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Sewanees Geologic History
The land has changed dramatically through time, in some ways we can know and in others that we can only guess. The early geological history, before the time of the limestones that form the base of the Cumberland Plateau, is rich and varied and will be given short mention here. The ancient Precambrian continental core had seen many collisions and mountain ranges come and go by the dawn of the Paleozoic about 545 million years ago, as Cambrian seas advanced across Tennessee from the east, depositing sandstones and limestones in waters where the first hard-shelled marine organisms flourished. You could drill down to these sandstones 3000 feet below the campus, or you may travel less than two hours and find them at the top of Chilhowee Mountain in the Smokies, above Lake Ocoee.

The Rocks of the Plateau
Following more changes in sea level and two major collisions in the Appalachians, the land was part of a vast Mississippian-age sea with temperatures like today’s Bahamas. Sharks, shedding teeth as they do today, swam above corals and other filter-feeding animals. Graceful long-stemmed crinoids attached to the sea floor dominated the scene, and as these animals died their stems broke apart in tiny discs found in the limestones that form the lower slopes of our Cumberland Plateau. The oldest layer exposed on the Highland Rim, the shelf of farms and fields so prominent below Green’s View, is the St Louis Limestone, named, as are all geologic formations, for the place where it was first formally described. The relatively flat shelf of rock, tilted gently away from the structural dome centered on Murfreesboro, owes its uniformity and lack of degradation to the resistant chert or flint deposits within it. These same cherts define the level of Crow Creek as it emerges from Buggytop Cave. Above the St. Louis is the cave-rich Monteagle Limestone, with calcium carbonate deposits so pure it is actively quarried in Cowan, Sherwood, and elsewhere. The many caves in this layer – Solomon, Wet Cave, and Buggytop to name only a few, testify to its solubility and to the modern humid climate of the area.

Wet Cave has delighted and daunted generations of Sewanee students, as a humorous piece from the 1889 “Sewanee” shows: “It possesses the three great cave merits; its exploration is dirty, difficult, and in some measure dangerous.” The essay describes a “party of ladies and students…armed with candle, lamp, and lantern” encountered the famous mud room that has claimed so many shoes:

“But let the present unfortunate narrator get back to stern reality and Fat Man’s Misery. On emerging–feet first, on one’s back, and down grade, it will be remembered–the explorer falls plump into a mud hole that would put a hog-wallow to shame. At every step the foot and leg sink deep into the clay and are with great difficulty removed.” (1)

Younger Mississsippian layers, in ascending order, are the Hartselle,  Bangor Limestone, and  Pennington Formation. (2) All are primarily marine and contain hard-shelled invertebrates including Rugose (“Horn”) Coral, crinoids (members of Phylum Echinodermata, to which modern starfish belong), and various Bryozoans, filter feeding organisms that include the distinctive Archimedes Spiral. The Bryozoan Phylum has many kin in today’s seas, and is a colonial organism with many dozens of individuals  sharing a larger skeletal edifice. The Mississippian ended 314 million years ago with a marked drop in worldwide sea level. These rocks form the lower two-thirds of the Plateau and include, in addition to the fossil rich limestone, shales rich in clays and a distinctive, tan-weathering dolomite associated with modern tidal flats where evaporation rates are high and the muds exposed at low tide shrink, crack, and curl into mud chips.

Thus the Mississippian section represents a time of shallow-to-shoreline marine conditions. These rocks weather easily in today’s climate and typically form gentle slopes that merge with the Highland Rim below.

