical data and in the preparation of this report.
STRATIGRAPHY
In the northern part of the Appalachian region the rocks of Pennsylvanian age are divided into four formations which have been named, from oldest to youngest, Pottsville, Allegheny, Conemaugh, and Monongahela. All four of the formations are present in parts of Pennsylvania, Ohio, and West Virginia; rocks of Allegheny age or younger are absent south of Kentucky, and those of Nonongahela age do not occur south of West Virginia.
In Kentucky, the rocks of Pottsville age are divided into two units: the lower is the Lee Formation and the upper is the Breathitt Formation [Wanless, 1946, p. 10, 63–64; McFarlan, 1943]. The Breathitt is equivalent to the Briceville, Jellico of Glenn [1925], Scott, and Anderson Formations in Tennessee, and the Kanawha Formation of southwestern West Virginia. The Pottsville equivalents in southern Tennessee and Georgia are described by Wanless [1946]. The many equivalents of the Pottsville rocks in Alabama are discussed by Adams and others [1926, p. 208–230]. In addition, coals of the Warrior Basin of Alabama are described by McCalley [1900], those of Georgia
Page 16
TABLE 1.- Location and description of the coal samples
[Leaders indicate no measurement made]
Coal bed and geologic
formation
Num- Percent ber of
of bed blocks analyzed
Columbiana - J. and R. Coal Co. mine,
near Guilford Lake,
Lisbon. Carroll Stark Ceramics Co. mine, on
Cameron farm, near
Malvern. Coshocton. Abandoned mine, on Harris
farm, near Sunnybrook. Stark
Stark Ceramics Co., pit 14,
East Canton. Perry
Sunnyhill Coal Co., Sunny
hill No. 8 mine, New
Lexington. Jackson. Exposure, near R. and W.
Coal Co. mine, about 2 miles east-northeast of
Wellston, on route 349. Stark
Billman Coal Co. mine, on
Miller farm, near Waynes
burg. do
Magnolia Mining Co., Mag
nolia mine, on McCall
farm, near Waynesburg. Carroll Stark Ceramics Co. mine, on
Cameron farm, near Malvern.
Page 17
Table 1.- Location and description of the coal samples-Continued
Rochester & Pittsburgh Coal Dean [Breath- Co. mine, Briceville.
itt Forma
tion]. New Jellico Coal Co., Inc., Jellico [Breath- Blue Rose mine, Morley. itt Forma-
tion]. Dippel & Dippel Coal Co. Jellico [Mason] mine, Clairfield.
[Breathitt
Formation]. Blue Diamond Coal Co., Jellico [Breath- Eagan mine, Eagan.
itt Forma
tion]. Block Coal & Coke Corp., Kent [Coal Anthras mine, Vasper.
Creek] [Breathitt
Formation]. Tennessee Products & Chemi- Sewannee [Lee cal Corp., Reel's Cove
Formation]. mine, Whitwell. Tennesssee Consolidated
--do Coal Co., Palmer mine, Palmer.
Table 1.—Location and description of the coal samples-Continued
Nickel Plato
[Pottsville l'ormation].
In the laboratory, the blocks were either broken or cut in half; one-half was rewrapped and put into storage. The other half was broken into pieces small enough that the visible noncoaly matter, such as lenses or fracture fillings of pyrite, calcite, or shale, could be removed from the sample. Twelve samples of pyrite were analyzed for minor elements. In the latter stages of the project, many of the high-ash coals were floated to remove mineral matter.
The samples were crushed to pass through a 100-mesh sieve. Ten grams of this – 100-mesh coal from each of the block samples were placed in a cold muffle furnace. The temperature was then gradually raised to 450°C and held there until all the organic matter was oxidized. Ash derived from coal at this temperature may differ somewhat from that derived from combustion at higher temperatures. At higher temperatures larger amounts of volatile inorganic constituents may be lost.
In the flotation process a – 100-mesh-size fraction was centrifuged in ethyl alcohol and carbon tetrachloride [specific gravity ranging from 1.32 to 1.36], for 20 minutes. The float fraction was decanted into a Büchner funnel, dried, ashed, and analyzed spectrographically. The percentages of float material recovered and the ash contents of the material are given in table 2.
The lighter fractions of the coal separated by the flotation process are of interest for two reasons: [1] a large part of their minor-element content is chemically bound to organic constituents rather than mineral matter, and [2] the lighter fraction is roughly comparable to coals cleaned by mechanical means before shipping [Averitt, 1961, p. 25], and hence, more comparable to coal from which commercial separation of minor elements might be attempted. Horton and Aubrey [1950] found that germanium and other elements tend to be associated with lighter float fractions.
TABLE 2.-Data on flotation of samples
[Location of samples shown in table 1]
Ash [percent of float traction]
Page 18
Blocks of coal were selected for spectrographic analysis on the basis of preliminary determinations of germanium and molybdenum. Blocks having low concentrations of these elements, particularly germanium, were combined into composite samples, and many of these were floated because of their high ash content. The preliminary germanium and molybdenum determinations were made by rapid methods [Zubovic and others, 1961a]. The final germanium and molybdenum determinations, as well as the determinations for 13 other elements, were done by a quantitative spectrographic procedure.
The quantitative spectrographic procedure used has been described by Zubovic and others [1961a, p. 18-20]; therefore, only a brief outline of the method is given here.
