I
GEOLOGICAL SURVEY OF GEORGIA
S. W. McCALLIE, State Geologist
A PRELIMINARY REPORT
ON THE
OIL PROSPECT
NEAR
SCOTLAND
TE.LfAIR COUNTY
GEORGIA
BY J. P. D. HULL and L. P; TEAS
Ass!stant State Geologists
Atlauta, Ga. INDEX PRINTING COMPANY,
1919
I
GEOLOGICAL SURVEY OF GEORGIA
S. W. McCALLIE, State Geologist
A PRELIMINARY REPORT
ON THE
OIL PROSPECT
NEAR
SCOTLAND
TELFAIR COUNTY
GEORGIA
BY ' J. P. D. HULL and L. P. TEAS
Assistant State Geologists
Atlanta, Ga. INDEX P~INTING COMPANY,
1919
THE ADVISORY BOARD
OF THE
Geological Survey of Georgia
IN THE YEAR 1919
(Ex-Officio)
(
Hrs ExcELLENCY, HUGH M. DORSEY ......... Governor of Georgia PRESIDENT OF THE BOARD
HoN. S. G. McLENDON ........................ Secretary of State HoN. W. J. SPEER .. . ...... . ............. . ..... State Treasurer HoN. W. A. WRIGHT .. . ................... Comptroller-General HoN. CLIFFORD WALKER . ............ ; .... Attorney-General HoN. J. J. BROWN .. . ..... .. .. .. ... Commissioner of Agriculture RoN. M. L. BRITTAIN . .. .. ...... Commissioner of Public Schools
iii
LETTER OF TRANSMITTAL
GEoLOGICAL SuRVEY OF GEORGIA,
ATLANTA, NOVEMBER 3, 1919. To His Excellency, HuGH M. DORSEY, Governor, and President of the
Advis01:y Board of the Geological Survey of Georgia. Sm: I have the honor to transmit herewith for publication the report of J. P. D: Hull and L. P. Teas, Assistant State Geologists, on the Oil Prospect near Scotland, Telfair County, Georgia.
Very respectfully, S. W. McCALLIE, State Geologist.
TABLE OF CONTENTS
INTRODUCTION
7-9
GENERAL STATEMENT . . . ... ' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1t
LoCATION .............................................. . ... . 1112
ToPOG&APHY ................................... .... 12-J 3
GEOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. 13-15
DESCRIPTION OF SEEP ........................... ... . ]5-18
PHENOMENA OF SEEPAGE .............. . 1 21
GENERAL CONDITIONS FAVORABLE FOR COMMERCIAL OIL ACCUMULATION . .... 21 22
APPLICATION OF CONDITION IN THE SCOTLAND AREA ... , ........... . .. 2:.-23 Souree ........................................................ 22-23 Containing medium and cover.................... . .......... ...... 23 Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
EviDENCE OF THE SANDSTONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ . .... S3-26 Indurated clay and sand .................................. .... , .. 25-26 Conglomerate ................................ : . . . . . . . . . . . . . . . . . 26
ARTESIAN WELL EVIDENCE .................................. , . , , , .. 27-32
DIRECTION OF STREAMS ......... , ... , ..... , ...... , ... ... , . , 32
CoNCLUSIONs ........................................... . 32-33
T
INTRODUCTORY
In presenting to the public the following report on the oil seepage in the vicinity of Scotland, Telfair Dounty, by J. P . D. Hull and L. P. Teas, Assistant State Geologists, I feel it will not be out of place to give a short resume of oil prospecting in Georgia.
The first serious attempt so far as known to this department, made to prospect for oil in Georgia was that of Capt. A. F. Lucas, the discoverer of oil at Beaumont, Texas. Operations were begun by Lucas in 1905 on what was then known as the Black farm situated in Jefferson County, 3% miles southwest of Louisville. The undertaking was based mainly on what appeared to be a well defined seep of crude petroleum occurring in a small spring. Lucas extended the test well to a depth of about 500 feet where quicksand was encountered which could not be penetrated by the drilling outfit in use and the well was abandoned.
Some two years following the abandonment of the well by Lucas, the Georgia Petroleum Oil Company took the well in charge and continued it to a depth of 1143 feeP where crystalline rock was encountered and the undertaking was then permanently abandoned. The sinking of this well demonstrated two very important facts, namely, the thickness of the Tertiary and Cretaceous rocks in that section of the State, and the absence of commercial oil in the immediate region.
Only a few month$ after the Lucas well was begun a test well for oil and gas was sunk in Wayne County about one mile southwest of Doctortown by a company organized in Savannah. This well was discontinued at a depth of 1901 feet after an expenditure of between $15,000 and $20,000.2 Mr. C. A. Gilson, the contractor for
1 McCallie, S. W ., Preliminary report on the underground waters of Georgia: Geol. Survey of Ga. Bull. 15, pp. 128-131, 1908.
McCallie, S. W., op. cit., pp. 190-192.
Tii
this well, reported a limited amount of gas at two or more points below the 500-foot level, hut its chemical nature seems not to have been definitely determined.
The most extensive undertaking in the way of deep oil well prospecting in the State was that of the Waycross Oil &Gas Company. This company began sinking a deep well during the early part of 1915 on leased lands in the vicinity of Fredell on the Waycross & Southern Railroad about 10 miles south of Waycross. This well was abandoned March, J918, at a depth of 3040 feet after the expenditure of about $60,000. It is claimed that evidence of oil was encountered between 700 and 1000 feet. Salt water was struck at about 2000 feet and at several points below that depth.