During the Mississippian the ancestral Atlantic Ocean, Iapetus, narrowed as Africa slowly approached North America, and by the dawn of the Pennsylvanian Period 314 million years ago the world’s seas had fallen to expose Sewanee to the elements. (3) Hundreds of feet of Mississippian rock were removed and the surface rubble and bedrock were oxidized to a reddish brown. Vast deltas with distributary channels and richly vegetated forests covered much of the area. The first of the Pennsylvanian deposits formed in the lowest-lying areas of the rolling landscape, and some low areas became coal swamps. Lepidodendron, with its diamond-shaped scars marking the loss of leaves, grew as high as 100 feet and left distinctive imprints in the muds and sands that buried its fallen trunks. Calimites, similar to the modern horsetail, was hollow with a distinctively ridged inner stem that typically filled with sand after death. Impressions from a variety of plants are abundant in the sands encasing the coal deposits in Shakerag Hollow and elsewhere. In the shady swamps, huge volumes of fern fronds and branches shed by Lepidodentron, Calimites, and other plants accumulated as peat as giant dragonflies flew overhead. These delta deposits form the domain’s Raccoon Mountain Formation, exposed under the bluff in many places. The thin coals representing the carbon-rich deposits in the swamps produced the local Bon Air bituminous coal, typically exposed as a single seam but in some locations appearing as multiple seams in the sandy and clay-rich deposits that mark the channels and floodplains of the delta. The Bon Air and other coals on the Domain are part of a vast coalfield that extends from northern Pennsylvania to Alabama. Farther north along the Plateau in the West Virginia and Pennsylvania areas there are much greater thicknesses of Pennsylvanian sediments and correspondingly many more layers of coal.

By early Pennsylvanian the world’s continents were in full collision, forming what Alfred Wegner would name Pangea, and the thickening of the crust east of Chattanooga and Knoxville formed an Appalachian Range that rose to heights rivaling today’s Himalayas. West-flowing mountain torrents joined braided rivers in a huge trough extending from Canada to Alabama, flowing southwestward toward the sea. (4) Today’s vast fluvial plains of the braided Ganges and Bramaputra, south of the Himalaya, give us an idea of the immense volumes of sand, gravel, and mud that moved through the Sewanee area.

The sandy layer above the Raccoon Mountain Formation is the Warren Point Sandstone that forms the distinctive local bluffs. The rock is typically more than 99% quartz, a resistant mineral that survived the journey from the eroded highlands much more successfully than the other common minerals such as feldspar. The sandstone displays many southwest-tilting layers called crossbeds, which represent the leading edges of sandbars that were continually moved by the southwest-flowing currents. In cases where the sandbars were not eroded by succeeding currents and floods, but were covered by younger sandbars, the crossbeds were preserved and are our best indication of the direction of the ancient-, or paleo-current. The average dip direction is to the southwest, (5) following the general trend of the giant trough containing the rivers. Individual sets of beds may dip in a large variety of directions that correspond to the wandering, anastamosing channels in the braided rivers that flowed around small islands. Such deposits form today where the supply of sediment is so large that the water cannot carry much of the sediment in dryer times of the year, and simply flows around the deposits made at higher flow times.

The vertical fractures or joints that cut this rock trend northwest and northeast and are essential in preserving the local bluffs: when weaker rocks are eroded below the hard sandstone bluffs, large sections of bluff rock break along this preexisting weakness and either slide slowly or fall rapidly into the forest. The most dramatic local fall in recent times, 1500 feet southwest of Dotson Point, was reported by pilot and Sewanee resident Bill Kershner, and was investigated by three geology students as an independent study. (6) They found that a section of bluff more than 100 feet long had fallen with such force that the loose colluvium of the forest floor below was liquefied, surging down slope to form fault-bounded scarps of fresh earth up to 6 feet high more than 60 feet from the fallen rock. Some of the huge fallen blocks of Warren Point Sandstone overturned as they fell, and other parts of the rockfall simply slipped apart on bedding planes like decks of cards. The authors proposed a triggering mechanism: in addition to the undermining that had occurred through erosion, they found a thirty-year record rainfall of 45.6 inches in the preceding six months. Such a rockfall is a common event over millions of years of geologic time, but within the human timeframe it is relatively rare; no other fall of this magnitude has been reported in the University’s history, although blocks representing prehistoric falls are littered in the forest below Domain bluffs in many locations. In areas near Armfield Bluff the detached sections of bluff are especially notable, with some supporting small ecosystems. The only other rockfall in recent history occurred in Champion Cove in 1977 below the residence of Archie and Lee Stapleton.