The total energy method, employing d-c arc excitation of samples and synthetic standard, was used. The spectra of samples and standards are recorded on photographic plates that cover the wavelength region 2300-4700 A with a dispersion of 5 A per millimeter. The transmittances of the analytical lines were measured with a microphotometer, and the photographic plates were calibrated by using a set of homologous iron lines for which relative intensities are known [Dieke and Crosswhite, 1943]. By the use of synthetic
[ standards, analytical curves were constructed which relate the logarithm of intensity of analytical lines to the logarithm of concentration. Concentrations of the various elements were determined from these curves.
The spectral lines used and the corresponding detection limits are listed below:
The final analytical results are, in general, averages of two determinations made on separate plates. The overall coefficient of variation for the mean of such duplicates for all the elements is $15 percent.
ANALYTICAL DATA The minor-element content of the ash of each of the individual and composite block samples comprising the 73 columnar coal samples is given in table 3.
Table 4 shows the average minor-element content of ash in weight percent for each of the columnar samples. Table 5 shows the average content of the elements on the basis of parts per million in coal for each of the columnar samples. The averages for columnar samples in which more than 75 percent of the bed was analyzed were computed on a weighted basis using the thickness of the analyzed blocks making up the columnar sample. The other averages are unweighted.
EVALUATION AND SUMMARY OF THE DATA
The analytical data in table 3 and the columnar-sample averages in tables 4 and 5 may not be representative of the minor-element content of the sampled beds. This study was reconnaissance in nature and in most places too few samples were obtained from any one bed. However, this study does provide a groundwork for further geochemical investigations that may be undertaken.
In the computation of some averages given in this report, analyses of float fractions of the coals were used along with analyses of coals not separated in this manner. Where this was done, the resulting averages for particular elements are somewhat different from those that would have been obtained if the float fractions were not included. However, the averages given in table 6 for floated and unfloated samples from the same general areas demonstrate that the effects of this procedure are not great for most elements.
The estimated average minor-element contents of coals of the Appalachian region and their ash fractions are given in table 7. These figures were derived from the averages for the columnar samples given in tables 4 and 5.
DISTRIBUTION OF ELEMENTS AMONG COAL
COMPONENTS
COMPARISON OF FLOAT FRACTIONS AND WHOLE COAL SAMPLES
Average minor-element contents of coals, with averages for float fractions of coals from the same areas, have been given in table 6. The elements found to be more highly concentrated in the float frac
Table 3.--Spectrochemical analyses of the ush of coal samples of the Appalachian region [Figures indicate percent by weight: visual estimate; 0, below limit of detection; leaders indicate no analysis made; 1, floated sample; F, fusain; V, vitrain; a, b, c, subdivision
of a block collected as a unit. Location of samples shown in table 1]
.008
01 .01 .02 003 004 003
.003 .007 .006 .005 002 003
2. 70 1. 50 6.00 6. 94 10. 22
5. 66 17. 50 4. 68 6.54 6.72
.02 02 02 009 004 04 01 02 02 01
25 30 60 40 16 30 84 06 . 12
Page 19
TABLE 3.-Spectrochemical analyses of the ash of coal samples of the Appalachian region-Continued
9 10 11 12 13 14 15 16 17 1 2
3 4-10 11 1 2 3 4
9.98 7. 66 4. 44 8. 32 11. 50 20. 54 20. 30 11. 84
005 002
002 0 0
0014 .003
003 003 002 003 034 02 04
002 .003
002 003 022 01 03
.01 .003
003 .0007 .003 .002 .0003
03 004 002 001 001 003 002
02 009 005 003 004 004 0005
054 5 04 002 03 004 003 02 01 01 05
003 .008 . 02 .04 .02 01 01 01 01 06
27.88 26. 14 3. 56 3. 00 3.31 4. 50 3. 14
31. 14 8. 03 4.34 11.02 19. 74 29. 24 17.10 14, 12 13. 14 7. 78 4. 48 19. 98 10.06 9. 38 3. 00 4. 50 5. 67 7.54 7. 20 6. 66 3. 74 5. 08 12. 04 15. 14 12.00
0
003 004 021 03 . 02 03 02 .02
003 007 .003 002 C03 003 003 .003 002 005 006 . 027 .001 .002
003 .002 .007 . 082 .002 .002
005 .01 .005 .004 .003
003 005 .0025 .001 .001 002 002 .005 .001 .003 .003 004 007 002 .001 .001
003 02 .02 .015 01 02 03 02 05 02 02 02 05 04 01 .009 . 02
.02
08 .04 .08 .002 .02 .02 .05
43 15
55
03 85 27 30 45 16 14 16 22 35 .55
.02 .038 .03 .004 02 03 01 01
1 .002 01 01 09 08 04 . 02 .009
See footnotes at end of table.