Subsequent to the date of the beginning of the oil well test by the Waycross Oil & Gas Company there was considerable interest manifested in oil possibilities along Chattahoochee and Withlacoochee rivers in the southern part of the State. This activity was in a large measure due to a reference in the Report on the Geology of the Coastal Plain of Georgia to the hypothetical anticlines mapped as occurring on these two rivers, this supposition being based on the direction of the tributary streams and other data.' On the possibility that these anticlines actually existed large areas of land were leased along these two streams by the Standard Oil Company and local companies. None of these companies so far have made any effort to put down test wells except the Fitzgerald-Pennsylvania Oil & Gas Company. This company sunk a well to the depth of a few hundred feet but as far as known no indication of oil was found .
In view of the fact that the above mentioned activities were due in a large measure to the supposed anticlines ex-isting along Chattahooche and Withlacoochee l'ivers and that considerable money was likely to be spent in prospecting along the rivers it was thought advisable to investigate these supposed anticlinal structures more thoroughly. Accordingly the matter was taken up with Dr. George
1 Veatch , O tto , und S t eph e n son, L loyd vV illium , Prelim inary rep ort on t he Geology of tl1e Coastal Plain of Ge orgia: Geol. Survey of Ga. Bull. 26, pp . 62 - fiil, 1911.
viii
,.
Otis Smith, Director of the U. S. Geological Survey, and he was asked to cooperate with the State Survey in securing more definite data as to these anticlines.
Dr. Smith readily consented to cooperate in this investigation and in May 1917 detailed three geologists for the work. The two assistant State Geologists joined the Federal geologists at Columbus. May 8th, and the exploration of the Chattahoochee river and contiguous country was immediately begun. Two of the party descended the Chattahoochee River in a boat while the others examined the surrounding country adjacent to the stream. The rate of progress down stream was so arranged that the geologists in the boat and those investigating on land could often meet to compare notes. The work along the Chattahoochee progressed satisfactorily and was completed May 28th. In like manner the so-called Withlacoochee anticline was investigated and the field work was completed June 12th.
At my suggestion the U. S. Geological Survey published July 31, 1917, in Press Bulletin No. 327 an article setting forth the object of the cooperative work and the result obtained. "It is not possible at this time," the article states, "to describe in detail the structure of the area considered; it may be stated, however, that the evidence of the existence of anticlinal folds is unsatisfactory and inadequate and affords no sufficient ground for drilling for oil.''
In addition to the oil prospects, above referred to, it may be well to call attention to the recent activities of the Middle Georgia Oil & Gas Company. This company contemplates putting down a well for oil near the northern margin. of the Cretaceous formation in Washington County, 12 miles northwest of Sandersville. The Jakin Oil & Gas Company also is considering the question of putting down a test well near Jakin in the northwestern part of Decatur County.
S. W. McCALLIE, State Geologist.
ix
OIL PROSPECT NEAR SCOTLAND, TELFAIR
COUNTY, GEORGIA
BY
J. P. D. HuLL AND L. P. TEAs, Assistant State Geologists.
General Statement.-The discovery of the oil seepage that caused the geological investigation on which this report is based was made in the summer of 1919 by H. G. Sample on his farm about one mile south of Scotland, Telfair County. It is said that former owners of the farm had frequently noticed unusual scums on the surface of the water in poorly-drained areas and that the cattle sometimes refused to drink from the spring at the edge of the small swamp, but it was not until Sample bought the land about a year ago that the presence of oil was seriously suggested. In September he collected samples of the oily accumulation. An analysis was made by Dr. Edgar Everhart, acting chemist of the Geological Survey of Georgia arrd a few weeks later, S. W. McCallie, State Geologist, made a preliminary examination of the property. In October the writers were instructed to make a geological study of the area for the purpose of determining the presence or absence of conditions favorable for a commercial quantity of oil. They spent two weeks in field work covering an area of approximately one hundred square miles in Telfair and Wheeler counties. Their efforts were concentrated on the geological structure underlying the area surrounding the seeps.
Location.-Scotland (population, 1910, 271) is a station on the Southern Railway 83 miles southeast of Macon and 104 miles north-
2
GEOLOGICAL SURVEY OF GEORGIA
west of Brunswick. It is on Little Ocmulgee River 5 miles southeast of McRae the county seat of Telfair and 7 miles south of Alamo the county seat of Wheeler. The river forms the boundary between the two counties.
Topography.-The area surrounding Scotland, comprising Telfair and Wheeler counties, lies in the central part of the Coastal Plain division of Georgia and is also in the center of the physiographic subdivision known as the Altamaha Upland. The Upland is the largest of the Coastal Plain divisions. It extends from Savannah River on the north to Florida on the south. It is bordered on the north and west by the Fall Line hills and the Dougherty plain and on the east it grades into the lower Okefenokee plain. Its elevation above sea level ranges from 125 to 470 feet.
The Scotland area which is discussed in this report lies partly in Telfair and partly in Wheeler counties, between Oconee River on the northeast and east and Ocmulgee River on the southwest and south. These rivers unite a:bout 15 miles east-southeast of Scotland forming the Altamaha which is one of the principal drainage systems of the Coastal Plain. The area is traversed from northwest to southeast by Little Ocmulgee River (Gum Swamp Creek) which joins the Ocmulgee at Lumber City, 12 miles southeast of Scotland.
The topography is characterized by gently rolling hills that are generally not higher than 50 or 60 feet a"tove stream level. The surface of the plain slopes southeastward at a rate not less than 4 feet per mile. Streams flow sluggishly southeastward in meandering courses through broad shallow valleys. The maximum relief of the area is probably less than 150 feet. Each of the three rivers, Oconee, Little Ocmulgee, and Ocmulgee, is bordered in places by distinct terrace plains, one 10 to 20 and the other 40 to 50 feet above low-water leveL Northeast of Little Ocmulgee River is a belt of sand hills in places 1% miles wide and as high as 50 to 75 feet above stream level.
The known altitudes above sea level at railroad stations are as follows:
OIL PROSPECT NEAR SCOTLAND
'3
Station
Authority
Elevation
McRae Scotland Towns Lumber City
U. S. Geological Survey
229
U. S. Geologi~al Survey
14?
