COA I. /JHPOS/'l~) OF u t ;Ot.' (i/.1 FNfl .\' liS! '! H C I .: - 1'1.. 1FF C IHCKA~IA l"GA lli,U'I', T.OOKOCT >IOU'11'AI:-;, WALKER COL"XT\" GEORGI A , SHOW IXC .\ TYPICAL DI.l:l'l' OF I.OO KOvT SA ::-; D:;T0 ::-;1,;. GEOLOGICAL SURVEY OF GEORGIA W. S. YEATES, State Geologist BULLETIN No 12. A PRELIMINARY REPORT ON THE COAL DEPOSITS OF GEORGIA BY . S. W. McCALLIE Assistant Geologist GEO. W. HARRISON, STATE PRINTER FRANKLIN PRINTING AND PUBLJSHT!\G COMPANY Atlanta, Georgia THE ADVISORY BOARD of the Geological Survey of Georgia (Ex-Officio) Hrs ExCELLENCY, J. M. TERRELL, Governor of Georgia PRESIDENT OF THE BOARD HoN. 0. B. STEVENS HoN. W. B. MERRITT HoN. R. E. PARK HoN. W. A. WRIGHT HoN. PHILIP COOK HoN. JOHN C. HART . Commissioner of Agriculture Commissioner of Public Schools . . State Treasurer Comptroller-General Secretary of State Attorney-General LETTER OF TRANSMITTAL GEOLOGICAL SURVEY OF GEORGIA, ATI.ANTA, January 2nd, 1904. To His Excellency, J. M. TERRELL, Governor, SIR :-I- have the honor to submit a report by Mr. S. W. McCallie, Assistant Geologist, on the Coal Deposits of Georgia, to be published as Bulletin No. 12 of this Survey. Very respectfully yours, W. S. YEATES, State Geologist. (5) TABLE OF CONTENTS CHAPTER THE CARBONIF.EROUS ROCKS OF GEORGIA . Fort Payne Chert Floyd Shale . . . . Bangor Limestone . Lookout Sandstone . Walden Sandstone . Page 9 10 14 16 19 20 CHAPTER II TOPOGRAPHY . . . . 22 Sand Mountain . . 22 Lookout Mountain . CHAPTER III STRUCTURAl, GEOI,OGY OF THE COAL FIEI,DS Major Structural Features . . . Minor Structural Features . . . CHAPTER IV THE CoAL DEPOSITS OF WALKER COUNTY . 34 Durham Coal Mine . . . . . . . 34 Description of Individual Properties 42 CHAPTER V THE CoAL DEPOSITS oF CHATTOOGA CouNTY ss Description of Individual Properties . . ss CHAPTER VI THE COAL DEPOSITS OF DADE COUNTY 6r Description of Individual Properties . 6r CHAPTER VII CORREI,ATION NOTES 96 Lower Coal Measures . 99 Upper Coal Measures . IOS CHAPTER VIII DISCUSSION OF THE CHEMICAL PROPERTIES OF THE GEORGIA COALS . . . . . . . . . . . I I4 (7) T E N N E s s EE _j LEGEND ~ Walden ~ S.mastone ~ LooKout ~ Sandstone ~ Fort PaynP ~ Chert . S t lur ta n 00]] Cam brran Scale M Jes B D Map Showing the. Distribution of lhe Coal Measures of Northwt>s t Georgia, togethe r with the Associated Ro(ks. THE COAL DEPOSITS OF GEORGIA CHAPTER I THE CARBONIFEROUS ROCKS OF GEORGIA The Carboniferous rocks of Georgia are confined to the northwestern part of the State. They are best developed in Dade, Walker and Chattooga counties; though considerable areas occur in Floyd, Gordon, Whitfield and Catoosa. In addition to the above areas, there are four or five small isolated patches of the lowest member of the Carboniferous rocks, in the western part of Polk county.r The latter exposure appears to be a remnant of once extensive Carboniferous strata, covering much, if not all, of the Paleozoic area of Northwest Georgia. The superficial extent of the several areas of Carboniferous rocks, here enumerated, aggregates about soo square miles, which is only a fraction of the entire original Carboniferous area of the State. The Carboniferous rocks of Georgia have been divided by Dr. C. W. Hayes, of the United States Geological Survey, into the following five divisions, named in the ascending order: Fort Payne Chert, Floyd Shale, Bangor Limestone, Lookout Sandstone and Walden's Ridge Sandstone. 2 The three first divisions, here given, belong to the Sub-Carboniferous series; while the two remaining divisions constitute the Carboniferous formation proper, or the Coal Measures. I See Map opposite page 16. 2 Geologic Atlas, Ringgold Folio, U.S. Geol. Surv. (9) IO THE CARBONIFEROUS ROCKS OF GEORGIA THE FoRT PAYNE CHERT, the lowest member of the Sub-Carboniferous rocks, takes its name from Fort Payne, Alabama, at which place it is typically developed. The formation corresponds to Safford's Siliceous Group of Tennessee,' and to Smith's lower division of the Sub-Carboniferous rocks of Alabama, 2 which he designates as Lauderdale or Keokuk Chert. The Fort Payne Chert, as defined by Hayes, rests directly upon the Devonian Black Shale, and is limited above, by the Floyd Shale, or, where that formation is wanting, by the Bangor Limestone. The upper limit of the formation is often difficult to define. Especially is this true, where it is overlain by the Bangor Limestone. In such cases, it passes gradually into the purer limestone above, without any sudden or abhtpt change. Under such conditions, it is often practically impossible to estimate the exact thickness of the formation. This accounts, in a great measure, no doubt, for the wide variation in the estimated thickness of the formation in Northwest Georgia. Hayes, who has made quite a study of the Paleozoic rocks of Georgia, Alabama and Tennessee, places the maximum thickness of the Fort Payne chert at 200 feet, while Spencer places it at sro feet.3 The former estimate, according to my own observation, seems to be more nearly correct. However, the average thickness of the formation in Northwest Georgia would probably not exceed rso feet. At some points in Catoosa county, and also in Whitfield, the Fort Payne chert is reported to attain a thickness of not more than so feet. The Fort Payne chert is a siliceous, calcareous formation ; and, as the name suggests, it carries a large quantity of cherty material. The lower beds of the formation, in places, often consist almost entirely of chert in the form of layers, varying from one to two 1 Geology of Tennessee, pp. 339-351. 