The gravelly layer above the Warren Point Sandstone is the Sewanee Conglomerate on which our campus buildings rest.  The ages of zircon minerals in this formation range from 365 million to 2.86 billion years, indicating the wide geographic distribution of rocks contributing their weathered debris to the vast braided river system (7) that deposited the

Sewanee Conglomerate and the Warren Point.  The presence of the Sewanee Conglomerate and younger rocks in locations as far east as Chattanooga and as far west as Short Mountain near Woodbury, Tennessee, give an indication of the minimum width (about 60 miles) of the giant trough in which the sand and gravel were deposited, and this is but a small part of the depositional picture. Archer and Greb (8) see the Sewanee area as part of an early Pennsylvanian system that extended from the Hudson’s Bay area to present-day Alabama.

The most obvious exposure of the Sewanee Conglomerate is inside the University gates at the Sewanee exit near the Shakerag Hollow trailhead; here the crossbeds and quartz pebbles are obvious and beautifully exposed for the generations of Physical Geology students who have sketched this locality for the past 30 years. In the Sewanee area this layer has weathered well back from the bluff, and in many local places accelerated weathering of rock immediately below the conglomerate forms an overhang that was used by native Americans as rock shelters. In other parts of the state, notably Short Mountain, the Sewanee Conglomerate is a bluff-former and much better cemented than it appears on the domain. Its purity, typically more than 99% SiO2, makes it an ideal ingredient for concrete and pure enough to have been mined as a raw material for glass making. (9)

The colors of the Sewanee Conglomerate and Warren Point Sandstone are due to iron-oxide deposits. When the rocks were first deposited a tiny fraction of the sand was made up of minerals containing iron, typically magnetite, hornblende, and biotite. Over time these minerals proved less chemically stable than quartz, and during the process of lithification these unstable minerals dissolved. Groundwater carried the iron deposits throughout the rock, forming the pink (hematite) and yellow-brown (limonite) deposits that lend such character to the campus building stones.

In places much greater concentrations of the iron oxides form liesegang bands, or dark curving zones in the rock where much of the pore space between sand grains is filled with iron deposits.

In some locations on the Domain the sandstone and conglomerate are separated by the relatively hard-to-find Signal Point Shale. This fine-grained mudstone was deposited in a low- energy “backwater” in the major fluvial system already described (10), and has a low enough porosity to localize some of the major campus springs described later the chapter. The soft, easily-weathered nature of the shale and its uneven distribution make it difficult to find, but it may be seen in parts of Abbo’s Alley below the ATO Spring and in the roadside bank at the south end of Kentucky Avenue.

The Whitwell Shale, deposited above the Sewanee Conglomerate, has been almost completely eroded from the Domain, but is remarkable where it still exists. The shale is found in the Lake Dimmick area, where its lack of erosion is largely due to the downwarping of the land into a structural basin after deposition. During the coal mining in the 19th and 20th centuries the bituminous coals of the Richland Seam (variable thickness to 5 feet) and the Sewanee Seam (3 feet thick) were removed from the surface, and the mines are now marked by faint grooves in the ground and piles of spoil rock discarded in the process. On the south side of lake Dimmick, where more mechanized stripping of the Richland Seam took place along a now-wooded ridge, long steep piles of spoil rock covered by healthy yellow poplars run parallel to the high walls formed by mining.

The erosion of the Whitwell Shale from most of the Sewanee Quadrangle and almost all the domain is an important part of University history. When the railroad was brought to Sewanee from the main line of the Nashville, Chattanooga, and St. Louis Railway in 1855 there was an expectation of rich coal deposits; it was soon clear that the thicker deposits were to the north in Grundy County (11), where the Whitwell had suffered less erosion and the Sewanee and Richland Seams were accessible. It is difficult to believe that the land companies would have sold coal-rich lands to the University, at least before a thorough stripping of these coals from the ground. With only the thin Bon Air coal exposed on the domain, along with scattered locations where the Richland and Sewanee seams were available, and with the inconvenient location of the Bon Air coal below the bluff, the land was relatively unattractive to the coal companies and ripe for a gift to a deserving institution.