U. S. Geological Survey
128
U. S. Geological Survey
146
The soil is generally sandy. Wire grass is a characte_ristic type of vegetation. The area was once covered with long leaf pine forests that have been only partly replaced by younger growths consisting principally of pine, oak, and gum. Cypress swamps are common.
Geology.-Aside from the Pleistocene terrace deposits occupying narrow strips along Oconee, Little Ocmulgee and Ocmulgee rivers, and exposures of sandstone and quartzite of the Alum Bluff formation (Oligocene) along the same streams, the surficial geology of the Scotland area may be described as unconsolidated sands and sandy clays locally indurated and ferruginous that h~ve been variously designated as belonging to the Altamaha (Lafayette) formation of the Pliocene ( ?)1 but have most recently been considered Oligocene and probably contemporaneous with part of the Alum Bluff formation. 2
The following paragraph on the geology of the area is condensed from a description of the geology of Montgomery (now in part Wheeler ) and Telfair counties by Stephenson and Veatch :3
The surface deposits throughout the interstream areas consist of 100 feet or less of irregularly bedded sandy clays and sands with subordinate interbedded layers of argillaceous sandstone. They are underlain by 100 feet or more of soft sandy clays and sands, in part water bearing, with interbedded thin layers of sandstone and quartz-
1 Jfor description and discussion of Altamaba rorma.tl on, se e Veatch, Otto, and Stephenson, Lloyd William, Prelimlnary r eport on the Geology of the Coastal Plain of Georgia, Geol. Survey o! Ga. Bull. 26. pp, 401-423, 1911.
Stephenson, L . W .. and V eatch . J . 0 ., Underground waters of the Coastal Plain o.f Georgia, U. S. G. S. Water Supply Paper 341, pp. 94-97, 1915.
Op. cit., pp. 345 and 411-412, 1915.
Table of Geological Formations in the Coastal Plain of Georgia
..
System Quarternary
Series Recent Pleistocene
Pliocene
' Miocene
Tertiary
Oligocene
Eocene
Cretaceous Pre-Cambrian
Upper Lower
Group
Formation
Columbia
.
Appalachicola Claiborne
Satilla Okefenokee Altamaha (Lafayette?) Charlton Duplin marl Marks Head marl Alum Bluff Chattahoochee Vicksburg Jackson Barnwell McBean Wilcox Midway Rip ley Eutaw Not differentiated
Thickness in feet
Remarks
10-50
5-40
~
150 (max_)
I
~
? 10-15
Probably absent in Scotland Section
0
2
~
1:-i 45
~
150 (aver.) 150
-
~
~
300
Referable to Jackson
0
150
"":!
100
~ ~
100-400 (max.)
2
150 (max.)
~
400
'
950 (approx.)
560
350-600
OIL PROSPEC1' NEAR SCOTLAND
5
ite that belong to the Alum Bluff formation. The Alum Bluff formation is underlain by 500 feet or more of limestone with interbedded layers of calcareous sandstone and marl, which proba:bly represent in descending order the Chattahoochee and Vicksburg formations of the Oligocene and perhaps the Jackson formation of the Eocene. These formations contain water-bearing beds. Beneath the limestones in descending order are a series of sediments of Eocene and Cretaceous age which probably have an aggregate thickness of 1,500 l':let or more and which rest upon a basement of ancient crystalline rocks. These deposits contain. important water-bearing beds.
The general dip of the deposits is southeastward, increasing with the age of the deposi.t from 4 or 5 feet to about 30 feet per mile. The general stratigraphic relations of the formations are shown in fig. 1, which is taken in part from Stephenson.1
The table on the opposite page shows the geological formations in the Coastal Plain of Georg1a, \Jut several of the formations are absent in the Scotland section and the presence and thickness of the older and lower beds are uncertain: The table which is taken with some modifications from Veatch and Stephenson2 is only an approximate guide for this section.
The Seep.-The oil seepage occurs on H. G. Sample's farm somewhat less than a mile south of Scotland. Local topographic and cultural relations are given on map No. 2. Sample's house is on lot 303, 15th district, 0.8 mile south of Scotland. The springs on which the oil accumulates are in cleared but swampy ground at the head of a small drainage ravine approximately 100 yards west of the ScotlandJacksonville (Ga.) road and about 500 feet southwest of the house. Local relief is low, the spr.ings being only 10 to 15 feet higher than the road and at about the same level as the house. Cultivated fields lie north and west of the swampy area and 10 to 20 feet higher. A
1 Op. cit., opp. p. 122, 1916. 2 Veatch, Otto, and Stephenson, Lloyd William, Preliminary report on the Geology of the Coastal Plain of Georgia: Geol. Survey of Ga. Bull. 26, pp. 60-61, 1911.
NW ',
st. 0
t
J ~
.~
j "
l,!'
'll
~
::.........
~llP'O" ~rT~ te bonto,..tl s:cle
o
tO
l?
~ Miles
Fig. 1. GeologiQ section from point near Macon southeast through Scotland.After L. W. Stephenson, U. S. Geological Survey.
OIL PROSPECT NEAR SCOTLAND
7
pine thicket occupies the head of the drainage ravine at the south, and recently drained untilled land extends eastward to the public road. The area of the seepage itself covers less than an acre and is about 200 feet above sea level or 50 feet higher than the depot at Scotland. Although this is the only place on the farm where oil has been found Sample reports that a similar scum was once noticed a few hundred yards farther northeast down the. ravine on the east side of the road. This locality, however, was found to be dry.
There are four principal pools, or springs, at the seep, numbered for convenience of reference 1, 2, 3, and 4 (See map 2). In addition No. 5 is an artificial excavation, or pit, at the head of a ditch leading northeast to the road. All pools are in wet swampy ground.
