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It is an established fact that no large vertical section of this formation can be cut out of the stratigraphic column without eliminating zones of oil shale of a value well within the rule adopted by the United States Geological Survey for the classification of lands with respect to their oil shale character.
During the past six year, I have been actively engaged in the field in the details of the examination, sampling and testing of the major oil-yielding zones of this formation at many widely scattered localities. Also, I have had direct supervision of assessment work on tracts of oil-shale land covering many thousands of acres in extent. In the course of this work, I have had an opportunity to study the vertical and top exposure of the Green River formation over a broad expense of territory and to trace and correlate the lateral extension of the major oil-shale zones over many miles of outcrop.
The results of these observations have established such a remarkable lateral persistence and uniform stratigraphic distribution of the principal oil-shale zones as to permit of but one conclusion; that throughout the area under discussion, the major oil-shale zones persist with practically unbroken regularity and that wherever one establishes the presence of a certain oil-shale zone at the surface he is safe in assuming that he will find the other zones of the series occuping their respective horizons. The surface shale on top of these plateaus is necessarily low in oil content due to weathering and decomposition caused by the elements, but the existence of such shale on the surface is infallible evidence of the existence of the richer shales below. For instance, what is termed the Sandstone market is simply one series of the formation which infallibly lies above the red mahogany shale. This condition is not comparable to the ground beneath the surface of the earth where oil sands separated by hundreds of feet are penetrated but is comparable to coal, stone, marble quarries and great deposits of porphry copper where the rich zones are mingled with lean zones and all together form one great mass of valuable mineral bearing material.
For this reason there is in my opinion no reason for saying that the lean shale outcropping on the surface has no physical connection with the rich shales beneath the surface and are separate, distinct, and disconnected from them but on the contrary the lean shales are correlated with the richer shales in the Green River formation, all of which is extremely probable to be valuable for oil production without regard to rich and lean zones therein.
While certain horizons including the surface shale contain an abundance of characteristic fossils that serve to definitely establish their position in the stratigraphic column, it is seldom necessary to resort to such evidence in the identification of the various zones. The oil shale in each major zone is so different in physical characteristics from that of other zones that each zone weathers in characteristic forms at the outcrop and these peculiarities are generally sufficient for its identification and correlation. For instance, there exists near the top of the Green River formation, at a statigraphic elevation of 2,100 feet above the Wasatch or an altitude of 8,200 feet what is commonly referred to as the “ curly shale” zone. This zone is approximately 45 feet thick and is made up of five distinct strata of characteristic curly" or "* twisted " shale, ranging in thickness from 3 to 7 feet and yielding from 22 to 26 gallons of oil per ton. Between each seam occurs a thin bedded lean shale of entirely different characteristics than the "curly” shale. The curly shale has such distinct characteristics at the outcrop that even a novice could not fail in its identification. It is entirely unlike any other shale in the Green River formation. It can readily be identified by its warty and contorted outcrop. The warts represent inclusions of mud-balls which, because of their superior resistance to weathering, form wart-like projections on the weathered surface. Again, we have “geode" shale, the “bug-hole” shale of the miners; "paper" shale; "conchoidal” shale; “mahogany” shale; “streaked" or “ribbon” shale; and other varieties too numerous to mention. Space does not permit of detailed description of these many varieties but it may be said that all have their distinct characteristics which are known to the miners and are quickly recognized. It does not require expert knowledge to trace and correlate these various zones. In my opinion when one discloses shale on the surface of this area, he discovers all the shale from the Wasatch to the surface because they are physically connected in the same formation.
('ertain zones, such as the curly, paper and mahogany, assume such conspicious features in the surface topography of the region that one can trace their outcrops with the naked eye over hundreds of miles of exposures, while riding in an automobile along the valleys and tributary canyons. This will convey an idea of the ease of identification and correlation.
In the early literature on the geology of the oil shales of Colorado we find a reference to the upper, middle and lower parts of the Green River formation, which has been construed by some as indicating three distinct divisions of this formation. Statements have been made that of the three divisions, only the middle division is of economic importance. In my six years' experience in the field, I have found no evidence that would support such a view. While it is true that the middle part contains the richest zone in the formation there are important zones in the lower portion of the formation and at many horizons up to the base of the mahogany zone and from there to the top of the series. In fact, the vertical section from the base of the mahogany zone to the top member of the curly zone, representing an interval of from 500 to 550 feet, may be assumed, from an economic standpoint, to be a single body of oil shale and in all probability, will be mined as such when large-scale operations begin. The fact that there may be a few thin beds of sandstone included within this zone, or that parts of it may be very lean in oil content, will be of no consequence to the miner. He will mine sandstone, lean shale, and all and depend upon the richer portions to raise the average of the whole to an economic grade.