There is no way of knowing exactly how many additional formations were deposited above the Whitwell Shale, but it is worth sketching a general picture of what most geologists would speculate. The continental collision that initiated the heavy erosion of sediments in the Appalachians and the accompanying deposition of sediments in the trough where the Cumberland Plateau now lies continued for tens of millions of years. If the Whitwell Shale is 300 million years old, and the final assembly of the supercontinent Pangea was 250 million years ago, then we can conclude that the high Applachians were actively growing, weathering, and providing sediments to this area for at least 50 million years after the youngest rocks on the domain were deposited. The time was probably far longer. At any rate, we know that younger Pennsylvanian deposits (conglomerates, sands, shales, and coals) are found northward along the plateau towards Pennsylvania, and that even some younger Permian-age deposits are found in the Allegheny Plateau (a continuation of the Cumberland Plateau). It is reasonable to think that these younger deposits or their time-equivalents covered Sewanee. Another clue to the possible thickness of eroded deposits comes from the bituminous coals on the domain. Coals of this middle rank (anthracite is higher rank, lignite lower rank) indicate burial depths of 8000-10,000 feet at a minimum. Only at these depths are the temperatures high enough to change the original peat from the coal swamps to lignite and then bituminous coal.

Much of the story to this point has focused on deposition. In contrast, the last 200 million years or so of Sewanee’s geologic history have been marked by erosion, and our present landscape gives us evidence of only the very last phases of a process that removed vertical miles of sediment from the land. The process continues in its most dramatic form during large cloudbursts, when steep valleys funnel the rain to the channels so rapidly that the large boulders are able to roll, smack against peers for a few meters, and come to rest again, a little more rounded than before.

We have, then, a few rock-solid clues about the nature of Sewanee’s history during the time from 330-300 million years ago. Later, local peat beds were buried under enough sediment to raise the temperatures to the point of producing bituminous coals. We also have evidence, covered later in this chapter, that the formation of Pangea folded and faulted some of these local rocks about 250 million years ago as part of the last mountain-building episode of the Appalachians. Sometime in the past 300 million years the local rocks, deposited close to sea level, have been uplifted almost 2000 feet. Thus in the overall scheme we know very little of what has transpired in the last 300 million years except by extrapolation from neighboring regions or from analogies from other mountain belts. What we do know forms an intriguing puzzle and encourages our appreciation of the rocks that remain.

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Coal on the Plateau
Coal mining has been an important part of the University’s history. It was the presence of coal on the Plateau that brought the railroad to Sewanee, in 1855, and the absence of significant coal seams that allowed the major mining to rapidly shift northward to the thicker, younger seams of bituminous coal in the Tracy City area (58). This left Sewanee well supplied with modern transportation and unburdened by the major landscape scars that mark large areas to the north where coal is found near the surface of the land.

Long before the railroads reached Sewanee and certainly by the 1830s, there were local coal banks being used by Franklin County residents. Patricia Makris  (59) reports the mention of coal beds and coal banks in an 1834 land grant application by Porter, Logan, and Estill. Some of the coal was exposed at the surface and would have made easy pickings for a home fire grate or a blacksmith.

The earliest significant mines, corresponding to the advent of the railroad, were two and one-half miles beyond Sewanee, immediately north of the crossroads in Midway and also on the highest ground in the vicinity of the Lookout Tower and St. Andrew’s – Sewanee School. (For the modern time traveler driving from Monteagle towards Sewanee, these mines would appear immediately on the right as one topped the highest hill approaching the St. Andrew’s Sewanee School. Dust rising from the Midway mines would be seen rising on the left side of the road.) Forty-seven abandoned mines mark the Sewanee seam in the Whitwell Shale that was exposed here in a 36-inch layer. (60) Wilbur Nelson remarked in 1925 that

“…It was impossible to enter the workings, which were caved in and filled with water. The coal was said to average about 36 inches, and to be easy to work. It can be seen that over most of these old workings the overburden was very small, not being more than 20 feet in many places. It has been thought on this account that if much of the coal was left in these small hills, it might be profitably mined by stripping the overburden with a steam shovel and getting the remainder of the coal very cheaply.” (61)

This kind of old-fashioned mountaintop removal has changed the topography of areas as close to Sewanee as Grundy County. A century and a half after early Sewanee seam mining near the railroad, the practice suggested by Nelson is still a nationally recognized environmental issue in states like West Virginia and Kentucky. Sewanee citizens can be thankful that the forest and microwave towers now surround the old fire lookout on this height of land, and the many subdued mounds of waste rock that dot the hillside, each paired with a collapsed trench, are all that remain to mark the earliest mines of the railroad era.  If more of the Sewanee seam had survived the ravages of erosion here, this would have been a more worthwhile prospect for the Sewanee Mining Company and the ravaging would have been done more quickly with an uglier outcome.

