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By S. Brunauer

The hydration of portland cement is treated as a chemical reaction and the changes in matter, in energy and the rate of change of the process are discussed, Portland cement is a mixture of four major and at least as many important minor constituents. In the hydration process, the four major compounds (trical-cium silicate, dicalcium silicate, tricalcium alumi-nate and tetracalcium aluminoferrite), plus gypsum and water form five or six new compounds. In spite o the great complexity of the reaction, considerable progress has been made in its understanding, primarily with the help of such research tools as X-ray diffraction and electron microscopy. The rate of the reaction can be followed by direct and indirect methods of measurements. The effects o composition, particle size (or specific surface), temperature and water-cement ratio on the rates of hydration are discussed. The hydration of portland cement is a chemical reaction accompanied by such highly important physical phenomena as heat evolution, setting and hardening. It is a vast and complex subject, on which hundreds of papers have been published. At the time of the writing of this paper, in October 1962, a two-volume book, which alone contains dozens of papers pertaining to cement hydration appeared in print.' The present paper deals with a few aspects of this vast subject, and the selection was not easy. The work reported here deals with some of the most recent investigations in the field. In any chemical reaction, the physical chemist is primarily interested in three things: changes in matter, changes in energy and the rate of change of the process or the speed of the reaction. This is true also of the chemical reaction between portland cement and water, and all three aspects of the reaction will be discussed. These three aspects are of vital interest to the engineer as well. Portland cement is not a cementing material — the hydration products, the new materials which form in the reaction, have the cementing action. The energy changes manifest themselves in a considerable evolution of heat, which may be useful or harmful. It is useful, for example, in winter concreting, but in very large concrete structures like dams, a large evolution of heat, which cannot be easily dissipated, may produce distress in the structure. Primarily for such a purpose was the Type IV or low heat portland cement developed. The speed of the chemical reaction is important because it determines the time of setting and hardening. The initial reaction must be slow enough to permit placing of the concrete before setting occurs. On the other hand, after the placing of concrete it is often highly desirable to obtain as rapid chemical reaction as possible. For this purpose the Type 111 or high early strength portland cement was developed. CHANGES IN MATTER Portland Cement: In a basic investigation, before one begins to study a reaction, one either knows the quantities and compositions of the starting materials, the reactants, or one determines them. This is obvious; the chemist expresses the changes in matter that occur in a reaction by a chemical equation, which has the quantities and compositions of the reactants on the left side of the equation and the quantities and compositions of the reaction products on the right side. The first question is then what to put on the left side of the equation in the reaction between portland cement and water? It is not very easy to answer this question. Portland cement is not a single chemical compound but a mixture of many compounds. Four of these are considered the major compounds, and at least four of the minor compounds also play important roles in the hydration reaction. In order to avoid complicating matters, the present discussion will be restricted primarily to the four major compounds, which constitute usually more than 90% of a portland cement. The relative amounts of these compounds vary from cement to cement. Actually not only the amounts but the compositions of these constituents also vary to some extent, but the variation in composition of the individual components will be neglected for simplicity.

Jan 1, 1963

By J. Chupak, D. J. Salley, G. L. Simard

Radiotracers were demonstrated to be of considerable value in a study of the interaction of dithiophosphate with galena. The interaction had characteristics of both chemisorption and chemical reaction, being complex because of the nature of the galena surface. Sorption was rapid and markedly reversible, and flotation occurred at relatively small amounts of dithiophosphate sorbed.

Jan 1, 1950

By O. I. Deschon, Ralph Arnold

Deep drilling was the keynote of the more important developments in the North Rocky Mountain region during 1929, with Montana recording the most important achievement through discovery of three new oil fields. Alberta produced 1,000,000 bbl. of 74 gravity naphtha, showing a considerable gain over 1928, developed a commercial oil pool in Turner Valley and extended that field 8 miles southward. Wyoming's discovery field was deepened to a second producing horizon, giving impetus to deeper drilling, and practically every Wyoming oil field will have a deep test either this year or in the near future. Whereas Montana prospecting has been confined to the shallow plains structures, since the discovery of Kevin-Sunburst field, the coming year will see an active search for new oil and gas pools in sharp-dip structures, following the success of prospecting in the Sweetgrass Hills during 1929. A dozen or more structures have been mapped in North Central Montana, several of these straddling the Alberta border. Four structures tested thus far have all shown commercial oil or gas or both. Sweetgrass Hills The first important development in the Hills area was the Rogers-Imperial gasser, which had an initial of 51,000,000 cu. ft. of dry gas per day, with a rock pressure of 1080 lb. This well is located on a sharp nose running north from the hills into Alberta. Several wells drilled by independent operators on the American side, on the west flank of reserve structure, have developed a total open flow capacity of 30,000,000 cubic feet. The third structure tested in the Hills area is known as Bears Den, where commercial oil was found at the base of the Cretaceous at 2470 ft. The existence of oil in three lower sands has been established by two wells on the top of the structure, these two wells finding gas flows of 10,000,000 and 15,000,000 cu. ft., respectively, in the horizon where