No. 1 nearest the house, is the original spring about 3 feet in diameter and a foot or more deep including mud in the bottom. This is the spring from which the cattle sometimes refused to drink. It has been somewhat enlarged and enclosed by a fence.
No. 2 is a shallow natural pool 55 feet south of No. 1. It is about 4 feet long and 2 feet wide. No oily scum has been noticed on its surface, though vari-colored iron oxide films are usually present.
Nos. 3 and 4 are similar shallow pools or springs 70 feet and 90 feet respectively farther south. They are at the same elevation as Nos. 1 and 2 and have similar wet, mucky, grassy edges. Irridescent oily films occur on both pools. Two samples, one collected by Sample in September and one collected by the writers in October, were analyzed by Dr. Edgar Everhart, acting chemist of the State Geological Survey.
No. 5 is a pit a:bout 3 feet square and 6 feet deep dug in the less m-:>ist sandy clay at the head of a drainage ditch near the pine thicket 170 feet east of No. 4. The material exposed is gray and rusty yellow sand and sandy clay, becoming firm and compact with depth. No water was encountered in the excavation, but a little
8
GEOLOGICAL SURVEY OF .GEORGIA
seeped into a shallower (3-foot) pit dug 3 feet away on the opposite side of a small pine tree. Distinct films of oil appeared on the water and a strong odor like kerosene and sometimes like turpentine came from the sandy clay. The odor was still strong and easily detected. within a few feet of the hole, even after the soil had been exposed two weeks to air and rain.
Observations were not confined to the main springs but about 25 small holes were dug 3 to 4 feet deep with a post-hole digger. These
test holes generally penetrated 1 to llh feet of porous gray sand mixed
with dark loam and vegetable matter overlying compact rusty yellow, pink, and gray sandy clay. All holes filled with water within an hour or less after 'being dug, except two or three near pit No. 5. The majority of the holes showed oil within an hour or two and some almost immediately after being dug. Those that did not show oil and gave no indication of it more than a week after being dug are marked by a minus sign (-) on map No. 2. One is 2 feet west of No. 3 and three others are between Nos. 3 and 5. The holes in which oil appeared are mar ked pl us (+) . In a and b, dug Oct. 7, 2 feet from No. 3, oil films appeared the same day; in c and d, dug Oct. 9, 15 feet from
No. 3, faint films appeared within a few hours; in e .and f, dug Oct. 15,
30 feet from No. :3, films appeared within an hour; and in g, also dug Oct. 15, 25 feet west of No. 3, a :film and a distinct kerosene odor were noticed immediately. In most of the other holes, oil was also detected by films and odor either while being watched or on the following day. No particular significance is attached to these results, except as they show that the oil does not occur at all places in the swampy area and that there are barren spots between oily seeps, all of which might be expected in the area of a seep as the substratum is in places more porous than in others, thus allowing the oil as well as water to pass through more readily.
The Seepage.-The peculiar phenomena noticed at the seep are oil films and gas bubbles. Oil films are common at all seeps except No. 2. They are readily distinguished from the rainbow-like iron
OIL PROSPECT NEAR SCOTLAND
oxide films which they resemble in color by their peculiar continuity or resistance to separation or division. If a straw, for instance, be drawn through an iron oxide film, the surface is broken up and separated by cracks of open water, but if an oil film is thus .disturbed, it does not part but closes in immediately after the straw is removed. The oil film is also recognized by its odor.
0
35
10
Scol ~ In Feet
I
Contovr Intervol sFt
N
s
..0....
Area
2. ... ...
..... of Seeps
3 ... ....
.. - .... .... .!
Map 2. Sketch map of oil seeps on property of H. G. Sample, Scotland, Telfair County. Explanatien : Circles=springs or seeps; small letters= post boles referred to in text; ,plus signs=post holes showing oil; minus signs=holes showing no oil.
Two types of oil films were detected. The most common appearance was that of a minutely tenuous film spreading over the surface of the water. It was either light gray or beautifuUy irridescent, depending probably upon the degree of cloudiness or the angl-e from
10
GEOLOGICAL SURVEY OF GEORGIA
which viewed. The odor, not always readily detected when the film was minutely thin, was that of kerosene.
The other type of fihp_ was heavier in appearance, thicker, and dark brown in color. When skimmed with a spoon from the water surface near the gvass roots at the edge of the pool where it seemed more a:bundant, the oil followed the water into the bowl of the spoon and was then forced by the inflowing water to the rim of the spoon forming a dark oily border. This type possessed a rich nut-like odor, resembling crude petroleum. When collected in spoon and bottle it leaves small brown clots on slightly roughened surfaces. The two types probably had the same source, the one being an extremely thin film or a naturally refined product of the other. When absorbed by a flannel cloth laid on the water and ignited by a match, the oil ; sputtered and burned, producing a black smoke.
The quality of oil from the Sample farm (not over one pint has so far been collected) is shown in the following analysis made by Dr. Edgar Everhart, acting chemist of the State Geological Survey.
"Analysis of oil from farm of H. G. Sample, Scotland
Specific gravity at 150 Distilled to 1500 (302F) Distilled to 150-2000 (302-3921<,) Distilled to 200-2500 (392-482F) Distilled to 250-3000 (482-572F) Distilled to 300-325 C (572-617)' Residue above 3250 (617F)
0.8485 1.4% 3.0% 20.0% 43.0% 15.0% 17.1%
Above 3000 (572F) the oil decomposes a good deal, therefore distillation was stopped at 3250 (617F). The residue in the retort was a viscid liquid and gave the reaction for asphalt.