TABLE 3.-Spectrochemical analyses of the ash of coal samples of the Appalachian region -Continued
0.82 .85 40 52 21 53 . 13 13
2. 06 4. 94 4. 26 2. 96 3. 80
. 12 72 30
99 2. 09 2. 42 1. 57
. 001 004 002 005 003 002 006 .02 .01
. 4 1.6
4 2 1.5 1 1.8 1.6
01 03 01 023 .01 014 045 045
9-121
13 14-181 19-231 24-311 33-351 36 371
1 2 3
. 02* 2* 02* 1* . 39
2* .1 2* 05 03 04
0
002 0
002
002 0
003 024
029 007 026 018 012 021 053 009 01
.01 038 02 045 .026 .012 .034
012 .03
04 . 02
03 007 03 04 02 03 02 03 02 02
006 007 01 007 01 006 005 004 003
. 15 .01 02 02 02 .02 .02 03 02 02 .02 03 03
5. 02 2. 29 4. 86 2.94 2. 47 1.85 2. 43 3. OR 1.92 2. 70 2. 50 2. 16 3. 20 4. 38 12. 92 18.68 6.32 9.92 6.82 5. 28 6.22 13.04 19.38 3.14 3.52 4. 56 2. 28 2.12 2. 62 5.44 0.00 5. 38 10. 92 3. 74
.009 01 01 02 02 02 02 02 02 02 02 02 .02 02 01 046 02 02
.005 .003
002 . 002 002 002 002 002
07 03 03 05 03 03 03 03 03 03 03 03 02 01 01 04 03*
.01 005 002 005 005 004 005 005 004 .01
00003 00002 0001 00003 00004 00003 0001 0001 005 004 0009 002 001
.02 .02 .01 02 01 01 01 .01 .01 007 01 02 02 02
.04 .04 .02 .01 .02 .02 .03 04 03 02 006 . 03 .3* .05* 3 05 .05* . 02 ,01* 03
.01 .02 0.51
03 03 03 .01
25 . 45
42 . 25 37 15 .31 . 37 .32
025 02 006 02 02 01 005 004 .003
004 .000
0006 0004 00012 002 0002 000
Ky-BD-Le...
1
25 2-41 1.35
5-71 2. 21 Ky-Pu-Hi.
1
. 39 2-3 1. 21 4
41
1. 58 Ky-Al-H..
1
34 2-31 40 4-71 98 8-10 74 9
36 11 21
121 12 Ky-Col-H.
la
63 1b . 10 lc 15
.18 29 32 23
33 Ky-Colz-H...
la 24 1b 38 1c 38 2
18 3-4 79
5-6f Ky-Sx-HA..
la .31 2-5 2. 12
18
88 10
41 11
27 12
20 13
38 Ky-SL-Wh.
1
18 2-31 4-6f 66 7-10 1. 41
11-131 98 Ky-PC-Am.
1
40 2-3f 4-61 94 7-9f
1. 16 10-111
.81 Ky-EJ-E..
1
. 55 2a-5 1. 73 2b .27
12 7-111 1. 17
.42
12-141 . 94 See footnotes at end of table.
Table 3.--Spectrochemical analy'ses of the ash of cool samples of the Appalachian region-Continued
1.23 0.008 1. 43 0004 3. 78 0005
8cf
1 2-5 ба
7 lar lb 2
3 4-5 la lb 2
3
1.11 17. 40 3. 00 1. 24 1.81 1.88 3. 68 13. 26 1.18
1.09 1. 66
21 .31
51 .38 18
41 1. 71
41 28 38 53 58
38 1. 05
23 58 78 54 30 50 38 86 70 41 70 80 37 32 .53 75 62
.035
02 .004 , Ꭴ22 C3 03 02 02 02 03 03 04 02 02 01
.07
02 .02 .064 .0.38 . 14 03 03 02 03 .03 06 03 03 03 03 .04 04 03
.018 .01
003 . 032 .023 .036 .02 007 04 . 06 .08 .08
02 , Ꭴ2 02 02 02 .03 . 03
01 005 022
027
10 03 01 02 08 .11 04 02 03 .02 .02
04 .04
.022 02* 02* 04
2*
2* .301 03 04 08 04 1 .1
006 . 004
0
004 006 005 004 002 003 005 004 005 007 006
1. 88 5. 56 3. 86 2. 14 2. 66 4. 06 1.86 2. 06
0
007 0 003 004 003 .002 003 003 .002
02 .002 0004 .0002 .0002 .0003 .0007
034 02 007 005 004 008 004 003
Page 20
ld
5
1 2-4
5
6 7-11 12
1 2-4
5 6-8
9 10a 10b 10c
6 7 8 9 1
2 3-5
6
ននន ន ន ន ន នង្គនន នននន នន្នខុន ន ន ទួន នន
4. 36 31. 22 10. 78 3. 38
. 44
14 .33
13 . 16 1. SO
25 3. 50
27 21 . 42 3.0
.64 1. 67 . 35
2. 84 2. 14 2. 74 3. 42 4. 92
.004 .0015
0015 .004 .006
See footnotes at end of table.