Jan 1, 1930

By George J. Young

DURing the spring of 1910 1 visited a number of open-pit brown-coal mines and underground workings in the vicinity of Halle, Halberstadt, Leipsic, Cologne and Bonn. The notes which I took and the observations which I made at the time have been condensed and make up the principal part of this paper. Certain supplementary information has been taken from several sources which are given in the paper. The mining of brown coal is one of the important industries of Germany. The coal varies in color from dark brown to almost black and is soft like loam. Pieces of wood and strips of bark and even parts of tree trunks are frequently encountered in the excavation although the coal for the most part consists of a pulverulent, more or less matted mass of small particles of vegetal matter. It is a product between peat and lignitic coal. An analysis, taken from Coal Resources of the World shows the approximate composition of the material: Moisture, 53.73 per cent.; ash, 4.98; fixed carbon, 18.08; volatile carbon, 23.31 per cent. Thc principal characteristic is the amount of moisture. This seldom runs less than 48 per cent. The ash is usually low and ranges from 5 to 10 per cent. The sulphur content is usually less than 0.5 per cent. The heating effect of the fuel ranges from 2,000 to 2,500 calories. The commercial deposits are confined to the Tertiary period although

Jan 1, 1916

By Krahmann, Rudolf

THE following is an account of a survey undertaken to test the possibility of outlining a kimberlite pipe by magnetouietric methods. Kimberlite is a basic igneous rock closely related to melilite-basalt or alnoite, which occurs either in the form of volcanic plugs or as dikes intruded into rocks of various types and geological ages up to and includ¬ing the Lower Cretaceous. The famous diamond mines of South Africa are all in kimberlite pipes and these pipes are probably the original source as well of the vast alluvial deposits found in various parts of the country. The pipe chosen for this experiment is one that ' occurs on the farm Goedgevonden No. 20, about sixteen miles north of the village of Klerksdorp and ninety miles southwest of Johannesburg. Some prospecting has been done on this pipe and diamonds were produced from it but not in paying quantities. The magnetometric survey was made in June, 1932, by R. Krahmann and H. Wallisch and the results are shown on the accompanying plan. On the plan are shown also the boundaries of the pipe as exposed at the surface and details in regard to the surrounding foundations. These are taken from a geological survey made at a later date by W. Beetz, of Johannesburg.

Jan 1, 1935

By C. C. Hawes

SILICA is the main impurity in iron ore. It is intimately associated with the iron oxide, sometimes free but more often in the combined state, as a mineral silicate. Its separation and purification sometimes present difficult problems to the analyst. In the absence of any definite knowledge to the contrary, orthosilicic acid. H4SiO4, is supposed to be the only silicic acid made, all other forms, such as metasilicic acid, H2SiO3, representing different degrees of its dehydration. These acids are exceedingly weak but form the most stable compounds found in nature. They are known as the silicate minerals and are formed by the combination of the different metallic oxides

Jan 1, 1936

By J. A. Heskett

NEW ZEALAND is dependent on the outside world for its ferro goods, yet it can boast of at least two well-defined iron-ore deposits; namely, Para Para limonite, 3 Fe203 + 21120 also found as lower hydrated oxides, and Taranaki iron-sand, a combined magnetite and ilmenite, 2FeO + 2Fe203 + FeO + Ti02. The former is of massive variety and the FIG. 1.-VIEW OF WORKS SHOWING IRON-SAND DEPOSITS, ALSO WHARF AND BREAK¬WATER IN THE DISTANCE. latter granular and mixed with various proportions of fine shell and siliceous sand well water-worn. This latter deposit forms the greater portion of the beach sands of the west coast of the North Island of New Zealand. It is so fine that the whole of a sample passed through a sieve of 40 meshes to the inch. The ilmenite cannot be detected by the microscope, as in the titaniferous ores of the Adirondacks, nor can it be magnetically separated, as in the titaniferous ore of Natashkwan, Canada. To all appearances it is a chemical compound of the double oxides of iron and titanium and not a mechanical mixture, as is the ore of the Adirondack deposits.

