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At least 1,153 records · Page 64Linked to original sources
USGS1884

Report of the United States Geological Survey of the Territories Volume III: The vertebrata of the tertiary formations of the West Book I

I send herewith a report on the Tertiary Faunae of the United States as represented by collections made in various Territories and States west of the Mississippi River, embraced within the boundaries of your survey. The explorations from which the collections have been derived cover portions of the States and Territories included between British America on the north, the western boundaries of Minnesota and Missouri on the east; the northern borders of the Indian Territory and Arizona, and the middle of New Mexico on the south; and the Sierra Nevada on the west. The amount of material which I have procured through these explorations is large, and is but partially represented in the following pages. I trust that you will find the results a useful contribution to the records of your Geological Survey and to the science to which you have devoted your life ; and that you may find in this report some compensation for the arduous official duties which have recently withdrawn you to some degree from your chosen field of research.

Report↗
USGS1998

Carolina slate belt gold deposits in Virginia, North Carolina, South Carolina, and Georgia

The Southeastern United States, in particular, the Carolina slate belt of Virginia, North Carolina, South Carolina, and Georgia, has been an important region of mineral production (fig. 1). This region is thought to have major potential for containing large undiscovered deposits of gold and silver, as well as copper, lead, zinc, molybdenum, and tin. Gold production from the major mines (Haile, Brewer, Ridgeway, and Barite Hill) in South Carolina ranked sixth in the Nation in 1992. Despite the closing of all but one mine in 1997, the region continues to attract intense scrutiny by the mining industry. Current U.S. Geological Survey (USGS) efforts in the slate belt are led by a multidisciplinary team focused on an integrated, multistate, and multiyear project that has the potential to result in a fundamental reinterpretation of the economic geology of the region. The slate belt is considered a scientific frontier because of the rapid pace of data acquisition by the USGS, academia, and private sector geologists and because emerging concepts of its geologic evolution are controversial. Establishing the origin of the gold deposits is important, not only in guiding exploration, but for more accurate assessment of the potential for the occurrence of new deposits throughout the southern Appalachians. These efforts may result in further industry exploration that may lead to discovery of new economically viable mineral deposits, which would have a broad economic impact on the region. Another goal is to find ways to prevent human activities related to gold extraction from remobilizing toxic metals found in these deposits, which could have potential harmful effects on the environment.