Table 3.-Spectrochemical analyses of the ash of coal samples of the Appalachian region-Continued
5 1-3
4 5-8
9 10a 10b
1
2 3-5
6 7-9
3. 74 5. 28 13. 88 1. 98 6. 28
. 32 . 19 1.03 .60 .77 . 26 .42 . 56 .71 27
4. 25 3. 54 4. 02 5. 70 9. 40 4. 97
. 013 017 007 . 007 .012 , Ꭴ23
009 0006 .015 .02 .012 .004
2 3-41 561
7 8
9 Raf
1
2 3-4 6-6
7 1
TABLE 3.-Spectrochemical analyses of the ash of coal samples of the Appalachian region-Continued
4 5-6
7
8 1-5
6 7-9
10 1-2
3 4-7
8 1
8 9-10
11 12 13 14 15 1-8
12 13
1 2-10
31 20
23 4.63
28 38 . 33
18 . 10 1.93
TABLE 4.-- Average minor-element content of the ash of the columnar samples of coal 10, below limit of detection; leaders indicate no data for element; *, not used in computing regional averages. Locations of samples shown in table 1]
0.0056
0088 0073 0019 0025 036
0095 0078 .0013
031 .0073
022 . 056 026
002 002
0043 .0021 .0027
0016 004
0025 0023
0.021 .012 .017 .01 .0085
037 . 015
02 .019
0094 .0073 .012 . 025 .013 .0035 .011 01
0 0 0 0 0 0 0
0012 0 0 0 0
002 0 0 0 0 0
0.022
019 015 022 015 038 018 028 033 0076 0072 024 038 031 0078 018 0057 023 084 022 056 046
019 034 0041 .007 0095 012 .017 .0013
0.0081 .0024 004 .0028 .0017
01 .0021 0053 .012 0031 0059 .0032 .0044 .0074 .0042 .0013 .0027
013 022 .005 011 0063 0043 . 019
0032 .0033 .0033 01 025 027
039 01 .035
006 .04 0063 027 053 011 023 018 037 038 036
044 021 02 02 015 022 025 014 . 02 026 037
0.02
0.015 .019 .04 .015 .017 0 0061 0087 022 0 . 026
018 .012 .01
039 016 . 015 005 .013 0076 027 01 03 0 .022
0032 .0053
. 012 .015 .013
0067 012 038 04 029 011 011 0 032 0 046
0 035 0 013 .011 .057
0049 .035
.012 .043
0 037 0 028 0078 026 0 05
02 051 26 .1 0 . 068
003 .017
056 0 .053
0 .033
0 .026 01 ,085 . 05 027 027
1.3
.65 1.3 1.5
.8 1.4
.57 1.0
. 56 1.4
0058 0038 .016
005 .012 .018 .0047 0037 011 01 012 .0043
0038 .0039 0017 02 0058 .01 .0085 017 022 .015 02 04 009 .014 .01 .0062 . 025 .017 .015 .0074 .011 .017 .054 .0063 .0081 .0073 .0094
0001 .0025 0029 016 .0035 .0028 . 0014 .0076 .0054 0049 .0017 . 0051 .0008 .0007 .0073
0022 .0038 .0065 .0057 0025 .0045 0038 .0014
0021 . 0051 .0037 .0059 .0025 .0068 0038 0037 009 .0052 0017 0053 .012 .013
0023 .0034 .0024 003 0018 0043 0016 002 0031 011 01 0037 008
081 .0029 .003 .008 . 0051
007 .0062
0098 .0034 .0034 .015
067 .0011 .0005 .0043 0042
.17 027 078 065 043 05 035 065 014 1 11 065 11 055 18 1 .052
22 .1 .032 17 11
056 .018 . 034
035 . 045 .047 .026 .032
022 .033
039 .024
016 .02 .023
026 .017 .039 .04 .032
017 .02 .024
.011 .0018 0074 007 0049 02 0032 .0047
.1 038 061 02 05 053 013 021 046 039 078 032 091 1 051 027 058 05 041
.0024 .0013 .0025 .004 .0023 0 0034 0022 0078 0073
0042 .0019
0
.0019 .0024 .0027 .002 .0028 .003 005 0078001 0
.019 . 031
0031 .0037 009 0028 .015 .0076 .035 .011 .008 .03 .044 0015
.69 .5
03 .73 57 81
74 1.4
64 38 41 57
025 013 011 028 0085 031 024 042 .021 031 062 .09 .015 021 041 021
051 031 04 042 045 012 .011 .025 .02
022 02 02 .024
036 .039 .025 .026 .03 .021 .025 .023
Page 21
TABLE 4. — Average minor-element content of the ash of the columnar samples of coal--Continued
Tenn-V.K. Tenn-Re-S Tenn-Va-s. Ga-B-5 Ga-B1-5 Ga-W-4. Ala-Mi-B[R] Ala-Mi-B Ala-T-B. Ala-TH-B Ala-Mi-Mi. Ala-T-Mi Ala-TH-Mi. Ala-Da-P
Ala-G-P*
Ala-G-NP
Ala-G-A. Ala-M-N. Ala-Ga-ML. Ala-Ma-J. Ala-Mai-J. Ala-De-BC. Ala-Ga-BC. Ala-H-BC. Ala-BD-W Ala-Z-M. Als-Z-M3. Ala-Z-M3* Ala-FtP-UC. Ala-Ft P-UC Ala-E-BC*
8. 91 7.58 6. 56 3. 12 2.83 1. 47 3. 43 7. 93 3. 89 4. 95 3. 30 4. 47 3.01 3. 58 3. 63 7.54 5. 78 13.77 4.85 4. 87 3. 02 1. 71 4. 05 3. 15 4. 89 4.42 4. 51 5. 62 5. 86 2, 86 5. 69
.58 1.5
38 36 76 04 91
3
6552 1.9
0.0047 .003 .0005 .007
0028 .0035 .0091 .0058 .007 .0046 .0068 .0046 .0064 .003 .0045 .002
0029 .0024 .003 .0078 .003 ,015 .0064 004 .0017 .0017 .0025 .0027 .007 .007 .0055
0.0043 .004 .0038 .0043 .017 .049
058 .042
011 ,015 .0074 .017 .012
01 ,008 .006 .007 .0035
0084 .0097
012 .005 .009
016 .005 018
0.03 .03 .023 033 047 .047 . 13 .042 .031 .094 .028 04 036 .053 055 02 051 028 .088 .058 .088 11 045 04 022
. 078
.066 .065 .03 02 025
047 028 043 028 .017
017 0025 023 016 025 026
0.0063
.004 0 .004 .0015 .002 .0004 . 023 .0007 .004 .007 009
011 008 .0065 0
006 .006 003
036 .0016 .072 .0047 .0013 .001 .015 .006 0 .02
.013
0083 .007 006 0026 .013 0012 0035 013
.0095 .042 . 027 042 09 02 .022
031
. 037 .04 029 .03 .028 .015 036 01 026 032 .043 .047 .03 .022 021 018 018
.0034
0 .0017
0012 0
.0025 0 O 0 0 .0008 .0018 . 002 .0006 .001
021 03 028 02 034 012 026 017 053 028 035 033 03 025 023 035 033 .025 .04
01 .015
100
48 100 100
62 100
74 100 55 36 45 35 10
5
.0077 .015 .0074 016 01 0024 0066 .0052
014 .0059 .0045 .015 .011 .004
003 .013
008 .005 005 005 .005
.5
. 57 1.1 . 41 57
71 1.3 .6 .3 3 65
.022 .021 .057 .1 .08 ,055 .025 .02
022 .025 007 008 .015
076 023 031 017 032 028 02 02 02 02
29 .015 .0075 011 006 008 013 002 005 0025
022 02 .015
025 , Ꭴ23 . . 025 .02
02 .019
\ * \ . \ TABLE 5. Average minor-element content of the columinar samples of coal [0, below liniit of detection; leaders indicate no data for element; *, not used in computing rogional averages. Location of samples shown in table 1]
Table 5.— Average minor-element content of the columnar samples of coal--Continued
TABLE 6.- Average minor-element content in parts per million, of the floated and
whole coals
TABLE 7.- Average minor-element content, in parts per million, of the columnar
coal samples and ash fractions
tions than in the whole coal samples are, for the most part, those found to have an affinity for organic matter in previous work [Zubovic and others, 1961b].