Jan 8, 1920

By V. H. Wilhelm

The trend initiated in January 1936, of stabilized gasoline prices, increased demand and extraordinary drilling activity, continued in California during the year 1937. Crude prices were maintained during the year at the highest level since September 1930. Wildcat activity with resultant new discoveries and development of proven acreage were greater than in any year since 1928. Many fields in California in former years have been produced at full capacity, with consequent loss of reservoir energy, but at the present time continued activity is maintained to develop adequate reserves, so that production in these fields can be taken at a rate to correspond with good operating practice. Naturally, this good operating practice will be influenced to some degree by gas outlets and, in certain instances perhaps, by oil outlets. In any event, these last two controlling features will result in favorable rather than detrimental operation. In fields producing from great depths, ultimate production will be practically limited to the flowing and compressor life of the well, since there is as yet no economical method for pumping wells below depths of approximately 7000 ft. Experience has shown, however, that such pumping difficulties will be overcome and that production secured by pumping will add some to reserves established on the flowing life of the wells. California continued to operate under voluntary curtailment, but with unlimited transfers of allowable between various fields. Even though there was at all times considerable production above the Umpire's established quota, a constantly increasing demand reduced storage during the year. This increasing demand was due mainly to the rapid rise in Pacific foreign shipments from May to September. It is questionable, however, whether this favorable condition will be maintained over a prolonged period. (See Fig. 1.) Field Discoveries The great drilling activity during the year resulted in the discovery of three new fields in the San Joaquin Valley, as well as many extensions

Jan 1, 1938

By V. T. BERNER

THIS apparatus was designed primarily to meet the demand for a quick, efficient stopping to seal off the burning area temporarily during a mine fire, but it can be used in any circumstance where an immediate brattice is required for ventilation control. In using the old style brattice, mine-rescue workers have found it difficult, in smoke-laden drifts and stopes, to erect an effective stopping with wooden frame and canvas. Stulls must first be cut to the proper length, the canvas tacked in place, and the numerous irregularities of the walls and back must be caulked. This operation requires the employment of axes, saws, and hammers, which cannot easily and safely be handled in dense smoke. The fire fighters have often been forced to abandon their brattice, unfinished, because of the rapid approach of the fire, or because of the exhausted sup- ply of oxygen in their breathing apparatus. It is neces-

Jan 1, 1930

By Sadao Maruyama

INTRODUCTION Since the big discovery of Kuroko deposits in Kosaka mine, Akita Pref., northeastern Japan in 1959, major Japanese mining companies have been engaged in extensive exploration for the deposits expending large amounts of money. Above all their exploration activities have been particularly fruitful in discovering new deposits in northern Akita Pref. It is estimated that the total ore reserves newly found in the area are at least 50 million tons. Kuroko deposits are the most important ore source of copper, lead and zinc in Japan and have been mined since last century in the said area. Kuroko (black ore) is fine, compact aggregates with sphalerite , glena and barite as principal constituents and chalco- pyrite, pyrite and tetrahedrite as subsequent constituents. The name Kuroko comes from its appearance. It is not rare that total grade of copper, lead and zinc reaches 20 - 30% and the gold and silver content is also fairly good. Accordingly the unit value of the ore is much higher than the ore from other types of deposits. Besides the Kuroko ore, the Kuroko deposits consists of Ohko (yellow ore, massive cupriferous pyritic ore), Keikoh (silicious ore, cupriferous network ore) and gypsum ore. This type of deposit is considered to be not only an important source of base metal but also a source of gypsum and barite. Although the importance of this type of deposit had been commonly recognized, sub-surface nature of the occurrence hampered exploration work. In recent years the improved exploration techniques and increased knowledge of the Kuroko deposits have met with remarkable success in the location of new deposits. This outburst of exploration and dis-