By 1925 a far less productive Richland Seam, also in the Whitwell Shale, was opened in Midway, south of the railroad, near the home of Emile Huntzeker. The seam varies from 0 to 5 feet in thickness, and Nelson describes it as “of poor quality and rashy.” (62) Decades earlier, Safford had identified this seam as the Jackson Coal, found a mile and a half to the south near a small “knoll” now known as Little Mountain.  This area lies just north of present Lake Dimmick, and here Moore (63) shows 22 abandoned mines. Interestingly, Safford identifies this as one of the earliest local mine areas:

“The coal at this point is tolerably good, would be quite so, but for the presence of pyrite….A considerable amount of coal has been taken from this bed up to the time the Sewanee Mining Company commenced their operations.…This bank, with others on this section of the Table-land, and among them the Porter and Logan Banks, was first opened by Abram Van Vleck, a working man, but an intelligent one, having no occasion to cloak his ignorance by calling himself a “practical miner.” (64)

The pyrite mentioned here and other iron sulfides are among the most soluble of the minerals in waste rock associated with coal mining, and are responsible for much of the high acidity in the acid mine drainage that is of concern in modern mining reclamation projects. At Little Mountain the issue was poor-quality coal; in more modern settings the additional issue is streams with acidity too high to support familiar forms of aquatic life.

Twenty-six abandoned mines are still evident below the University bluffline, many with entrances still evident and waste rock piled just downslope from the opening. With one exception (Armfield Bluff) the old workings are found on the north-facing slopes of the Domain from Dotson Point to the head of Shakerag Hollow. (65) (With the geographically challenged reader again in mind, imagine that as you drive towards the University through the stone gates that the mines are still active and the forest has been stripped away. To your right (west) is the deeply carved Shakerag Hollow with its Bon Air Coal mines, with Green’s View beyond it. Rutledge Point mines are in the middle distance, and four miles away lies the westernmost mine in view at Dotson Point.)  Now back in the present, one notices that in many sites yellow poplars have thrived in the acidic environment produced by dissolution of the soluble parts of the waste rock and in the open space of the cleared mine sites.

Coal mining on and under the Domain was not always in the best interest of the landowner. A cryptic 1920 map and letter from University Engineer Robert Black to Vice Chancellor Bishop Knight (66) gives some insight into the running of a University that owns significant natural resources. In the Will Stevens mine above Roark’s Cove Road and under the bluff, three tunnels were dug under University land along the Bon Air Coal Seam, which is well enough developed there for the horizontal addits to average 50 feet in length from the bluff under University land.  Black submitted a clearly executed map showing the extent of the mining tunnels, along with a note that Nancy Stevens (an owner) was present when the map was drawn; he suggests the University take over the mining as payment for the already far-advanced trespass. It seems a fine exercise in pragmatism and forgiveness: with the coal long up in smoke, allow the miner walk free and make the best of it. Five years later Nelson apparently identifies this site as “one mile north of Sewanee on the west side of the road to Alto.” (67) He remarks that the mine belongs to the university and that the coal is 16 to 34 inches in thickness, remarkable for the Battle Creek (an older term for today’s Bonair Coal).