Tin is a notable exception and appears to be about twice as highly concentrated in the float fractions as in the whole coal samples. Germanium, the element having the highest organic affinity, of those considered, is notably lower in floated fractions of coals from Alabama than in whole coal samples from the same State. This can be attributed to the fact that in the initial screening process samples high in germanium were analyzed without any separation of the inorganic matter.
COMPARISON OF VITRAINS, FUSAINS, AND KETTLE-BOTTOM COAL
WITH BLOCKS OF WHOLE COAL
The analyses of three vitrain samples, four fusain samples, and one kettle-bottom coal sample and the data on the blocks of coals from which these samples were extracted are given in table 8. The data on the kettle-bottom coal are compared with those from the top block from the columnar sample. It would be expected that because vitrain is relatively purer coal compared to the blocks of whole coal, the vitrains should contain larger amounts of those elements with a highorganic affinity and lesser amounts of those with a low-organic affinity. This expectation is not supported by the data and may be due to the large vertical variability of the minor-element content of the coals.
Many elements having a high affinity for organic matter in coals are present in lower concentrations in fusains than in the block coal samples [table 8]. These elements include vanadium, gallium, yttrium, boron, and to a lesser extent, beryllium and nickel. As fusains are considered to have undergone a high degree of degradation of the organic molecular species, which originally made up the tissues of the material from which the fusains were derived, it may be expected that fewer organic ligands would be available for complex formation. This may, at least partially, account for their low minor-element contents of elements with a high organic affinity.
Chromium and cobalt occur in lesser amounts in two of the four fusains than in the corresponding block samples [table 8]. Their position is thus intermediate as it is in the organic-affinity series [Zubovic and others, 1961b]. Copper, molybdenum, and lanthanum, which are at the lower end of the series, are generally equally or more highly concentrated in the fusains than in the block samples. Thus, the relation shown by these elements in their distribution between fusain and the whole blocks of coal follows the general pattern to be expected from the organic-affinity series.
The kettle-bottom coal and the nearest block of coal from the bed underlying it also show relationships supporting the organic-affinity series. The kettle-bottom coal is purer than that from the block. Germanium, vanadium, nickel, and chromium are considerably more highly concentrated in the kettle-bottom coal; beryllium, titanium, cobalt, gallium, and yttrium are somewhat more highly concentrated; whereas copper, molybdenum, and lanthanum are less highly concentrated in the kettle-bottom coal than in the block sample. Boron, , which, on the basis of the organic-affinity series, might be expected to be more highly concentrated in the purer kettle-bottom coal, is actually present in a much lower concentration.
COMPARISON OF BLOCKS OF COAL WITH INCLUDED PYRITE
Twelve samples of the handpicked pyrite from blocks of lower and middle Kittanning coal of Ohio and Maryland were also analyzed [table 9]. Beryllium, vanadium, boron, chromium, gallium, germanium, molybdenum, tin, and lanthanum were not detected in any of the samples. Yttrium was found in one sample [O-SC14-11K-9 py]. Zinc was found in 3 samples, cobalt in 4 samples, nickel in 9 samples,
Page 22
Most of the elements high in the organic-affinity series are more ighly concentrated in kettle-bottom coal than in a less pure block f coal collected just beneath it. Boron is an exception.
Coals of the Apalachian region appear to contain less zinc, boron, nd tin than coals of the Northern Great Plains or Eastern Interior egion. No other significant differences were found in comparing he coals of these three regions.
idams, G. I., Butts, Charles, Stephenson, L. W., and Cooke, Wythe, 1926,
Geology of Alabama: Alabama Geol. Survey Spec. Rept. 14, 312 p. Averitt, Paul, 1942, Coal fields of the United States, U.S. Geol. Survey map,
scale 1:2,500,000.
1961, Coal reserves of the United States-A progress report, January 1,
1960: U.S. Geol. Survey Bull. 1136, 116 p. - Dieke, G. H., and Crosswhite, H. M., 1943, The use of iron lines as intensity
standards: Optical Soc. America Jour., v. 33, p. 425-434. Glenn, L. C., 1925, The northern Tennessee coal field: Tennessee State Geol.