Jan 1, 1970

By J. B. Umpleby

The function of gas in the development and production of oil has far-reaching consequences that should be emphasized. The technical aspects of the subject have recently had a great deal of attention but less thought has been given to fundamental concepts underlying oil and gas law and the many customs and practices that have grown up in the industry. I shall review briefly the advance in knowledge of the subject and attempt to relate these concepts to legislative, judicial and operating problems. Early writers on oil and gas in Pennsylvania noted their close association in oil pools and their contemporaneous decline in output; also, that as gas pressure decreases so does production, that new offset wells reduce the output of existing wells, and even that tubing a well lengthens its flowing life. Expanding gas was deduced as the principal expulsive force. These fundamental observations had been made at least as early as 1880.1 They were treated, however, as academic considerations and did not greatly influence law or practice for many years except to instill into all operators an urgent desire to hasten offset drilling in order to obtain as much of the flush as possible. The most noteworthy later advance in knowledge came in 1926 when Beecher and Parkhurst published their paper on Effects of Dissolved Gas upon the Viscosity and Surface Tension of OiL.² This paper added to the old idea of an expelling force the concept of a modifying agent that actually changes the physical characteristics of the oil and facilitates its movement through the pore spaces of the reservoir rock. Largely since the publication of this paper, intensive study and concerted effort have been given to means of using to a maximum, in producing oil, these combined properties of gas. This is shown clearly by the number of papers dealing with the subject, and the new and revived terms now widely used to express thought, such as the expressions gas energy, reservoir pressure, reservoir energy, gas-oil ratio, bottom-hole pressure, beaning, tapered tubing and back-pressure. These terms, some of which are

Jan 1, 1932

By C. O. Lee, R. H. Feierabend, Z. W. Bartlett

DESPITE the fact that American brimstone production has increased 2 times since the prewar period 1935-1939, the demand for sulphur exceeds the supply. To alleviate this situation efforts are being made to increase the production of sulphur and bring the shortage to an end. The most important developments are being undertaken on the Gulf Coast. One new brimstone mine has been put into operation and three others are being developed. These projects are expected to account for a large part of the additional sulphur production now anticipated for the free world.'.' Except for a small amount of byproduct sulphur from sour natural gas and refinery gases, American brimstone is produced by the same process devised by Frasch 60 years ago, consisting essentially of the injection of superheated water at about 325°F into sulphur-bearing formations through wells which are drilled from the surface by standard oilfield methods. Sulphur deposits vary in depth from a few hundred feet to 2500 ft from the surface; in a typical deposit the sulphur occurs as crystalline aggregates in porous limestone and gypsum in concentrations varying from 5 to 40 pct, the thickness of the formation ranging from a few feet to several hundred.3 The deposits are usually surrounded by formations impermeable to the flow of hot water, the top and sides being enclosed by impermeable sediments and the bottom by dense impermeable anhydrite. As the hot water leaves the well bore, it percolates through the formation and transmits its heat to the rock and sulphur. When the sulphur reaches 240°F it melts, separates from the rock, and flows through the hot channels downward to the bottom of the well. Here it is freed from incoming water and from formation water, which saturates the porous rock, by gravity separation, liquid sulphur being 1.8 times as heavy as water. It then is pumped to the surface in a relatively pure state, 99.5 pct or better. Chief contaminants are organic impurities, such as petroleum residues, which are soluble in sulphur and tend to discolor it.' Sixteen deposits of commercial magnitude have been discovered in the Gulf Coast area. Five of these deposits have been depleted and abandoned with production totalling more than 26,886,000 tons. Eight properties are operating and have produced 65,875,-000 tons to Jan. 1, 1952, for a total Frasch-type production of 92,761,000 tons. Three new deposits are under development. Aforementioned deposits are listed in Table I. Each of these deposits has been found in the cap-rock overlying shallow intrusive salt plugs or domes and buried in several hundred to as much as 2500 ft of sediments. All salt domes do .not contain sulphur; only 16 sulphur deposits have been found in a total of 231 salt domes which are known to exist in the Gulf Coastal states of Texas, Louisiana, Mississippi, and Alabama. Ten of the salt domes lie in the Gulf of Mexico offshore from the Texas and Louisiana coasts. Additional offshore domes may be found, but their value as a sulphur potential is questionable owing to the great hazard and high cost that can be visualized at these exposed locations where depths of water reach 50 ft. Marsh operations of Freeport Sulphur Co. are in the southeast section of Louisiana. In general, the country is low, flat, relatively uninhabited marshland broken by many shallow lakes and bayous which extend for irregular distances inland. Geologically, the coastal area is of sedimentary origin, having been built up gradually under the sea by deposition of material carried down by large streams to their deltas. Offshore bars were formed enclosing