The metal miner does not confine his operations to thin, high-grade streaks of ore, if, by including larger masses of lean ore, he can obtain a lower unit cost in the production of his end product; nor would a shale miner be justified in resorting to selective mining if, by mining thick sections of relatively lowgrade shale, he can reduce the unit cost of his crude oil. Again, even though his cost per barrel be the same or a little high, he might still be justified in mining the large masses of low-grade material, if by so doing he can greatly augment his reserves of raw material and increase many fold his recovery of oil per acre of land and thus prolong the life of his enterprise.
The great Alaska-Juneau enterprise, which involved an original investment of close to $10,000,000, was based on estimated profits of 75 cents per ton from gold ore of an estimated value of $1.50 per ton. The Nevada Consolidated Copper Co. is now utilizing material, formerly considered waste, containing around 10 pounds of copper per ton, and many of the large “ porphry” copper mines have added to their reserves, millions of tons of material that formerly was regarded as of no economic value.
These facts are cited to illustrate the necessity of caution in appraising the prospective value of low-grade materials where they occur in enormous quantities and can be mined at a very low cost per ton, compared with the relatively high cost of mining thin deposits of rich material. It is a well known fact that the refined copped market is dominated by producers who have nothing but low-grade ore to draw upon and that this domination is the result of low-unit costs compared with relatively high costs of production from small bodies of ore of high value.
These facts, I believe, have an important bearing on the question as to what constitutes a sufficient discovery to support the claim of an oil-shale placer locator who is seeking or intends to seek patent under the general mining laws, and it is this idea that prompts me to submit them.
WILLIAM 0. PRAY.
Mining Engineer, De Beque, Colo. Mr. McMULLIN (continuing). The top of these plateaus is necessarily low in oil content. I asked Mr. Pray before leaving if he would kindly also furnish his views as to the effect of weathering where the shale is exposed on the surface, and since arriving here I received the following affidavit from him. STATE OF COLORADO,
County of Aesa: William 0. Pray, being duly sworn, on his oath deposes and says that he is a resident of De Beque, Colo.; is 48 years of age and a mining engineer by profession. That he has been engaged in oil-shale engineering for the past six years and is familiar with the effects of weathering on the outcrops of the oil shale deposits of northwestern Colorado.
That the surface exposures of oil shale are susceptible to the same processes of alteration and decay by atmospheric agencies as are the outcrops of coal seams and metalliferous deposits, and are found in various stages of decomposition, depending on the time and conditions of exposure, topographic environment, and the difference of resistance offered by shales of different character.
Physical structure is an important factor in the resistance to penetration. Shales of massive structure, whether lean or rich, are more resistant than are thin-bedded, platy, or papery shales. Thick-bedded “geode" shale, because of the presence of numerous vugs and large cavities, are more susceptible to attack than are thick-bedded massive shales. Certain shales, occurring at the base of the Green River formation, are perhaps, less resistant than any other type of shale, because of their peculiar foliiated structure and the presence of minute fossil shells in great abundance. The latter shales are found at the outcrop in an advanced stage of decomposition; with their original oil content greatly reduced, and their color bleached to various shades of buff or light brown.
Topographical environment is an important factor in controlling the depth to which weathering persists beyond the outcrop. The rate of transportation of weathered material away from its source determines, to a great extent, the depth to which the material near the surface will be found to be altered.
The rate of transportation varies with the topography. It is rapid on the steep slopes and escarpments, and relatively slow on the tops of plateaus and at the base of the mountain slopes; therefore it is reasonable to expect deeper and more advanced decomposition in the upland country and at the base of the plateau than on the steep declivities.
The relatively slow rate of transportation in the upland country favors the accumulation of a mantle of soil and subsoil which support vegetation, the latter, in turn, retarding erosion and aiding in the retention of moisture and thus promoting decomposition.
The weathering of rock is known to be at its best in the presence of moisture and vegetation. Deep snow accumulates on the tops of the plateaus, and be. cause of the gentle topography and relatively porous nature of the rocks at this horizon, much of the moisture is retained and aids in decomposition. Vegetation thrives, and the organic acids derived from the products of decayed vegetation, as well as from the roots of plants, have a profound influence in the promotion of deep-seated decomposition. For these reasons the outcrops of oil shale on the surface of the plateaus are subject to vigorous attack and deep penetration and we should expect to find them in an advanced stage of alteration and materially reduced in oil-yielding value.