Survey Bull. 33-B, 478 p. Headlee, A. J. W., and Hunter, R. G., 1955, Characteristics of minable coals of
West Virginia, pt. 5, The inorganic elements in the coals: West Virginia
Geol. Survey Bull., v. 13A, p. 1-131. Horton, L., and Aubrey, K. V., 1950, Distribution of minor elements in three
vitrains from the Barnsley seam: Soc. Chem. Industry Jour. [London],
v. 69, supp. no. 1, p. 841-s48. McCalley, Henry, 1900, Report on the Warrior Coal basin: Alabama Geol.
Survey Spec. Rept. 10, 327 p. McCallie, S. W., 1904, A preliminary report on the coal deposits of Georgia:
Georgia Geol. Survey Bull. 12, 121 p. McFarlan, A. C., 1943, Geology of Kentucky: Lexington, Ky., University of
Kentucky, 531 p. Shotts, R. Q., 1954, The identity and equivalency of persistent coal zones, sand
stone beds and conglomerates of southern Tennessee and the plateau region of Alabama, based upon a study of the literature: Alabama Acad. Sci.
Jour., v. 26, p. 37–46. Stadnichenko, Taisia, Murata, K. J., Zubovic, Peter, and Hufschmidt, E. L.,
1953, Concentration of germanium in the ash of American coals, a progress
report: U.S. Geol. Survey Circ. 272, 34 p. Wanless, H. R., 1946, Pennsylvanian geology of a part of the southern Appa
lachian coal field: Geol. Soc. America Mem. 13, 162 p. Zubovic, Peter, Stadnichenko, Taisia, and Sheffey, N. B., 1960, Comparative
abundance of the minor elements in coals from different parts of the United States, in Short papers in the geological sciences, U.S. Geol. Survey Prof. Paper 400-B: p. B87–B88.
1961a, Geochemistry of minor elements in coals of the Northern Great Plains coal province: U.S. Geol. Survey Bull. 1117-A, 58 p.
1961b, Chemical basis of minor-element associations in coal and other carbonaceous sediments, in Short papers in the geologic and hydrologic sciences, U.S. Geol. Survey Prof. Paper 424-D: p. D345-D348.
Page 23
Table 6. Average minor-element content of the coal of the columnar
samples..
7. Comparison of minor-element content in floated and unfioated
coal..
8. Comparison of the average minor-element content of coal from
the Western and Eastern regions..---
9. Average contents of minor elements in 44 un weathered and
4 weathered coal samples, computed by two different methods.
10. Average content of 15 minor elements in columnar samples of
3 coal beds...
11. Average minor-element content of some coal beds sampled...
Page 24
Table 1.---Location and descriplion of the coal samples
Mo-BN-B. Mo-BS-B MO-B-Mu. Mo-P-T.
18
Macon. 18 .-do. 5 do 10 Henry
Bevier Coal Co. Bevier mine, Bevier.. Bevier Formation ! Bevier South pit.
„do!
do. North pit
Mulky Formation 1 Mulky. Power Coal Co. mine, 2 miles north of Tebo Formation ... Tebo...
Germantown. Sinclair Coal Co. Tiger mine, near Bandera Formation... Mulberry
Hume.
Patch Coal Co. near Welch: No. 2 mine..
Senora Formation. [Forsythe above Broken
Arrow bed.] No. 1 mine..
.do.
Broken Arrow [Crowe
burg]. Rogers County Coal Co., scc. 1, T. 22 do.
..do. N., R. 16 E. McNabb Coal Co. mine, 2.6 miles ..do.
...do. northwest of Catoosa. Ben Hur Coal Co, Blackstone mine, ....do.
Henryetta [Croweburg]... 1 mile north of Henryetta. Leavell Coal Co. Bluebonnot mino, Boggy T'ormation Socor.
sec. 32, T. 12 N., R. 19 E. Lee Strip mine, sec. 28, T. 7 N., R. 16 E. do.
Jones Crook [Bocor]. Puro Coal Co. mine, 8W 748 W X4 moc. Savanna Formation... Cavanal.
4. T. ON., R. 26 E. Ballalaw Atripping Co., 14 miles south MeAlonter Formation. MoAlester -Stiglor
of Ballalaw.
Northside Coal Co, mine, sec. 29, T. 8 Savanna Formation... Paris.
N., R. 26 W Spillway of Horsehead Dam, SEYA ...do.
Unnamed bed 34 ft above NEX sec. 3, T. 10 N., R. 25 W.
Charleston bed. Mine entry 60 ft south of above sample ..do
Charleston locality. Abandoned strip pit, center east line
do. SW44 sec. 32, T. 8 N., R. 28 W. Skidmore Bros. Coal Co., sec. 6, T. 10 ..do.
.do. N., R. 23 W. Quality Excelsior Coal Co. Quality McAlester Formation. Upper Hartshorne. No. 12 mine, 1/4 miles northeast of
Hackett. Bates Coal Co. strip pit, center sec. 22, ..do.
Lower Hartshorne. T.3 N., R. 32 W. Abandoned strip mine, sec. 22, T. 5 do.
.do. N., R. 31 W. Abandoned strip mine, NWASW14 .do.
do sec. 9, T. 4 N., R. 30 W.
See footnotes at end of table.