Georgia, North Carolina, South Carolina, Virginia↗
USGS1959

Geology of the Lake Mary quadrangle, Iron County, Michigan

The Lake Mary quadrangle is in eastern Iron County, in the west part of the Upper Peninsula of Michigan. The quadrangle is underlain by Lower and Middle Precambrian rocks, formerly designated Archean and Algonkian rocks, and is extensively covered by Pleistocene glacial deposits. A few Upper Precambrian (Keweenawan) diabase dikes and two remnants of sandstone and dolomite of early Paleozoic age are also found in the area. The major structural feature is the Holmes Lake anticline, the axis of which strikes northwest through the northeast part of the quadrangle. Most of the quadrangle, therefore, is underlain by rock of the west limb of the anticline. To the northwest along the fold axis, the Holmes Lake anticline is separated from the Amasa oval by a saddle of transverse folds in the vicinity of Michigamme Mountain in the Kiernan quadrangle. The Lower Precambrian rocks are represented by the Dickinson group and by porphyritic red granite whose relation to the Dickinson group is uncertain, but which may be older. The rocks of the Dickinson group are chiefly green to black metavolcanic schist and red felsite, some of the latter metarhyolite. The dark schist is commonly magnetic. The Dickinson group underlies the core area of the Holmes Lake anticline, which is flanked by steeply dipping Middle Precambrian formations of the Animikie series. A major unconformity separates the Lower Precambrian rocks from the overlying Middle Precambrian rocks. In ascending order the formations of the Middle Precambrian are the Randville dolomite, the Hemlock formation, which includes the Mansfield iron-bearing slate member, and the Michigamme slate. An unconformity occurs between the Hemlock formation and Michigamme slate. The post-Hemlock unconformity is thought to be represented in the Lake Mary quadrangle by the absence of iron-formation of the Amasa formation, which is known to lie between the Hemlock and the Michigamme to the northwest of the Lake Mary quadrangle in the Crystal Falls quadrangle. Post-Hemlock erosion may account also for the absence of iron-formation of the Fence River formation on the east limb of the Holmes Lake anticline within the Lake Mary quadrangle. The Randville dolomite is not exposed and is known only from diamond drilling in the northeast part of the area where it occurs in the east and west limbs of the Holmes Lake anticline. The formation has a maximum thickness of about 2,100 feet; this includes a lower arkosic phase, some of which is quartz pebble conglomerate, a medial dolomitic phase, and an upper slate phase. The triad is gradational. Included within the formation are a few beds of chloritic schist thought to be of volcanic origin. An unconformity between the Randville and the succeeding Hemlock is not indicated in the quadrangle, but is probably present. The Hemlock formation is best exposed in the northwest and south-central parts of the area. The apparent thickness of the formation is 10,000- 17,000 feet. It is composed mainly of mafic metavolcanic rocks and intercalated slate and iron-formation. In the north part of the quadrangle the volcanic rocks are greenstone, which includes altered basaltic flow rocks, volcanic breccia, tuff, and slate. Pillow structures are common in the metabasalt. It is not certain if any Hemlock rocks are present in the east limb of the Holmes Lake anticline. In the south part of the quadrangle, the rocks of the Hemlock are chiefly chlorite and hornblende schist and hornfels. Pyroxene hornfels is sparingly present. At least two sedimentary slate belts are included in the Hemlock formation. One of these, the Mansfield iron-bearing slate member, includes in its upper part an altered chert-siderite iron-formation 30 to over 150 feet thick from which iron ore has been mined at the Mansfield location. The position of the iron-bearing rocks has been determined magnetically, and past explorations for iron ore are discussed. Though probably; unconformable, the contact between the Hemlock and the Michigamme formations appears conformable. The Michigamme slate consists of at least 4,000 feet of interbedded mica schist and granulite, the altered equivalents of the slate and graywacke characteristic of the Michigamme in adjacent areas. The Michigamme rocks are best exposed in the south part of the quadrangle in the vicinity of Peavy Pond. Two periods of regional metamorphism have resulted in the alteration of almost all of the rocks of the quadrangle. The Lower Precambrian rocks underwent at least one period of metamorphism, uplift, and erosion before the deposition of the Randville dolomite. After the deposition of the Michigamme slate, a post-Middle Precambrian period of regional metamorphism occurred with attending deformation and igneous intrusion. The grade of metamorphism rises toward the south in the area. The rocks in the northern two-thirds of the quadrangle are representative of greenschist facies of regional metamorphism, whereas the rocks in the southern onethird of the quadrangle are representative of the albite-epidote-amphibolite, the amphibolite, and the pyroxene hornfels facies, the metamorphic node centering about the intrusive Peavy Pond complex in the Peavy Pond area. The Precambrian sedimentary and volcanic rocks are cut by intrusive igneous rocks of different types and several different ages. Gabbroic sills and dikes invaded the Hemlock rocks at some time after the Hemlock was deposited and before the post-Middle Precambrian orogeny and metamorphism. Some contact metamorphism attended the intrusion of the major sills. One of the sills, the West Kiernan sill, is well differentiated. A syntectonic igneous body, composed of gabbro and minor ultramafic parts and fringed with intermediate and felsic differentiates and hybrids, the Peavy; Pond complex, was intruded into the Hemlock and Michigamme formations during the post-Middle Precambrian orogeny. The complex is situated in the Peavy Pond area at the crest of the regional metamorphic node. Contact-altered sedimentary and volcanic rocks margin the complex. The effects of regional metamorphism have been superposed on the contact metamorphic rocks peripheral to the complex and on the igneous rocks of the complex as well. The mafic augite-bearing rocks of the complex emplaced early in the orogeny were deformed by granulation at the peak of the deformation and subsequently metamorphosed to hornblende rocks. Some of the intermediate and felsic rocks of the complex were foliated by the deformation, while the more fluid, felsic parts of the complex were intruded under orogenic stress and crystallized after the peak of deformation. The deformation culminated in major faulting during which the formations were dislocated, and some of the granite of the complex was extremely brecciated. A few diabase dikes, probably of Keweenawan age, have intruded the deformed and altered Animikie rocks. The only known metallic resource is iron ore. The Mansfield mine produced 1¥2 million tons of high-grade iron ore between the years 1890 and 1913. Sporadic exploration since 1913 has failed to reveal other ore deposits of economic importance.