Because of the fact that steep slopes favor rapid transportation of material, the weathering of outcrops is shallow and weathering does not keep far in advance of erosion; therefore, with the exception of densely timbered slopes and areas affected by burning and partial distillation of the shale, the shale found at the outcrop is in a relatively fresh stage of preservation, although certain varieties, with many planes of lamination and therefore many planes of penetration, are found in an altered ocndition 20 feet back of the outcrop.
In what is called the basal zone at the base of the Green River formation, deep-seated weathering is notably prevalent. Here we find dark brown to black shales of uniform texture and structure, intensely altered, in numerous localities, to bleached material yielding less than 50 per cent of its original oil content. In many places these shales will be found at surface in a relatively fresh condition, but in other places decomposition persists as deep as 30 feet from the outcrop, the material showing a gradual transition from weathered to unaltered shale. As previously mentioned, there are certain shales in this zone, characterized by their peculiarly foliated structure, that seem particularly susceptible of attack by weathering agencies. Where fresh, this variety of shale will be dark colored and of tough constitution, yielding from 12 to 16 gallons of oil per ton. In its extreme stage of weathering, it consists of soft, pulpy2 ppearing, buff-colored material, yielding but 5 to 8 gallons of oil per ton. There are other varieties of shale in this zone that are readily attached by weathering agencies, and show the same tendency to lose much of their oil-yielding value through the agency of surface decomposition.
WILLIAM 0. PRAY. Subscribed and sworn to before me this 26th day of November, A. D. 1926.
GEORGE W. HEPLIN, Notary Public. My commission expires February 10, 1930.
Mr. MCMULLEN (continuing). Mr. Secretary, I do not want to take the time of this gathering to say anything on the legal aspects surrounding these questions except to show the pertinence of these affidavits. The department seems to indicate that expects the locators to show on the surface-actually and phys cally exposed on the surface of the ground-oil shale with an oil content of at least 15 gallons per ton. We present these affidavits for the purpose of showing that this mountain with these correlated zones has successive areas of lean and rich material just like any other mineral formation. On the surface the weathering and decomposition is such that this rule works an unnecessary hardship, because when we find the shale on the surface we know that we have found the Green Giver formation which contains the rich and the lean together, all correlated and all physically connected. We have always understood that the mining statutes of these United States do not prescribe what is necessary to constitute discovery. Congress never attempted to define it. The courts have held that no arbitrary rule as to what will constitute a sufficient discovery can be stated which will govern all cases, even in respect to lode claims or placer claims. It may be stated generally that the term “ discovery,” as applied to a mining claim, means acquirement of knowledge that it is reasonably valuable for placer mining. It is not necessary that shale in paying quantities be found. On that question the courts of Alaska, California, Colorado, Idaho, Montana, Nevada, Oregon, and the circuit court of appeals and other Federal courts have ruled specifically. It is sufficient if shale is found under such circumstances and of such a character and quantity that a reasonably prudent man would be justified in expending time and money in developing it with the reasonable expectation of finding thereon shale in paying quantities.
Now, why is it, we ask, that there seems to be a disposition to apply a fixed rule relative to discovery and perhaps other questions when it has never been done before and it has never been recognized in regard to any other deposit? Here we have decisions covering metalliferous deposits and we have decisions covering fossiliferous deposits, and here we have a sedimentary deposit, and it was you, yourself, Mr. Smith, in 1916, that called the attention of the department to the fact that this deposit would be difficult to be brought within the provisions of the placer laws; and yet, Mr. Secretary, it was done. In 1916, after the Geological Survey published three different pamphlets calling the attention of the people of western Colorado to this great resource, the land was classified and the General Land Office declared that the land might be entered under the placer act. We came down here in 1915. The question of the disposition of this land in that area was then at issue. We went before the Sixty-sixth Congress, which formulated the leasing bill, and the Sixty-sixth Congress in that leasing bill put in a saving clause protecting the rights of these locators--and why? I have no doubt but what there is some disposition on the part of some people, perhaps overzealous, to talk about us as western speculators; and yet, gentlemen of the department, I want to say to you that we made our shale locations in 1916, 1917, 1918, and 1919 primarily because we understood it was a war resource and that it was a patriotic duty, and the Sixty-sixth Congress understood that and they protected those of us who had acted from that sense of duty.