Jan 1, 1953

By C. O. Lee, Z. W. Bartlett, R. H. Feierabend

DESPITE the fact that American brimstone production has increased 2 times since the prewar period 1935-1939, the demand for sulphur exceeds the supply. To alleviate this situation efforts are being made to increase the production of sulphur and bring the shortage to an end. The most important developments are being undertaken on the Gulf Coast. One new brimstone mine has been put into operation and three others are being developed. These projects are expected to account for a large part of the additional sulphur production now anticipated for the free world.'.' Except for a small amount of byproduct sulphur from sour natural gas and refinery gases, American brimstone is produced by the same process devised by Frasch 60 years ago, consisting essentially of the injection of superheated water at about 325°F into sulphur-bearing formations through wells which are drilled from the surface by standard oilfield methods. Sulphur deposits vary in depth from a few hundred feet to 2500 ft from the surface; in a typical deposit the sulphur occurs as crystalline aggregates in porous limestone and gypsum in concentrations varying from 5 to 40 pct, the thickness of the formation ranging from a few feet to several hundred.3 The deposits are usually surrounded by formations impermeable to the flow of hot water, the top and sides being enclosed by impermeable sediments and the bottom by dense impermeable anhydrite. As the hot water leaves the well bore, it percolates through the formation and transmits its heat to the rock and sulphur. When the sulphur reaches 240°F it melts, separates from the rock, and flows through the hot channels downward to the bottom of the well. Here it is freed from incoming water and from formation water, which saturates the porous rock, by gravity separation, liquid sulphur being 1.8 times as heavy as water. It then is pumped to the surface in a relatively pure state, 99.5 pct or better. Chief contaminants are organic impurities, such as petroleum residues, which are soluble in sulphur and tend to discolor it.' Sixteen deposits of commercial magnitude have been discovered in the Gulf Coast area. Five of these deposits have been depleted and abandoned with production totalling more than 26,886,000 tons. Eight properties are operating and have produced 65,875,-000 tons to Jan. 1, 1952, for a total Frasch-type production of 92,761,000 tons. Three new deposits are under development. Aforementioned deposits are listed in Table I. Each of these deposits has been found in the cap-rock overlying shallow intrusive salt plugs or domes and buried in several hundred to as much as 2500 ft of sediments. All salt domes do .not contain sulphur; only 16 sulphur deposits have been found in a total of 231 salt domes which are known to exist in the Gulf Coastal states of Texas, Louisiana, Mississippi, and Alabama. Ten of the salt domes lie in the Gulf of Mexico offshore from the Texas and Louisiana coasts. Additional offshore domes may be found, but their value as a sulphur potential is questionable owing to the great hazard and high cost that can be visualized at these exposed locations where depths of water reach 50 ft. Marsh operations of Freeport Sulphur Co. are in the southeast section of Louisiana. In general, the country is low, flat, relatively uninhabited marshland broken by many shallow lakes and bayous which extend for irregular distances inland. Geologically, the coastal area is of sedimentary origin, having been built up gradually under the sea by deposition of material carried down by large streams to their deltas. Offshore bars were formed enclosing