Michigan↗
USGS1992

Bedrock geology and mineral resources of the Knoxville 1° x 2° quadrangle, Tennessee, North Carolina, and South Carolina

The Knoxville 1° x 2° quadrangle spans the Southern Blue Ridge physiographic province at its widest point from eastern Tennessee across western North Carolina to the northwest corner of South Carolina. The quadrangle also contains small parts of the Valley and Ridge province in Tennessee and the Piedmont province in North and South Carolina. Bedrock in the Valley and Ridge consists of unmetamorphosed, folded and thrust-faulted Paleozoic miogeoclinal sedimentary rocks ranging in age from Cambrian to Mississippian. The Blue Ridge is a complex of stacked thrust sheets divided into three parts: (1) a west flank underlain by rocks of the Late Proterozoic and Early Cambrian Chilhowee Group and slightly metamorphosed Late Proterozoic Ocoee Supergroup west of the Greenbrier fault; (2) a central part containing crystalline basement of Middle Proterozoic age (Grenville), Ocoee Supergroup rocks east of the Greenbrier fault, and rocks of the Murphy belt; and (3) an east flank containing the Helen, Tallulah Falls, and Richard Russell thrust sheets and the amphibolitic basement complex. All of the east flank thrust sheets contain polydeformed and metamorphosed sedimentary and igneous rocks of mostly Proterozoic age. The Blue Ridge is separated by the Brevard fault zone from a large area of rocks of the Inner Piedmont to the east, which contains the Six Mile thrust sheet and the ChaugaWalhalla thrust complex. All of these rocks are also polydeformed and metamorphosed sedimentary and igneous rocks. The Inner Piedmont rocks in this area occupy both the Piedmont and part of the Blue Ridge physiographic provinces. The intensity of deformation and metamorphism increases from west to east in the Blue Ridge. The west flank is mostly chlorite grade or relatively unmetamorphosed, and the central part of the Blue Ridge is mostly staurolite, garnet, or biotite grade, although sillimanite grade rocks occur along the eastern part of the central Blue Ridge in the vicinity of the leading edge of the Hayesville fault. The east flank of the Blue Ridge and much of the Inner Piedmont are at kyanite or sillimanite grade of regional metamorphism except for a zone of retrograde rocks in the Brevard fault zone and a small area of biotite-grade rocks in the extreme southwest part of the Grandfather Mountain window in the northeast corner of the quadrangle. The major mineral resources in the Knoxville 1° x 2° quadrangle are construction materials and a variety of industrial minerals mostly related to either granite and pegmatite or ultramafic rocks. Past production in the quadrangle of metals, which are of secondary importance relative to construction materials and industrial minerals, include copper in massive sulfides of the Besshi type, gold-bearing quartz veins, and residual iron and manganese deposits. Resources are discussed in relation to the Valley and Ridge, Blue Ridge, and Piedmont provinces. The following resources are the most important: A. Construction materials: Dimension stone of the Tennessee marble district in the Valley and Ridge. Limestone and dolomite of the Valley and Ridge. Sand and gravel and crushed stone, widespread throughout the quadrangle. B. Industrial minerals: Feldspar, flake mica, and quartz produced by flotation methods from the Spruce Pine Alaskite (muscovite granodiorite) in the east flank of the Blue Ridge. The district produces about half of the U.S. feldspar and significant amounts of the U.S. flake mica. Olivine produced from alpine-type dunite bodies in the east flank of the Blue Ridge. Talc and marble from the Murphy belt in the central part of the Blue Ridge. Vermiculite produced from a large deposit near Tigerville, S.C., in the Inner Piedmont. Deposit worked out and mine backfilled. Smaller deposits associated with ultramafic rocks in the east flank of the Blue Ridge are now uneconomic and have not been worked in the past 20 years. C. Metals: Copper in three deposits, the Fontana and Hazel Creek mines in the Great Smoky Mountains National Park in the Central Blue Ridge, and the Cullowhee mine in the east flank of the Blue Ridge. D. Organic fuels: The rocks of the quadrangle contain no coal and probably lie outside the maximum range in thermal maturity permitting the survival of oil. The rocks in the Valley and Ridge and for a short distance eastward below the west flank of the Blue Ridge probably lie within a zone of thermal maturity permitting the survival of natural gas. Consequently the western part of the quadrangle is an area of high risk for hydrocarbon exploration. No exploration drilling has been done in this belt.