The oil resembles some of the California petroleums.'' Gas bubbles rose from all of the pools, irrespective of the presence of oil films. No regularity in time of bubbling and size of bubbles
OIL PROSPECT NE.AB SCOTLAND
11
was noticed. Bubbles rose when the water was quiet and undisturbed as well as when the pool was stirred with a stick, although in the latter instance the bubbles were larger and more numerous. When the water was not agitated, 4 to 10 bubbles ranging from
l4 to % inch in diameter were counted per minute. On some days
no bubbles were noticed during the visit. When the bottom of the pool was vigorously stirred, the surface of the water was frequently covered with bubbles ranging in diameter from a fraction of an inch to more than an inch. A burning match held over the surface while the bubbles rose, caused the gas within the bubbles to pop faintly but distinctly and to burn with a flame somewhat less colored than the match flame. One flame was noticed about 2 inches wide and 2 inches high, caused by several bubbles in a row igniting at once. As the writers were not able to collect the gas in a quantity sufficient to analyze, its chemical composition is unknown.
GENERAL CONDITIONS FAVORABLE FOR COMMERCIAL
OIL ACCUMULATION
It is very seldom that conditions indicating commercial"oil bodies are shown by surface phenomena, consequently not too much confidence should be placed in dome-like hills, black soils, or even oil seeps.
Oil is generally believed to be the product of the decomposition of animal and vegetable matter buried deeply beneath the surface. Accompanying water forces the small oil globules out of the denser rocks where they originate into the porous sands where they slowly move _up the slope of the rocks until they meet with a natural trap where the oil collects to form large pools of commercial value.
These natural traps are called anticlines, or domes, and are pr().. duced by forces which fold or wrinkle the underlying layers of rocks just as a piece of paper may be wrinkled by lateral pressure. These wrinkles will of course extend usually to the surface through the
GEOLOGICAL SURVEY Ob' GEORGIA
rock layers although they generally imprison the oil and gas several hundreds and often thousands of feet beneath the surface.
It is necessary that the rock just above that containing the oil and water be impervious so that the oil will not escape upward. The oil, being lighter than water, will collect in the upper part of the dome, beneath the gas, and above the water.
The presence of favorable underground structure can often be determined from the surface rocks. The elevations above sea level of the same layer are determined over the area to be mapped and from them the structure, or position of anticlines, if present, is determined.
Often, however, it is impossible to find a layer or layers that can be distinguished and correlated within an area. Sandstones, due to their lens-shap.ed character and irregularities are poor key horizons, or layers, upon which to base structure. Limestones are much more continuous and more uniformly bedded, hence they are generally used, if they can be found.
The presence of surface oil springs, or seeps, shows that there may be oil far below the surface, which cracks in the intervening rocks allow to escape.
From the foregoing, it is evident that the following conditions are necessary for the accumulation of oil in commercial quantity:
1. A source. 2. A containing medium. 3. An impervious cover. 4. Structure (Natural traps, domes, etc.).
APPLICATION OF CONDITIONS TO THE SCOTLAND AREA
1. .A. source.-Examination of the underlying rocks where they come to the surface 75 miles more or less to the north of ~cotland shows them to be largely marine in origin, with entombed remnants of plant and animal life capable of producing oil. These rocks belong to the Cretaceous system which is oil bearing in Louisiana and Texas.
OIL PROSPECT NEA.R SCOTLAND
13
. 2.-3. Containing medium and impervious cover.-An examination of the area east from Columbus to Augusta shows numerous beds of sand capped by impervious layers of clay. The natut"al dip of the rocks from Macon would put these rocks from 2000 feet to 3000 feet be~eath the surface at Scotland. Numerous artesian wells point to the fact that these conditions are ;tlso satisfied nearer the surface.
4. Structure.-In attempting to work out the structure of the Scotland area it was necessary to consider the surface exposures of sandstone and clay and also the surface of the underlying limestone as shown by the records of artesian wells in the vicinity.
EVIDENCE OF THE SANDSTONE
The only surface stratum in the Scotland area that seems to possess any value whatever as a key horizon in determining geological structure is the sandstone (Oligocene ?) frequently exposed in railroad cuts, encountered in dug wells, and outcropping in road cuts and along stream channels. 'rhis sandstone may be described as somewhat friable, gray in color, fine to medium grained, and in places near its base conglomeratic in texture. One peculiarity is its light gray to almost white opaline cement which holds together the somewhat subangular quartz grains. Small flakes of muscovite are present but not at all plentiful. It was with some reluctance that a sandstone, devoid of fossils, lens-like, and differing in thickness from place to place, was selected as a basis for structural work. It was soon found that the sandstone was not trustworthy as a key rock because at most places it was not known on which of several beds of sandstone occurring within a depth of 60 feet the elevation was being taken. Even assuming that the sandstones observed in the area and plotted on map No. 1 represent the same horizon, they are not sufficiently numerous to warrant the drawing of reliable structure contours.
14
GEOLOGICAL SURVEY OF GEORGIA
Sandstone beds occur most abundantly, as observed in a few exposures and in dug wells, in three small areas in Telfair County, namely, (1) along the. Jaybird road 3 niiles northwest of Helena, (2) along the Milan road 3 miles southwest of McRae and (3) at Scotland. In Wheeler County they are found along the Dublin road 4 miles northeast of Alamo and along Alligator Creek 3 miles north of Avants Siding. Reference to Map No. 1 w~ll show that there is little structural value in the elevations 1\nd distributions of these
J '
(.::)~ ~.currences, except as they indicate the presence of several horizons of rock that appear to be lithologically the same but are stratigraphically different.
The apparent lens-like character of the sandstone is shown in the Southern Railway cut west of Scotland near whose west end the 2-foot sandstone bed disappears by pinching out or by grading into semi-indurated sandy clay and unconsolidated rusty yellow sand.