Jan 1, 1953

By C. O. Lee, Z. W. Bartlett, R. H. Feierabend

DESPITE the fact that American brimstone production has increased 2 ½ times since the prewar period 1935-1939, the demand for sulphur exceeds the supply. To alleviate this situation efforts are being made to increase the production of sulphur and bring the shortage to an end. The most important developments are being undertaken on the Gulf Coast. One new brimstone mine has been put into operation and three others are being developed. These projects are expected to account for a large part of the additional sulphur production now anticipated for the free world.1,2 Except for a small amount of byproduct sulphur from sour natural gas and refinery gases, American brimstone is produced by the same process devised by Frasch 60 years ago, consisting essentially of the injection of superheated water at about 325°F into sulphur-bearing formations through wells which are drilled from the surface by standard oilfield methods. Sulphur deposits vary in depth from a few hundred feet to 2500 ft from the surface; in a typical deposit the sulphur occurs as crystalline aggregates in porous limestone and gypsum in concentrations varying from 5 to 40 pct, the thickness of the formation ranging from a few feet to several hundred.3 The deposits are usually surrounded by formations impermeable to the flow of hot water, the top and sides being enclosed by impermeable sediments and the bottom by dense impermeable anhydrite. As the hot water leaves the well bore, it percolates through the formation and transmits its heat to the rock and sulphur. When the sulphur reaches 240°F it melts, separates from the rock, and flows through the hot channels downward to the bottom of the well. Here it is freed from incoming water and from formation water, which saturates the porous rock, by gravity separation, liquid sulphur being 1.8 times as heavy as water. It then is pumped to the surface in a relatively pure state, 99.5 pct or better. Chief contaminants are organic impurities, such as petroleum residues, which are soluble in sulphur and tend to discolor it.4 Sixteen deposits of commercial magnitude have been discovered in the Gulf Coast area. Five of these deposits have been depleted and abandoned with production totalling more than 26,886,000 tons. Eight properties are operating and have produced 65,875,000 tons to Jan. 1, 1952, for a total Frasch-type production of 92,761,000 tons. Three new deposits are under development. Aforementioned deposits are listed in Table I. Each of these deposits has been found in the caprock overlying shallow intrusive salt plugs or domes and buried in several hundred to as much as 2500 ft of sediments. All salt domes do not contain sulphur; only 16 sulphur deposits have been found in a total of 231 salt domes which are known to exist in the Gulf Coastal states of Texas, Louisiana, Mississippi, and Alabama. Ten of the salt domes lie in the Gulf of Mexico offshore from the Texas and Louisiana coasts. Additional offshore domes may be found, but their value as a sulphur potential is questionable owing to the great hazard and high cost that can be visualized at these exposed locations where depths of water reach 50 ft. Marsh operations of Freeport Sulphur Co. are in the southeast section of Louisiana. In general, the country is low, flat, relatively uninhabited marshland broken by many shallow lakes and bayous which extend for irregular distances inland. Geologically, the coastal area is of sedimentary origin, having been built up gradually under the sea by deposition of material carried down by large streams to their deltas. Offshore bars were formed enclosing

Jan 1, 1952

DAVID WHITE,* Washington, D. C.-This paper is very timely since the Philippine Islands are presumably open to the enterprise of the American driller, whereas much of the territory in that part of the world is closed to us. The United States has ambitious plans for the operation of a great merchant marine, which is to be oil burning in the main, and it takes but a glance at the world map to see the strategic advantage of oil supplies in the Philippines for such marine operations. It is a little difficult to understand why more attention has not been given to the Philippines, in spite of the difficulties attending development in these islands. A number of American oil companies are, I believe, at the present moment taking an interest in the possibilities of the Philippines. Important factors in the formulation of opinion regarding the importance of the oil deposits of the Philippines, as brought out by Mr. Pratt,1 are the point of view and the breadth of experience of the examining geologist. The average oil geologist, whose experience has been mainly in the Appalachian region, the Mid-continent, or Louisiana, or possibly even in California, on seeing the narrowness of the basins, the closeness of the folding, and the presence of igneous rocks here and there, would be likely to draw unfavorable conclusions as to the possibilities of the Philippine Islands. Geologists visiting that region should be familiar with the geological conditions of oil occurrence in Japan, Formosa, the East Indies, or in the Baku district, and their conclusions should be formulated with the knowledge and understanding of the occurrence of oil in those regions rather than in the United States.