North Carolina, South Carolina, Tennessee↗
USGS2007

Regional Studies of the Potwar Plateau Area, Northern Pakistan

The papers in this volume are products of a cooperative program between the Geological Survey of Pakistan (GSP) and the U.S. Geological Survey (USGS), sponsored by the Government of Pakistan and the U.S. Agency for International Development. The focus of the program, the Coal Resources Exploration and Assessment Program (COALREAP), was to explore and assess Pakistan?s indigenous coal resources. As part of COALREAP, GSP and USGS geologists conducted regional geologic studies from 1988 to 1991 of the coal-bearing areas in the Potwar region of northern Pakistan. A reference section was selected from which to obtain faunal and floral analyses. The composite sections at Nammal Pass and Nammal Dam served as the basis for this regional reference. Although this Bulletin 2078 is being released in 2007, the writing and technical reviews were completed in 1993, and the chapters reflect the work done until that time. During the long production process for the Bulletin, which ultimately resulted in the oversize plates being digitized, the scientific content of the chapters was not changed, and most reports published since 1993 were not cited. A change in the age of the Patala Formation is discussed below [in the full preface], but the age discussions and illustrations in the chapters were not updated.

Bulletin↗
USGS1999

Ghaba salt basin province and Fahud salt basin province, Oman; geological overview and total petroleum systems

Three Total Petroleum Systems each consisting of one assessment unit have been identified in the Ghaba and Fahud Salt Basin Provinces of north-central Oman. One Total Petroleum System and corresponding assessment unit, the North Oman Huqf/?Q??Haushi(!) Total Petroleum System (201401) and Ghaba- Makarem Combined Structural Assessment Unit (20140101), were identified for the Ghaba Salt Basin Province (2014). In the Fahud Salt Basin Province, however, two overlapping Total Petroleum Systems (TPS) were recognized: (1) the North Oman Huqf?Shu?aiba(!) TPS (201601); Fahud-Huqf Combined Structural Assessment Unit (20160101), and (2) the middle Cretaceous Natih(!) TPS (201602); Natih-Fiqa Structural/Stratigraphic Assessment Unit (20160201). The boundary for each Total Petroleum System also defines the boundary of the corresponding assessment unit and includes all trap styles and hydrocarbon-producing reservoirs within the petroleum system. In both the Ghaba and Fahud Salt Basin Provinces, hydrocarbons were generated from several deeply buried source rocks within the Infracambrian Huqf Supergroup. One general ?North Oman Huqf? type oil is dominant in the Fahud Salt Basin. Oils in the Ghaba Salt Basin are linked to at least two distinct Huqf source-rock units based on oil geochemistry: a general North Oman Huqf-type oil source and a more dominant ?questionable unidentified source? or ?Q?-type Huqf oil source. These two Huqf-sourced oils are commonly found as admixtures in reservoirs throughout northcentral Oman. Hydrocarbons generated from Huqf sources are produced from a variety of reservoir types and ages ranging from Precambrian to Cretaceous in both the Ghaba and Fahud Salt Basin Provinces. Clastic reservoirs of the Gharif and Al Khlata Formations, Haushi Group (middle Carboniferous to Lower Permian), dominate oil production in the Ghaba Salt Basin Province and form the basis for the Huqf/?Q??Haushi(!) TPS. In contrast, the Lower Cretaceous Shu?aiba and middle Cretaceous Natih limestones account for most of the production in the Fahud Salt Basin with about 50 percent of the basin?s production from porous, fractured Shu?aiba limestones in Yibal field, thus the name North Oman Huqf? Shu?aiba(!) TPS. Deep gas is produced mainly from Middle Cambrian to Lower Ordovician clastic reservoirs of the Haima Supergroup. Traps in nearly all hydrocarbon accumulations of these petroleum systems are mainly structural and were formed by one or more 3 mechanisms. These trap-forming mechanisms were mainly periodic halokinesis of the thick Cambrian Ara Salt and consequent folding and faulting from basin loading, rifting, or other major tectonic events, particularly those events forming the Oman Mountains and associated foreland-basin system during the Late Cretaceous and late Tertiary. Many of the future new-field targets will likely be low-relief, subtle structures, as many of the large structures have been drilled. Oman?s recent interest and commitments to liquid natural gas export make deep gas a primary objective in the two North Oman Huqf petroleum systems. New-field exploration of deep gas and exploring deeper targets for gas in existing fields will likely identify a significant gas resource in the next 30 years. Moreover, salt-diapir flank traps in these two North Oman Huqf petroleum systems and salt basin provinces have gone essentially untested and will likely be targeted in the near future. The middle Cretaceous Natih(!) TPS is a small efficient system of the Fahud Salt Basin. Natih source rocks are only mature in the Late Cretaceous/Tertiary foredeep and production is primarily from Natih reservoirs; minor production from the Shu?aiba limestone is documented along fault-dip structures. Most traps are structural and are related to development of the foreland basin and formation of the Oman Mountains. Future targets of the Natih TPS will be less obvious