Now what does this mean? How can you expect to find the conditions in a sedimentary formation that you do in a metalliferous formation? How can you expect to apply the rules, applicable to discovering a vein or lode in place in a mineral formation, to a sedimentary formation? I have argued this matter fully in my brief and am simply calling your attention to this matter at this time in order to preserve the continuity of this thought. We contend that the nature of the deposit permits us to show at all times facts which clearly and unequivocally-not geologically inference but absolutely--established that this land is valuable for oil shale and no other purpose. It is not valuable for agriculture. I think the records of this department will show that the department refused to establish a forest reserve in this country because of that fact. It is valuable for nothing else, and yet we can take this land and through it develop what everybody considers to be a great and coming necessary industry. Even now in this country we looking forward to the time when the mineral oil supply will be below the demand. How does your department expect this resource to be developed? How do you expect this industry that will take millions of dollars to be developed unless you remove these restrictions which we believe are unwarranted by the facts, and adopt an attitude which will permit those who in good faith acquired their properties from various locators to go ahead and perfect their titles; who will pay this Government $2.50 an acre for otherwise valueless land; who are prepared to go ahead and develop this industry which will take millions and millions of dollars? Is not this necessary in order to create a demand for the larger area of this land still held by the Government?
Now in conclusion I want to say I have my printed briefs here with copy of this paper, which I desire to file with you. I have lived in western Colo
rado for 37 years. I made my first shale locations 13 years ago. I have traveled across this country time and time again without any financial reward to this hour to secure the capital for the purpose of developing this industry. We people in western Colorado realize it because we are living in its atmosphere, but we are not any more interested than you here. It is a great potential resource of this country and it should be aided in every legitimate manner,
(At this point Mr. McMullin presented to the secretary a large photograph showing a typical oil-shale formation. The photograph was filed with the other papers of the record.)
I desire to file that photograph with my briefs, Mr. Secretary, and thank you for your attention,
Mr. HAWLEY. Mr. William C. Russell, a mining engineer of Denver, will be the next speaker.
Mr. RUSSELL. Mr. Secretary and friends: I will dispense with any preliminaries and at once proceed to read the statement which I have prepared on the subject of " discovery." I was uncertain at the time I wrote this statement or article whether I should be present to read it or not, and I have therefore addressed it in the form of a letter to the Secretary.
WASHINGTON, D. C.. December 1, 1926. To the Hon. SECRETARY OF THE INTERIOR,
Washingion, D. C. In re: Discovery on Oil Shale Placers.
MY DEAR DR. WORK: In recognition of your call for a public hearing at Washington beginning this 1st day of December, 1926, on the question of what constitutes a “ discovery” within the meaning of the law, on an oil shale placer mining claim, I have the honor to submit for your consideration a few facts covering my observations gained over a period of 28 years as a mining engineer, including 9 years practical experience as such, in the oil shale fields of the West.
It is indeed much to your credit, our Honorable Secretary, that you have opened wide the doors for a full and candid discussion of the whole question of discovery as affecting oil shale placers, for it has appeared that certain members of your department have been acting under a misunderstanding as to the nature of the oil shale deposits and as a result of such misunderstanding have undertaken to set up a schedule of limitations as to the quantity of oil that a given thickness of shale must produce as one of the prerequisites to a patent. It appears that they have been inclined to take the rules which were prepared by the Geological Survey for the guidance of its field force in the classification of the western oil shales and write them into the general mining law of the land.
It seems hardly possible that the Survey had any notion, when it framed the schedule, of upsetting the very foundation of our mining law by injecting into it a new interpretation of the term “discovery." Luwmaking is quite outside the sphere of the Survey's authority, and it is unbelievable, therefore, that it should presume upon the prerogatives of ('ongress. The Survey's oil shale schedule may have served its purpose well as a guide for the field force in their work of land classification, but it should have no bearing or influence whatever upon the discovery question, and it certainly has no standing as a practical operating guide in determining what is commercial and what is noncommercial oil shale. However, the advocates of this schedule have succeeded in carrying it along far enough to cause more or less disturbance and to entail considerable unnecessary expense among certain shale land claimants, and it is, therefore, to be hoped that the results obtained through an open and candid discussion of the whole shale problem will set at rest for all time the fallacy of establishing limitations on shale land discovery. Only upon rare occasions hitherto in the entire history of the mining industry of the United States have limitations on discovery been seriously considered either by the Department of the Interior or by the courts. It seems safe, therefore, to predict that when all the facts with respect to the physical and economic conditions which surround the oil shales shall have been laid before you, that you will find no place for any schedule of values whatever, but that you will be entirely satisfied to permit the laws and precedents which have hitherto governed “ discovery " on both lodes and placers, to prevail.
Although oil shale lands have been properly classified as placers and are placers in the sense that they are of sedimentary origin, yet at the same time, as a practical proposition they come nearer being lodes than placers, if for