Jan 8, 1920

By C. H. Brehaut, W. N. Taylor, R. S. Douglas, H. A. Shannon

THE name for this new method of mining is derived from a composition of Horizontal, Radial, Diamond, and the drilling is from raises. This method, worked out at Copper Mountain, B.C., is believed to be distinct in many features from other known methods. GEOLOGY The ore deposits of Copper Mountain are related to the Copper Mountain stock, which is an ideal example of the magmatic differentiation in that it grades from a basic gabbro at the border to an almost pure orthoclase-pegmatite core. The "contact" ore bodies lie along the contact of the gabbro and an older complex of volcanics and sediment termed the "Wolfe Creek" formation. These older rocks, collectively referred to as greenstone, had been fractured prior to the intrusion of the stock and were highly metamorphosed during the intrusion. The "outlying" ore bodies are somewhat different in character, though a similar structural pattern prevails. It is believed that a deep-seated magma of which the Copper Mountain stock is a part has given off solutions that caused a partial granitization of some of the volcanics. Mining problems are caused further by the presence of a series of soft barren dikes intersecting a great many of the ore bodies, which are about 30 ft. wide, strike north-south, and dip at a high angle to the east; and are further increased by the presence of four major faults, with a great many minor faults running at acute angles from them. Fault zones average 8 ft. in width, and consist of gouge and breccia. They strike northeast and dip steeply to the northwest. The faults cut through the ore zones and the dikes, and continue on into the gabbro. The general mine structure with two types of ore bodies, bounded by weak walls and intersected by several series of soft barren dikes and major faults, indicated that a method of mining should be devised that would remove the ore at low cost with the least disturbance of the waste walls and dikes. THEORETICAL ESTIMATE OF STOPING WITH THE DIAMOND DRILL After consideration of various methods, the most suitable one appeared to be horizontal drilling to break the ore in a manner similar to shrinkage stoping. Drilling vertical holes or rings from a bench and breaking to an open slot was eliminated because the weak walls of ore, dike or waste would not permit this type of opening. It was then decided to drill either horizontal radial holes from a raise or parallel holes from a slot cut across the ore body. After discussion, the latter method was believed unsuitable, for the following reasons:

Jan 1, 1945

By Louise Barton Freeman, Coleman D. Hunter

The total production of oil in Kentucky during the year 1943 reached 7,010,776 bbl., which is more than at any time since 1930. Of this total, 5,287,659 bbl. was produced from the counties west of the Cincinnati arch, 692,359 bbl. from the 18 new pools opened during the year, and 3,260,765 from the Smith Mills pool, which was discovered in August of 1942. This is an important increase in western Kentucky in spite of the low price of crude, and demonstrates effectively the desire of the industry to cooperate in meeting the increased demands made by the war. Western Kentucky Two deep tests were drilled in the Kentucky portion of the Mississippi Embayment this year. Both were drilled to test the St. Peter. One well, drilled in Marshall County by the Adams Oil and Gas Co., did not encounter any St. Peter sandstone but drilled 650 ft. of formation below the position of the St. Peter and above the true Knox dolomite. The other well, in Ballard County, was reported to have tested the St. Peter and to have been temporarily abandoned at 3069 ft. At this depth the well probably was stopped in about the same formation as the Marshall County well. No accurate information is available on the Ballard County well. Several new producing areas were added to the list of fields in the western Kentucky coal basin, in Daviess, Henderson, McLean, Ohio, Union and Webster Counties. The Smith Mills pool was enlarged and production was found in the McClosky (Ste. Genevieve) in addition to the Cypress sandstone from which much of the earlier production had been obtained. There was some interest during the year in testing the Devonian and Silurian formations in the area south and east of the western Kentucky coal basin. In the fall of 1943, a 15 to 20-bbl. well was drilled in Allen County and two more wells are now being drilled. The production was obtained from within a few feet of the base of the Chattanooga black shale, probably in the upper Silurian. One well in Simpson County was drilled completely through the Silurian section before it was abandoned. Several wells were drilled in Logan, Todd and Christian Counties to test the Devonian where it is thinned by removal of the upper formations before deposition of the Chattanooga shale. None of these wells was successful but several other locations are now being tested. The Silurian thins in like manner on the eastern flank of the coal basin as the crest of the Cincinnati arch is approached, and it is along this thinning edge that such fields as the LeGrande, Logsdon Valley, Magnolia, Bowling Green and the Barren County pools were developed. A number of wells were drilled around these old pools in an effort to extend them, some of which were successful. The wells listed this year in Larue, Hardin, Barren, Hart and Warren Counties were drilled in the search for other such fields.