The mines of Shakerag Hollow have largely collapsed, but their mark on the landscape and on the minds of introductory geology students is clearly seen. The students file each semester into one of the safer open entrances off the Shakerag trail, stooping to protect their heads and pausing to let their eyes adjust to the dim interior. On their right is a mined-out slot and shelf a foot and a half high stretching back into the darkness, with old timbers still propping up the ceiling here and there. The underclay, or original soil on which the coal plants grew, lies on the rock shelf exactly as it did as miners crawled into the claustrobia-producing space more than a hundred years ago. The black coal, with yellow – brown stains along the bedding, remains in place on either side of the slot, holding up the ceiling of sandstone where drops of condensation reflect back the flashlight’s beam through old spider webs. Before them stretches the main addit, with several other mined-out shelves in the distance. The class remains close to the entrance and steps with relief into the sunlight where giant yellow poplars, growing on the waste rock since the mine was abandoned, form some of the largest of the Shakerag Hollow trees. In front of the mine is the old tote road, worn flat by human and mule traffic and stretching toward collapsed mines in Rainbow Hollow, farther to the west in Shakerag. The track is overgrown but unmistakable, and the shiny black bituminous coal is underfoot.

The mines of Shakerag are a powerful time machine for human history extending back to the University’s founding, but they also yield some clues about the original forests and mires in which they formed and about mountain building far to the east as North America and Africa collided.

The clues to the coal forests are clearly displayed in the sandstones near the mines. Sandy channels winding through the ancient mires and deltas buried and filled many of the hollow trunks, and the imprint of the bark is still seen in the hard stone. In some cases coal formed from the original bark is there as well, a thin veneer pressed into the geometric pattern of  horsetail-shaped calimites. Within the coal itself the clues are much subtler: studies by Steve Shaver and students of spores and pollen in the Bon Air Coal show the dominance of large lycopsids, scaly-barked trees including Lepidodendron where diamond-shaped leaf scars are arrayed in diagonal spirals. (68) The coals appear to have formed in isolated forest swamps, or mires, that were less than a mile wide. While all of the swamps were within a larger deltaic paleoenvironment, Shaver et al. note that the Armfield mire was far from the channel, surrounded by muddy sediments, and dominated by small lycopsids. In contrast, the Shakerag mire was close to the main river channel, dominated by the large lycopsids typical of most of the Sewanee coals, and occurred in quartz-rich underclays (the “seat rock” in which the coal plants grew).(69)

As for the marks of mountain-building, the coals are only a mere whisper of evidence in comparison to the huge mountain-sized folds that lie in the Valley and Ridge and the Blue Ridge provinces to the east. As stresses died out to the west, deformation was confined to the very weakest rocks, including the coals, and the remarkable aspect of the coals is that they sheared and folded along roughly horizontal planes as the rocks above, the present cap of the Plateau and perhaps two additional vertical miles of rock, were sliding above in a largely unbroken state. Thus the coals in the ShakeRag mines are not typically as blocky and reflective as coals from other regions, but may be folded, sheared, and mixed with the clays on which their parent plants grew. These features are far better developed in some nearby parts of the plateau including Franklin State Forest (70) and Fiery Gizzard, (71) where the stronger sandstones are sheared and folded. Nevertheless the domain rocks are part of the body of evidence that documents this 250-million-year-old collision that marked the formation of the world’s latest supercontinent, Alfred Wegner’s Pangea.

Franklin County coals may have been among the first in the state to have attracted the attention of organized mining companies and railroads, but their staying power is well-represented by the shift of major mining to northern counties within a few years of commencement. In a 1960 analysis of Tennessee coal reserves, Franklin is not listed among the 19 counties with seams at least 28 inches in thickness. By contrast, Grundy County has more than 7.3 million tons or reserves.(72) The lack of economically viable coal may continue to be a blessing for the University and surrounding area: there will never be the temptation to strip the land down to the level of the Sewanee and Richland seams, a practice that has left Grundy County and others with large tracts of acidic ponds and mounds of waste rock. These conditions were so acute in the Ranger Creek watershed in Grundy County in the 1980s that Environmental Protection Agency’s Superfund was employed, providing a good but sobering local example of environmental degradation for Sewaneee students to appreciate.

 – Bran Potter, Professor of Geology

(Excerpted from Chapter 2, “How Firm a Foundation: Sewanee’s Domain” in Sewanee Perspectives, edited by Gerald Smith and Samuel Williamson. Sewanee Sesquicentennial History Project, 2008.)