An illustration of the several confusing horizons appears in the
dug well at Mrs. O'Neil's house about % mile south of Scotland. A
vertical section of this well as given by Mrs. 0 'Neil follows:
Section of 111rs. O'Neil's well
Soft clay. . . . . . . . . . . . . . . . . . . . . 0-10 feet White sandstone ... . .......... 10-18 feet Clay ........... ............. 18-22 feet Sandstone ...... ....... ...... 22-24 feet Clay ............. .. . ........ 24-26 feet Sandstone ..... .............. 26-35 feet
Since it appears that several sandstone beds occur, that the beds are lens-like and non-continuous, and that the beds, even if they should represent separate and definite horizons, are lithologically similar and only uncertainly distinguished where found in isolated occurrences, it is questionable whether any reliance can be placed on structure determined with the sandstone as a key horizon.
OIL PROSPECT NEAR SCOTLAND
15
A generalized vertical section of the stratigraphy observed extending from the bridge over Little Ocmulgee River at Scotland to a point on the Jacksonville (Ga.) road about 1:14 miles south of Scotland is here given.
Vertical section at Scotland, Telfair County
Units
Thickness in feet
!Elevation in feet of top of unite above sea level
1. Surface. Rusty yellow sandy loam with ferru -
ginous pellets .....' . ..... . ...... . .. . ...... . . .
2.5
2. Gray sandstone, medium grained . .. . .. .. .. . .. . . .
4
.3. Same as (1) with mottled rusty yellow and
gray sandy clay and sand.......... . .. . ... . .
16
4. Gray sandstone . .. . . . ... . .. . . . .... .. .. .. .... . .
8
.5. Clay . .. . .................................. .
4
6. Gray sandstone with thin clay layers .. . ....... . .
12
7. Sandy clay, mottled and variegated . . .. .. .. ... . . .
19
:8. Gray sandstone in river bed .......... . ... .. . .. .
15
195.5 193
189 173 165 161 149 130
No evidence was found that these sandstones continue northward into Wheeler County.
The geological section showing relative elevations and positions -of the sandstone beds from Little Ocmulgee River southward along the Scotland-Jacksonville (Ga.) road is graphically shown in figure 2.
A casual glance at fig. 2 suggests a rising dip of sandstone southward, but in view of the known irregularity and non-persistence of ihe beds in the Scotland area, the conclusion that the same bed rises toward the south is questionable. It seems probable that sandstone beds or lenses that might have been correlated with the beds at the south end of the section have been eroded at the north end by Little ,Ocmulgee River.
Indurated clay and sand.-A number of prominent exposures of indurated clay and sand occur along Alligator Creek in Wheeler County and at scattered points throughout the Scotland area, par.. ticularly to the north. This material frequently forms continuous ledges with cliff-like faces 6 to 10 feet high. In places the outcrop
16
GEOLOGICAL SURVEY OF GEORGIA
...........
"'
Fig. 2. Geological section showing relative positions of sandstone beds at Scotland, Telfair County. Horizontal scale in miles. Elevations given above sea level.
covers several acres. Layers of gray sandstone occur in the clay. Elevations of this clay may vary only slightly in the same region. VariationS of 50 feet however over distances of a mile or two show that another indurated horizon must occur or else it is very thick. It was found to be unsatisfactory as a key bed, but the fact that in several localities elevations taken along a line of outcrop togethe'r with well data over a distance of a mile showed slight variations, might indicate that anticlinal structure is not present.
Conglomerate.-Near the Alamo-Dublin road 4 miles northeast of Alamo in Wheeler county a number of cliff-like exposures of sandstone with a basal conglomerate occur. They show a ledge of sandstone 10 feet thick. Elevations along this ledge for about a mile showed a slightly irregular south dip. This bed appears to be better developed still further north but little evidence of it occurs to the south. It appears on the south side of Alligator Creek 6 miles south of the Dublin road exposures and about 20 feet lower.
ARTESIAN WELL EVIDENCE1
Throughout this section a number of artesian wells have been drilled varying in depth from 150 to 425 feet. The flow of water is
~ The following persons have drilled most ot the artesian wells in the Scotland area: J. F. Wooten, Eastman, Ga., Robt. Murray, Lumber City, Ga., Carter & Vaughan, Lumber Cit y, Ga., E. Jones, West Point, Mississippi, J. C. Thornberg. Glenwood, Ga.
OIL PROSPECT NEAR SCOTLAND
17
usually derived from cavities in the Chattahoochee and Jackson limestone. 2
Before reaching the limestone these wells penetrate alternating beds of clay and sand, the latter sometimes indurated. The clay varies in thickness considerably exceeding that of the sand. Shellbearing strata are usually encountered just above the water bearing limestone though in places they are found 60 to 100 feet above this horizon.
In view of the lenticularity of the sandstones in the Scotland area it is believed that structure based on reliable well data would be much more dependable than that based on surface exposure data. Reliable well records, however, are extremely difficult to secure for a numbel' of reasons. The method of drilling employed does not readily permit a distinction to be made between soft limestones and partially indurated clays even were the drillers anxious to secure such a separation. What might be considered the top of the Chattahoochee limestone in a well record may actually be below it. If we attempt to base structure on the depth of the water bearing bed we are confronted with the probability that these beds are likely to be extremely irregular occurring as they often do in cavernous limestone.
In the accompanying map (No. 1) the top of the limestone (probably Chattahoochee) is indicated in figures at the well site. The top of the Chattahoochee limestone is supposed to be the top of the rock from which a strong flow of water is obtained, or the top of the rock lying just above the water if the flow came from soft material. This method of course is open to the objections that the top of the limestone in places may have been soft, and also that the hard rock above the water flow may have been a sandstone with the limestone some distance below.
Figures 3 and 4 show two sections taken at right angles across the Scotland area. From these the surface of the Chattahoochee
"I,The Vicksburg limestone lying between the Chattahoochee and the Jackson limestones in the geologic column has recently been found to be largely Jackson in age. See Cooke, Charles Wythe, and Shearer, Harold Kurtz, Deposits of Claiborne and Jackson age in Georgia: U. S. Geol. Survey, pp. 120-C, 1918.