Jan 1, 1944

By Louise Barton Freeman, Coleman D. Hunter

The total production of oil in Kentucky during the year 1943 reached 7,010,776 bbl., which is more than at any time since 1930. Of this total, 5,287,659 bbl. was produced from the counties west of the Cincinnati arch, 692,359 bbl. from the 18 new pools opened during the year, and 3,260,765 from the Smith Mills pool, which was discovered in August of 1942. This is an important increase in western Kentucky in spite of the low price of crude, and demonstrates effectively the desire of the industry to cooperate in meeting the increased demands made by the war. Western Kentucky Two deep tests were drilled in the Kentucky portion of the Mississippi Embayment this year. Both were drilled to test the St. Peter. One well, drilled in Marshall County by the Adams Oil and Gas Co., did not encounter any St. Peter sandstone but drilled 650 ft. of formation below the position of the St. Peter and above the true Knox dolomite. The other well, in Ballard County, was reported to have tested the St. Peter and to have been temporarily abandoned at 3069 ft. At this depth the well probably was stopped in about the same formation as the Marshall County well. No accurate information is available on the Ballard County well. Several new producing areas were added to the list of fields in the western Kentucky coal basin, in Daviess, Henderson, McLean, Ohio, Union and Webster Counties. The Smith Mills pool was enlarged and production was found in the McClosky (Ste. Genevieve) in addition to the Cypress sandstone from which much of the earlier production had been obtained. There was some interest during the year in testing the Devonian and Silurian formations in the area south and east of the western Kentucky coal basin. In the fall of 1943, a 15 to 20-bbl. well was drilled in Allen County and two more wells are now being drilled. The production was obtained from within a few feet of the base of the Chattanooga black shale, probably in the upper Silurian. One well in Simpson County was drilled completely through the Silurian section before it was abandoned. Several wells were drilled in Logan, Todd and Christian Counties to test the Devonian where it is thinned by removal of the upper formations before deposition of the Chattanooga shale. None of these wells was successful but several other locations are now being tested. The Silurian thins in like manner on the eastern flank of the coal basin as the crest of the Cincinnati arch is approached, and it is along this thinning edge that such fields as the LeGrande, Logsdon Valley, Magnolia, Bowling Green and the Barren County pools were developed. A number of wells were drilled around these old pools in an effort to extend them, some of which were successful. The wells listed this year in Larue, Hardin, Barren, Hart and Warren Counties were drilled in the search for other such fields.

Jan 1, 1944

By C. WIFLARD HAYES

(New Haven Meeting, February, 1909.) I DESIRE to make it perfectly clear at the outset that I fully realize the hazardous nature of any attempt to estimate the quantity of iron-ore or any other mineral in the ground. I should not have had the temerity to venture upon an inventory of the iron-ore supplies of the United States except for the requirements of the Conservation Commission. During the preparation of this inventory I have been impressed by the wide diversity in estimates of those best qualified to. hold an opinion, and I am therefore prepared in advance for criticism of my figures. Inasmuch as this report was prepared in large part for unprofessional readers, I considered it necessary to classify and describe the commercial iron-ores in a somewhat elementary manner, in order to explain the reasons for the large element of uncertainty in the estimates. I have therefore given a chemical and a geological classification of iron-ores, which place the commercial deposits in six classes: (1) magmatic segregations in basic igneous rocks; (2) contact-deposits formed in connection with igneous intrusions; (3) concentration-deposits; (4) replacement-deposits; (5) bedded-deposits, and (6) gossan-deposits. The iron-ores are further distinguished under two classes available and not available. This classification is in large measure arbitrary, and it, is evident that it will vary front time to time. In the available class are placed those ores which can be worked at a profit under conditions essentially as they exist at present. Since it depends wholly on the question of costs, the various factors which affect cost will determine the classification of any particular deposit. Actual production, * Abstract of Report prepared for the Conservation Commission. t Chief Geologist, United States Geological Survey. .

Apr 1, 1909

By Burk, Hugh A.

AT THE inception of the cyanide process and its adaptation to the practice of gold and silver metallurgy much difficulty was experienced in applying it to auro-cupriferous ores, both in economy of treatment and recovery of the gold from solution. The presence of copper in the ore effected a high chemical consumption of cyanide during treatment, and in the solvent solution, it retarded the precipitation of the gold on zinc shavings. The coating of the copper on the zinc shavings presented even worse difficulties than the increased cyanide consumption as most ores contain a small amount of copper. This interference of copper led to the use of other precipitating methods and attempts to recover the cyanide which was consumed during ore treatment. Of the other methods used, electrolytic precipitation was the most practical until a better understanding of the application of zinc shavings and zinc dust developed. In September, 1905, a patent entitled, "Method for Recovering Precious Metals from Solution," was granted to Isaac Anderson and Michael Scanton. This method is adaptable to precious metal ores containing a small percentage of copper but has never been extensively used or perfected. The process has

Jan 1, 1925