35. 2 Tennessee Valley Region, Ala. Geol. Surv., page 3 Geol. Surv. of Georgia, The Paleozoic Group, page 52. THE CARBONIFEROUS ROCKS OF GEORGIA II feet in thickness. These layers frequently have an aggregate thickness of more than 20 feet ; and, at some points, where the underlying shales have been removed by erosion, they give rise to perpendicular bluffs, from IS to 20 feet in height. The chert, forming the individual layers at the base of the formation, is sometimes quite compact; but it is generally of a porous nature, and frequently consists largely of fragments of crinoid stems. In passing along the lower to the upper beds of the formation, the cherty material gradually decreases in quantity, until it finally disappears entirely, or is represented by only a few scattered nodules in the almost pure limestone. The limestone, which makes up the great mass of the Fort Payne formation, is in most cases quite siliceous; but, at some points, it consists of beds of almost pure calcium carbonate. Limestone, of the latter character, is to be seen at the quarry near Rising Fawn furnace, where large quantities of the stone were formerly obtained for fluxing purposes. Some beds of the limestone often contain little or no cherty nodules; nevertheless these beds, in many places, are found to carry a high percentage of silica. The siliceous material, in this case, is found, upon microscopic examination, to occur in the form of minute particles, forming small clusters or bunches, irregularly distributed throughout the calcareous mass. In the weathering of beds of this character, the surface often becomes encrusted, to the depth of a quarter of an inch or more, with a dark brown or chocolate-colored coating, consisting mainly of silica. The weathered product, when powdered, forms a very fine, sharp grit, partaking of the nature of tripoli. The following is a chemical analysis of a specimen of Fort Payne limestone, showing microscopic clusters of siliceous particles, made in the Survey laboratory, by Dr. Thomas L. Watson, formerly Assistant State Geologist:- 12 THE CARBONIFEROUS ROCKS OF GEORGIA Calcium Carbonate __________ ---------------- 3744 Magnesium Carbonate ________________________ 2595 Iron Sesqui-oxide_______________________ ____ o.69 Alumina___________________________________ 1.38 Insoluble Residue_------ _____ --------------- 3549 Total ______ ~ ____________ ------ _____ - ____ I oo. 95 Associated with the lower beds of the Fort Payne chert, often occur thin layers, or partings, of shale, varying from a few inches to a foot or more in thickness. These shales usually have a greenish color, and weather into a tough plastic clay. The most marked, distinguishing cliaracteristic of the Fort Payne formation is the great abundance of chert. This material is always quite plentiful along the outcropping of the formation ; and it often covers the surface to the depth of several feet. This chert is readily distinguished from the Knox Dolomite chertt which it frequently closely resembles, by being fossiliferous. The fossils consist mainly of the fragments of crinoid stems; though coral and other organic remains sometimes occur. In weathering, this cherty material breaks into irregular fragments, well suited for road-surfacing. The distribution of Fort Payne chert in Northwest Georgia is confined to narrow bands or zones, outcropping along the base of the mountains and ridges, formed of Carboniferous strata. It is well exposed at the base of Sand, Lookout and Pigeon mountains, and Taylor's ridge, as well as along the foot of Horn, John's and Lavander mountains, further to the east and s<;mth. As a general rule, the outcropping of this formation, owing to the slow weathering of its siliceous materials, gives rise to a narrow, sharp, serrated ridge, or chain of hills, running parallel with the main mountains, or ridges. In some instances, these hills, or minor ridges, sit back quite a distance from the base of the major ridges~ or mountains, in which case, there is always a narrow, fertile valley intervening. The ridges, formed by the Fort Payne chert,. THE CARBONIFEROUS ROCKS OF GEORGIA 13 sometimes attain an elevation of 400 or soo feet above the general level of the valley; and, at many points, they have received local names which are usually of a descriptive nature. 