TABLE 1.—Location and description of the coal samples—Continued
1 Searlght [1968]. 2 Sample submitted by Boyd R. Haley, U.S. Geological Survey. * South of area shown in figure 2. COAL BEDS SAMPLED
The names of the coal beds sampled and the number of samples - collected from each bed are shown in table 1; however, identification : of some of the beds is uncertain. The two samples of Iowa coal
may be from the Mystic bed, but the local names "Mamouth” and “Kirkville” are used in table 1. One sampled coal bed from Oklahoma [OK-Pa-Fo, loc. 6] lies above the Broken Arrow bed and, therefore, could be from the Iron Post bed; however, the mine operator called it the Forsythe bed, and this is the name we have shown in table 1. We assumed that the McAlester and Stigler beds correlate, as suggested by Trumbull [1957], and we have called them the McAlester-Stigler bed in table 1.
The relative stratigraphic position and the correlation of some of the Pennsylvanian coal beds are shown on plate 1.
The Oklahoma-Arkansas basin was the most throughly sampled area, primarily because of our interest in the relation of coal rank to the minor-element content of the coal, but also because more mines were operating and could be sampled. The coals of Iowa, Missouri, and the northern and southwestern parts of the Oklahoma coal fields are high-volatile bituminous in rank [fig. 2]. The coals, in the central and eastern parts of the Oklahoma-Arkansas basin are low- to medium-volatile bituminous in rank and those in the extreme eastern part of the basin are semianthracite in rank.
SAMPLE PREPARATION AND PROCESSING
Samples were collected by cutting out vertical columns from a coal bed. The columns were broken into a series of measured and Jabeled blocks to facilitate handling, shipping, and reassembling in the laboratory. Thicknesses of the blocks were determined primarily by changes in the macroscopic lithology of the coal. column appeared to be largely uniform, it was broken into blocks about 0.5 foot thick. Throughout this paper, “columnar sample” refers to the entire sample of a coal bed, and "block sample” refers to an individual part of a columnar sample. Composite samples were made only from those blocks that were in sequence and whose ash contents were reasonably uniform, so that the principal differences in depositional character throughout the bed would be preserved.
A part of each block sample was ground to pass through a 100
mesh sieve. Ten grams of each ground sample was placed in a cold muffle furnace. The temperature in the furnace was gradually raised to 450°C and was held at that level until all the organic matter was oxidized. A rapid spectrophotometric analytical method, using phenylfluorone as the reagent, was used to determine the approximate amount of germanium in the ash of each block sample. The amount of molybdenum in each sample was determined by the thiocyanite method, which is rapid and produces probable errors of 30 percent or less [Zubovic and others, 1961, p. 20]. The ash of individual samples that contained large amounts of these two elements was then analyzed spectrographically. Separate splits of the block coal samples that contained small quantities of these two ellements were combined to form composite samples which were then ashed and spectrographically analyzed for 15 elements.
Early in the investigation we noticed that many of the elements were undetected in the analyses of ash samples from coals that contained 15 percent or more ash. Also, during sampling we noticed that at almost every mine some method was used to clean the coal. Therefore, we tried to eliminate as much extraneous mineral matter in the coal samples as possible so that the composition of the samples would approximate that of coal produced by most of the mines and used by the principal consumers, as any possible large-scale recovery of elements would be from the ash of such coal.
In this study, 27 percent of the samples were floated. Table ? 2 lists the block samples that were floated and the percentage of the original block that floated. During the initial breaking of the samples, all removable pyritic, calcitic, and clayey parts were picked out by hand. In addition, coals that contained more than about 8 percent ash were centrifuged in a flotation medium of carbon tetrachloride and ethyl alcohol. The specific gravity of the flotation medium used for each sample depended upon the ash content of the coal. Coals that contained less than 10 percent original ash were floated on liquids having specific gravities of 1.32 or less. Coals that contained more than 10 percent original ash were floated on progressively denser liquids as the ash content increased.
Flotation mediums of different densities were used to get the maximum amount of coal into the floated fraction. In many flotation runs, however, the use of fairly high density liquids on high-ash microbanded coal still resulted in low recoveries. The effect of flotation on the minor-element distribution is discussed in detail in a later section.
Page 25
5. 10 6. 54 5. 65 3. 88 3. 60 1.72
75. 1 73. 8 68. 1 73. 6 87.6 90 83.7 51.8 50. 6 23. 6 29.3 53. 6 10 40.6 58. 1 53. 8 63.6 62.5 41. 3 88. 1 10.7 28. 6 35,2 32. 8 75.8 15 52. 3 16 43.8 32.5 82. 7 87.4 16. 2 78.5 55. 3 54.5 64.5 83.5 50.9 18.9 64.5 47.2 13. 2 15.1 47.7 59. 1 35.3 45.9 32 56.5 51
1. 32 1. 36 1. 36 1. 35 1.32 1.32 1. 32 1. 32 1. 32 1. 30 1. 36 1. 32 1. 30 1. 34 1. 32 1. 32 1. 32 1. 30 1. 34 1. 32 1. 32 1. 32 1. 32 1. 32 1. 32 1. 32 1. 32 1.32 1. 32 1.32 1. 36 1.32 1. 30 1. 34 1. 32 1. 34 1.32 1. 30 1. 32 1.30 1. 32 1. 32 1.30 1. 34 1.34 1.32 1.32 1.32 1. 32 1.32 1.32 1. 32 1. 40 1. 40 1.42 1. 58 1. 58 1. 40 1. 58 1. 58 1. 40 1. 40
2. 42 3. 36 2. 98 5. 87 3. 02 2. 07 4.70 3. 16 2. 61 2. 13 1. 28 2. 74 3. 25 1.69 3. 91 3. 16 2. 22 2. 23 3. 40 3. 25 3. 90 3. 73 3. 50 5.80 2. 95 1.36 6.71 1.72 3. 96 3. 68 1.27 2.09 4.60 1.58 2. 39 1.48 2. 96 3, 59 2.04 1.33 1.86 1.87 3.31 2. 46 2. 66 12.41 13. 61
4.93 16. 60 6. 47 4. 16 12.81 12.23
4. 33 12. 19
QUANTITATIVE SPECTROGRAPHIC ANALYSIS The quantitative spectrographic procedure used in the analysis of the coal-ash samples bas been described in detail [Zubovic and others, 1961, p. 18-20]; therefore, the method is only briefly outlined here.