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1. X.Y.Z., “Sewanee”, September and October, 1889, p. 4 and 5. Archives.
2. James L. Moore, Geologic map and mineral resources summary of the Sewanee Quadrangle, Tennessee: (Nashville, TN, 1983) Tennessee Department of Conservation, Division of Geology.
3. Martin A Knoll and Donald B. Potter, Jr., Introduction to the Geology of the Sewanee, Tennessee Area, in Journeys through TAG, 1998: National Speleological Society Convention Guidebook (National Speleological Society, Huntsville, Alabama, 1998). P. 144-152.
4. Allen W. Archer and Stephen F. Greb, “An Amazon-scale drainage system in the early Pennsylvanian of Central North America:” Journal of Geology, 1995, volume 103, p. 611-628.
5. Ibid.
6. James J. Henley, Amanda J. Cook, T. Carlyle Knox, and Donald B. Potter, Jr., Geology of the 1994 Dotson Point Rockfall,Sewanee, TN, Tennessee Academy of Sciences (Abstract) 1996.
7. William A Thomas, Thomas P. Becker, Scott D. Samson, and Michael A. Hamilton, Detrital zircon evidence of a recycled orogenic foreland provenance for Alleghanian clastic-wedge sandstones: Journal of Geology, 2004, volume 112, p. 23-37.
8. Archer and Greb , “An Amazon-scale drainage system…”
9. James L. Moore, Geologic map and mineral resources summary of the Sewanee Quadrangle…
10. S. A.  Hurd and F.W. Stapor,” Facies, stratigraphy, and provenance of the Warren Point Sandstone (Pennsylvanian), Cumberland Plateau, Central Tennessee:” Southeastern Geology, 1997,  V.36, No. 4, p. 187-201.
11. Wilbur A Nelson, The Southern Tennessee Coal Field: Bulletin 33A, State of Tennessee, Department of Education, Division of Geology, 1925, 239 p.

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56. Margaret Ann Benton, Elise E. Traversa, Anna I. Jones, Deborah A. McGrath, and Robert E. Bachman, Exurban Lakes on the Southern Cumberland Plateau of Tennessee Part II: Metal Stratification and Implications for Water Supply, Abstracts with Programs,  Geological Society of America, vol. 39, no. 2, p. 19.
56a. Kara Allen, Lucy Parham, and Karen Kuers, Aboveground biomass, carbon content and nitrogen cycling for a fifty acre watershed on the Domain of the University of the South: Scientific Sewanee, Abstract 1, 2005.
57. Charles Baird, The Sewanee Water Story, p 4. University Archives,1968.
58. Ethel Armes, The Story of Coal and Iron in Alabama, p. 366, Beechwood Books, Leeds, Alabama, 1987.
59. Patricia Short Makris, The Other Side of Sewanee, Dogwood Printing,(Ozark, MO, 1997).
60. Moore, Geologic Map, 1983.
61. Wilber Nelson, The Southern Tennessee Coal Field 1925, p. 106.
62. Ibid.
63. Moore, Geologic map of the Monteagle Quadrangle, 1979.
64. Safford, Geology, p. 381. Nelson, 1925, also refers to early Little Mountain mines on p. 5.
65. Moore, Geologic Map, 1983.
66.  Robert Black to Vice Chancellor Knight, February 10, 1920, with accompanying map,  University Archives).
67. Wilbur A. Nelson, p.104.
68. Stephen Shaver et al., Petrography, palynology, and paleoecology of the Lower Pennsylvanian Bon Air coal, Franklin County, Cunberland Plateau, southeast Tennessee (Elsevier, International Journal of Coal Geology, 2006. P 17-46.
69. Ibid.
70. Forestry and Geology Senior Seminar, 2006 A Resource Assessment of the Franklin-Marion State Forest, 79 p.
71. Hampton Uzelle and Donald B. Potter, Jr., “Constraints on transport direction of the Cumberland Overthrust, Fiery Gizzard, TN, based on fold and thrust geometry,” Geological Society of America Abstracts with Programs, v. 29, no. 3, p.75, 1997.
72. Edward T. Luther, The Coal Industry of Tennessee, (Nashville, Tennessee, 1960) Department of Conservation and Commerce, Division of Geology, Information Circular No. 10.

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