1'hus, Pudding ridge, of Dade county, and Shinbone ridge, of Walker, are names given to the more prominent parts of these cherty ridges. Economically considered, the Fort Payne formation of Northwest Georgia has been supposed, heretofore, to be of but little commercial importance. With the exception of its chert, which is now being used to a considerable extent for road-surfacing, probably the most important material, of economic interest, in the formation, is its fire-clays. These clays, having resulted from the weathering of the more siliceous beds of the formation, are frequently found in considerable quantities along the slopes of the cherty ridges. A good exposure of a clay deposit, of this character, is to be seen in some old prospect-pits near the Alabama Great Southern Railroad, about one mile south of Rising Fawn. Just .across the Alabama State-line, in the vi"cinity of Valley Head, are located the extensive fire-clay mines belonging to the Montague Clay Works, of Chattanooga. The clays here exposed are similar to those occurring near Rising Fawn, and have a like origin. Dr. Reis, in describing the clays at the former place, says: "Several -qualities of clays are obtained from the mines; but they are not restricted, in any case, to certain layers. The following sample, tested, is what is known at the mines as the first-grade, and its -refractory character is not by any means low.'' 1 The sample, here referred to by Dr. Reis, was a rather coarse-grained, white, sandy .clay, showing the following chemical composition : ~ 1 Geol. Surv. of Ala., Clays of Alabama, by Heinrich Reis, page 147. THE CARBONIFEROUS ROCKS OF GEORGIA Silica____________________________________ _ 82.040 Alumina _________________________________ _ I2.IJO Ferric Oxide------------------------------ trace Lime ________ --- - - . _- -- . - .. - ------- -- --- ---- trace Magnesia __________________ .. _____________ _ 327 Alkalies _________ . ________________________ _ .6oo Ignition __________________________________ _ 4-325 Total ________________________________ _ 99462 Associated with the refractory clays here described, often occur potter's clay and halloysite. The last named mineral, according to Spencer,' is found on the Blivens property near Rising Fawn,. and on the east side of Taylor's ridge, in the vicinity of Subligna. In addition to the clays, the Fort Payne chert, in places, carries impure deposits of limonite. These deposits, however, are usually of limited extent, and appear to be of but little commercial importance. Gypsum, in the form of small pockets or nodular masses, also occurs at a few points in the siliceous limestones of the formation. Good hand specimens of this mhteral may be collected from the dump at the west end of the railroad tunnel at Pigeon mountain. THE FLOYD SHALE.- The Floyd Shale, as is above stated, lies immediately above the Fort Payne Chert, and is so called from the county of Floyd, where it is well developed. The formation~ which is always valley-making, covers a considerable area both in Chattooga and in Floyd counties ; and, according to Spencer, it has a thickness of r,soo feet. 2 The Floyd Shale, as the name implies, consists chiefly of shales; though, in places, limestone, and even sandstone, occurs. The latter beds are well developed in Alabama, where they are termed "Oxmore Sandstone." The shales, which are of a yellow or black color, are often quite calcareous ; and, in places, they become very fossiliferous. The calcareous type, of this shale, is well developed in West Armuchee 1 Geol. Surv. of Georgia, The Paleozoic Group, by J. W. Spencer, p. 212. 2 Ibid., p, sz. THE CARBONIFEROUS ROCKS OF GEORGIA IS valley, in the vicinity of Green Bush, where it is associated with thin beds of limestone. Both the shale and the limestone in that district are often highly fossiliferous, the most abundant remains being blastoids and bryozoa. The former fossils are usually siliceous, and, at some points, they are found in considerable abundance in the residual clay; while the latter are of a more calcareous nature, and occur as delicate markings embedded in the partially weathered shale. In addition to these fossils, corals and bivalves are also quite plentiful; and occasionally they are well preserved. The district, here referred to, is probably the best locality to be found anywhere in the State for the collection of fossils from the Floyd Shale horizon. The black shale of the formation differs from the above shale, not only in color, but also in the lack of fossils and calcareous material. The black shale is highly carboniferous, and it is often difficult to distinguish it from the Devonian black shale, which it frequently closely resembles. At some points, as in the vicinity of Sugar valley, this black shale has been taken as an indication of coal, and has been prospected at considerable expense by drilling. Hayes, in speaking of the sandstone of the Floyd Shale, says:-" East of Taylor's Ridge, there is a thin-bedded, more compact sandstone, sometimes highly fossiliferous, which passes gradually into the Floyd shales above and below." r In Te:X:as valley, this sandstone gives rise to two ridges running parallel with the Fort Payne chert ridges. The one mineral, of economic interest, associated with the Floyd shale, is the brown-iron ore. This ore, which has been somewh.at extensively worked on the east side of Horn mountain, a short distance west of Sugar valley, occurs near the base of the formation; and, in places, it probably belongs to the Fort Payne chert. Brown-iron-ore deposits, similar to the above, are also to 1 Geology of North-East Alabama and Adjacent Portions of Tennessee and Georgia, p~ 47. THE CARBONIFEROUS ROCKS OF GEORGIA be seen in Redwine Cove, about three miles northwest of Carbon