The total-energy method, employing direct-current arc excitation of samples and synthetic standards, was used. The spectra of samples and standards were recorded on photographic plates that cover the wavelength interval 2300 A-4700 A with a dispersion of 5 A per millimeter. The transmittances of the analytical lines were measured with a microphotometer, and the photographic plates were calibrated by use of a set of homologous iron lines for which relative intensities were known [Dieke and Crosswhite, 1943]. Synthetic standards were used to construct analytical curves relating the Jogarithm of intensity of analytical lines to the logarithm of concentration. Concentrations of the various elements were determined from these curves.
The different limits of detection of the elements listed in table 3 resulted from the use of different instruments and laboratories.
! Limits of detection for the samples from Iowa, Missouri, northern Oklahoma, and some samples from the Oklahoma-Arkansas basin.
2 Limits of detection for most of the samples of the Oklahoma-Arkansas basin.
The analytical results are generally the average of two single determinations. The coefficient of variation for the mean of such duplicate determinations for all the elements averages about 15 percent and ranges from 10 to 20 percent, depending upon the nature of the ash, the element, and the concentration of the element.
Analyses for 15 elements in the ash of 225 samples, in 2 coalified logs, and in 1 shaly coal are presented in table 4.
The average minor-element content in ash of each columnar sample is listed in table 5; the average minor-element content, in parts per million, for each columnar sample of coal is listed in table 6. The contents for 49 of the columnar samples are weighted averages based on the thickness of each analyzed block or composite sample. For three columnar samples [Ia-L-K, Mo-BS-B, Ark-M-Le], arithmetic averages of the analyzed blocks are given.
In the following discussion it must be kept in mind that most samples of high-ash coal were cleaned by flotation and that analytical data from these samples have been mixed with data from low-ash or naturally clean coal. Furthermore, first examination of the data showed marked differences in minor-element content of samples from the Oklahoma-Arkansas basin area and from the Missouri-northern Oklahoma area. A comparison of minor-element content in cleaned [floated] and uncleaned [not floated] samples from these two areas is shown in table 7, and a comparison between minor-element content of coals from the Western and Eastern regions of the Interior province is shown in table 8.
Only eight block samples from the northern Oklahoma-Missouri area were floated. The average compositions of these samples were compared with those of 28 samples of unfloated coal from the same columnar samples. In the floated samples, the average contents of boron, titanium, and yttrium were significantly greater than in the unfloated samples; the average content of zinc was considerably smaller, and the average contents of most of the other elements were somewhat smaller. In the floated and unfloated samples, the beryllium content was almost identical.
Comparison of the floated and unfloated samples from the Oklahoma-Arkansas basin shows that in the floated samples the average contents of cobalt and nickel were considerably smaller; the average contents of beryllium, copper, zinc, gallium, and lanthanum were slightly smaller, whereas the average contents of vanadium and tin were much greater and the average contents of the other elements were slightly greater. In the floated coals from both the northern Oklahoma-Missouri area and the Oklahoma-Arkansas basin, the average contents of cobalt, nickel, zinc, copper, lanthanum, and perhaps gallium were smaller, and the average contents of boron, titanium, and yttrium were greater.
TABLE 4.--Spectrochemical analyses of 15 minor elements in the ash of block coal samples from the Western region [Figures indicate percent by weight; asterisk, visual estimate; leaders, sample not analyzed; a, b, separates of a single block. Location and description of samples given in table 1]
Coal Thick- block ness sample [feet]
No.
3. 36 2. 57 4. 08 2. 54 4. 70 6. 54
0005 0005 0005 0005 0005 0005
See footnotes at end of table.
Page 26
4.--Spectrochemical analyses of 15 minor elements in the ash of block coal samples from the Western region-Continued
Coal Thick- block ness sample [feet]
No.
Table 4.-Spectrochemical analyses of 15 minor elements in the ash of block coal samples from the
Coal Thick- block
ness sample [feet]
No.
10.0039 0.0052 *0.01 .0052 .0066
*.02
27 47 20 33 65 35 32 36 38 48
4. 20 2. 74 3. 29 2. 70 12. 81 7.88 3. 30 3, 08 3. 39 10.09
0003 .0001
0002 .0002
0004 .0006
0005 .002
0003 .0007
9 10-14
15 16 17
18 19-20
. 03 01 02 03 0093 022 072 055 02 0084
04 016 . 028
02 .03
02 . 028
06
05 05 .07 . 05 .05
12 . 05
04 . 05
02 02 013 023 026 025 03 014
002 .001 .003 .005 0022 0015 005 .0052 . 005 .0003
01 . 0018 .003 . 014 .020 .003 .0021
0లు : ఉపాసి' కి జd లు సున్నిం? ఆ నే జురాలు ఇలాలు-
.0084 .0009 .0004 0007 0027