18
GEOLOGICAL SURVEY OF GEORGIA
limestone appears to be rather irregular in view of its conformity with the Alum Bluff above. In the Alamo-Scotland section (fig. 4) the maximum relief is 31 feet in 6 miles and in the Helena-Lumber City section (fig. 3) 178 feet in 17 miles. In the latter section the maximum relief around Scotland is 46 feet in 4 miles. This relief if uniform, would not be unduly large, but its irregularities suggest errors in determining the top of the Chattahoochee limestone. Its significance as an index of structure is not believed to be important. However, opinions are likely to differ in such a matter.
NW
~
z ....
..... < ~ ~
0 z
<
...J
t-
_,._.,o J.LWillcox8
I ~ o-', ',,
Cl)
---:X---~
~~ 12.~:10 l"'ognolio
"'Y:'-Jb
Shom rock Spr
Seu
</)
z
5
0
t-
level
,x-10 J. R.Lo n c ~ster ' ' \
SE
0: u.J
co :E::>-
;:,1-
...J'u
1"\.l./"\c Roe
)C -55
, ' '\
.....x':73 \
1"1 l.l"'' Rae\
I
' '
"/09
E.H.Elaer \
' I
I I
-lb2 ~
City
Fig. 3. Section from Helena to Lumber City showing top of Chattahoochee Iime-
s>ne in artesian wells. Horizontal scale, 1 inch=2 miles. Vertical scale, 1 inch= 40 feet.
It is admitted that the evidence of the deep wells taken in combination with the surface sandstone data affords a possibly favorable interpretation of the local structure at Scotland, but in view of the irregular structure of the whole area and the inadequate data already discussed, the writers place little confidence in its value as indicating "oil structure." The suggestive evidence, however, is here given. It
UlL PROSPECT NEAR SCOTLAND
]9
is seen from fig. 2 that the uppermost sandstone observed south of
Little Ocmulgee River, if assumed to represent the same horizon,
shows the beds dipping northward beneath Little Ocmulgee. As no
corresponding sandstones are, known to outcrop within the area a few
miles north from the river, it may be assumed that the beds continue
to dip northward beneath the surface in Wheeler County. In sup-
port of this assumption, it may be observed that the low peak of the
supposed Chattahoochee limestone at Scotland (fig. 3) is accentuated
by the steep northward dip of the same horizon from Scotland to the
Bonner farm (see fig. 4). The apparently abnormal southward rise
of the limestone and the corresponding 11.nd assumed southward rise
of the sandstone might th-qs be interpreted as suggesting anticlinal
structure, but only suggesting it.
Another way of determining the structure is suggested by the
shell beds encountered above the water-bearing horizons. So few
well records, however, mention the point at which these fossil shells
first appeared that but little reliance could be based on them in
determining structure.
0
<::>
z::
<:
N ~
S-'.s
o - -"C: - - -Se-, -te-..,e-t - - - - - V)
10
~- .: C1t~
/ l ' J,T. Elder
iO
lit..-~-
,
Pcto n Fora' - - -1l'
Bou e
er
In the following table of artesian well data, the third column shows the probable depth in feet to the Chattahoochee limestone; the fourth column shows the datum used for determin-
Verti,ol soole in feet
Sc<>le in miles
Fig. 4. Section from Alamo to Scotland show-
ing top of Chattahoochee limestone in artesian
wells.
,
ing structure, datum being elevation of the top of the limestone with reference to
sea level; the fifth column shows the static head or the height to
which the water will rise above the horizon where the flow is obtain-
ed; the sixth column shows the surface elevation of the well above
sea leveL
-
--
Owner
Artesian well data in Scotland area
Location
Depth to limestone
Datum
Static H ead
Elev.
"0 "
Authority
J. T. Wilbanks
Lumber City
308
- 162
158
146
Carter & Vaughan
(good)
E. H. Elder
Lumber City
280
- 109
157
171
Robt. Murray
(Doster)
Lot 332 ?
Lumber City
(good)
~
~
Max L. McRae
Lumber City, - Lot 274
281
-55
222?
226
Robt. Murray
(good)
0 t-< 0
Max L. McRae Towns, Ga.
Peachview farm
Towns, Lot 291 (?) 7th district
293
. -73
141
220
Robt. Murray
(good)
Towns
175
-47
150
128
J . F. Wooten
~
~
t-<
(oral)
l:io
Towns Hotel
Towns
Eastman, Ga.
128
J. F. Wooten
<:::j ~
-.:::
(oral)
~
J. A. Ramsay
Towns
148
128
J. F. Wooten
"<
(oral)
0
J. R. Lancaster
Lot 310, 7th dist.
165
- 10
155
J. F. Wooten
""1
L. J. Clegg
1 mi. west of Towns
1% mi. E. Scotland
180
-30
Lot 309
(oral)
'<'l
150
J . F. Wooten
~
(oral)
0
~
Scotland, Ga.
Scotland
166
- 21
171
145
J. F. Wooten
(oral)
~
J. T. Elder
Scotland, Lot 226
180
-25
160
155
J. F. Wooten
(oral)
? McRae, old
Scotland
Turpentine still
McRae
287
142
J. F. Wooten
171
(oral)
241
W. S. Jessop
McRae, new
McRne
179
200
W. S. Jessop
Empire Cot. Oil Co.
McRae
202
-12
190
J. F. Wooten
(oral)
A1tesian well data in Scotland (Continued)
Owner
Location
Depth to limestone
Datum
Static Head
I Elev.
Authority
Old Cotton Oil Mill
McRae
?
174
180
J. F. Wooten?
,
L. L. Campbell
McRae, Lot 203 ?
128
27
155
Robt. Murray
(good)
Shamrock Springs
McRae, Lot 217 ?
140
-16?
167
155
J. F. Wooten
(good)
Magnolia Well
McRae, Lot 218
155
0
170
155
Robt. Murray
(good)
0
~
J. L. Willcox
Helena, Ga., No. 1 Helena, Ga., No. 2 Coca-Cola Bot. Co. Redman gin
E. of McRae, Lot 231, Gum Swamp Helena Helena Helena Helena
144
270': 250?
16
187
17?
184
- 6?
182
192
160
Robt. Murray
(good)
247
H. E. Hosmer
267
H. F. Thaxton
244
H. F. Thaxton
242
J. C. Beatty
;;J
a
VJ
"ll
~
.C...J,
Beatty gin Ice Plant
Helena Helena
250? 280
172
65?
174
242
J. C. Beatty
242
Harry Hosmer
~
ttJ
Long Bridge
N. of Helena, Lot 239, Gum Swamp
175?
98
160?
C. T. Meadows
~
(good)
~
Workmore Farm
Cobbville, Lot 62,
48
260
Robt. Murray
J. T. Williams D. B. Graham
8th district Cobbville, Lot 122, 9th district Scotland
212? 235
28
188
' 263
136
(good)
Robt. Murray (good)
Sam Hughes
Va J
.0...., t-<
~ ~
Mrs. Mollie Clegg
Scotland, Lot 257
no .1s.
149
J. F. Wooten
t:::f
J as. Bonner Farm
Scotland, Lot 284
200?
- 52
158
(oral)
148
J. F. Wooten
Pecan Company
J. Irwin Brown
. Scotland, Lot 349
Avants Siding Towns
250
-38
142
300? 208
-78? -78
132 150
(oral)
212
J. F. Wooten
(oral)
222
F. J. Clark
130
Robt. Murray
(good)
Alamo, Ga.
Alamo
- -- - -
140
209
Robt. Murray
I
(good )
'"'
22
GEOLOGICAL SURVEY OF GEORGIA
Direction of Streams.-It. has been suggested that the at>normal northeastward direction of Ocmulgee River from Barrows Bluff to Lumber City may indicate the pres~nce of an anticline, in Jeff Davis County to the southeast of the river.
No attempt was made during this investigation to determine the actual presence of structure in Jeff Davis. The peculiar direction of the river is rather difficult to explain from purely surface features and it is possible that detailed work will show underground structur8 to be the cause.
CONCLUSIONS1
The data collected during the field work of the Assistant State Geologists seem to establish two facts (1) the presence of a natural oil seepage on the Sample farm and (2) the uncertainty of structure in the Scotland region as shown by field data.
The seepage was under the daily observation of the Survey for about two weeks and special precaution was taken to see that no designing person had an opportunity to salt the pools. Furthermore a large number of holes were put down. and watched until the scum of oil appeared on the surface of the inflowing water. As an additional precaution a second analysis of the oil collected under somewhat different conditions was made some weeks after the first analysis.
It should be borne in mind that while an oil seepage gives conclusive evidence of the presence of oil in a locality where it is found it does not necessarily follow that the oil will be found in commercial quantities. This is well illustrated in the case of the Lucas oil well near Louisville referred to in the introduction of this report. It might be stated however that an oil seepage in a recent formation, as in the Scotland region, is generally looked upon as more favorable than seepages in older formations. At any rate an oil seepage in an
1 Concll,lsions written by S. ViT. McCallie, State Geologist.
,
OIL l'ROSPBCT NEAR SCOTLAND
23
unproved territory is frequently the only surface indication of oil and in some cases it has led to the discovery of important oil pools.
Structural conditions favorable for the accumulation of commercial oil pools in the Scotland district based upon either sandstone or deep well data were not definitely established by field work, however, as pointed out in the text of the report the information secured on both the sandstone and deep well records is suggestive of structure. In case definite anticlinal or domal structure could have been established the chances for finding oil in commercial quantities would be far more favorable than in the finding of the seepage alone. Of all the data than can be secured in au unproved field structure is regarded the most important. It has been st:1ted by one of our most prominent oil geologists that structure alone definitely worked out in unaltered sedimentary rocks, wherever found, is ap1ple justification for expenditure of money in putting down test wells.
In view of the fact that a natural seepage of oil occurs in the vicinity of Scotland together with suggestions of structure I am of the opinion that one or more test wells should be put down in that locality as the drill alone must fin11lly be res<11.-ted to before the area cau be actually proved or disproved. A test well, unless oil should be found at higher elevations, should be extended to crystalline rock which will be encountered possibly at about 3000 feet.
In putting down test wells in the Scotland area,,as in all other unproved areas, it should be fully understood by the citizens of the State that the undertaking is a gamble pure ancl simple with the chances for wimiing small.
MAP 1
]ia 1.
RECONNAISSANCE MAP
oF THE ScoTLAND AREA
GEOLOGICAL DEPARtMENT OF THE STATE OF GEORGIA
EXPLANATION.S
XPOSVRS Of SANDSTON WITH ELEVATIONS A8()Y JEA LEVEl EXPOJVRES OFIIIOVNATED ClAYAND SAND WIT/I ELEVATIONS
*)( 172 190
.fVRFAC WELLS WITH ELEVATioN OF SANDSTON ENCOl/NTER0
D 162
;fRTESIAN WELLS WITH ElEVATION OF .JVPPOJ0 TOP OF ClfATTAHlJIJCH L S. 0 441
Note!. The roods and railroad in Wheeler Coonly o~ 5/refched in rou9hly w/11> re!>pecf to lot 1/nes.
Nofe2. It i5 vnl1kely /hal all the sano'Jione ind,i;aled belong-s fo ll>e same horizon.
/V
ote
3.
WI!'!I data Or<' ana' may bt' sv
ba'jeercivletao' /rcoomnsoidrearlaabnledewrrrtoNre.nrt!'cord~
0 ~a ScALE.0 'h 1
'1
LANoiors
'
't.MIL~
MILE SQUARt