Bulletin↗
USGS2000

Organic metamorphism in the California petroleum basins; Chapter B, Insights from extractable bitumen and saturated hydrocarbons

Seventy-five shales from the Los Angeles, Ventura, and Southern San Joaquin Valley Basins were extracted and analyzed. Samples were chosen on the basis of ROCK-EVAL analyses of a much larger sample base. The samples ranged in burial temperatures from 40 ? to 220 ? C, and contained hydrogen-poor to hydrogen-rich organic matter (OM), based on OM visual typing and a correlation of elemental kerogen hydrogen to carbon ratios with ROCK-EVAL hydrogen indices. By extractable bitumen measurements, rocks with hydrogen- poor OM in the Los Angeles Basin began mainstage hydrocarbon (HC) generation by 90 ? C. The HC concentrations maximized by 165 ? C, and beyond 165 ? C, HC and bitumen concentrations and ROCK-EVAL hydrogen indices all began decreasing to low values reached by 220 ? C, where HC generation was largely complete. Rocks with hydrogen-poor OM in the Southern San Joaquin Valley Basin commenced mainstage HC generation at 135 ? C and HC concentrations maximized by 180 ? C. Above 180 ? C, HC and bitumen concentrations and ROCK-EVAL hydrogen indices all decreased to low values reached by 214 ? C, again the process of HC generation being largely complete. In both cases, bell-shaped HC-generation curves were present versus depth (burial temperature). Mainstage HC generation had not yet begun in Ventura Basin rocks with hydrogen-poor OM by 140 ? C. The apparent lower temperature for initiation of mainstage generation in the Los Angeles Basin is attributed to very recent cooling in that basin from meteoric-water flow. Thus, HC generation there most probably occurred at higher burial temperatures. In contrast, mainstage HC generation, and all aspects of organic metamorphism, were strongly suppressed in rocks with hydrogen-rich OM at temperatures as high as 198 ? C. For example, shales from the Wilmington field (Los Angeles Basin) from 180 ? to 198 ? C retained ROCK-EVAL hydrogen indices of 550- 700 and had saturated-HC coefficients of only 4-15 mg/g organic carbon. The rocks with hydrogen-rich OM were subjected to the same burial conditions as the rocks with hydrogenpoor OM. We attribute this suppression of organic metamorphism in this study primarily to much stronger bonds in the hydrogen-rich OM compared to the bonds in hydrogen-poor OM. Trends in bitumen compositions (qualitative characteristics) versus burial temperature were also very different for rocks with hydrogen-poor OM compared to that in rocks with hydrogen- rich OM. This observation demonstrated that the two OM types also had significantly different reaction pathways, in addition to different reaction kinetics. Strong exploration implications arise from these observations. Above 40?C, but before mainstage HC generation, a lowtemperature (pre-mainstage) HC generation occurred in all rocks, and all OM types, studied. This low-temperature generation resulted in significant qualitative changes in the bitumen and HCS (hydrocarbons) from rocks of all OM types, especially in rocks with hydrogen-rich OM, from 40 ? to 70 ? C. This, and previous studies, document that very high carbon-normalized concentrations of indigenous bitumen and HCS occur in late Neogene immature rocks of any OM type in all southern California basins. This characteristic is attributed to the low-temperature generation occurring in both sulfur-poor and sulfur-rich kerogens, which originally had unusually high concentrations of weak (15-40 Kcal/mole) bonds. These observations and considerations have marked relevance to exploration regarding the possible formation of commercial oil deposits at immature ranks in these basins. Other significant geochemical observations also result from this study.

Bulletin↗
USGS2001

Petroleum geology and resources of the Baykit High province, East Siberia, Russia

The Baykit High province consists of two principal structural units?the Baykit regional high in the west, which occupies most of the province, and the Katanga structural saddle in the east. The province is on the western margin of the Siberian craton east of theYenisey Ridge foldbelt. The province is an exploration frontier and only a few prospects have been drilled. The oldest sedimentary rocks of the province, Riphean carbonate and clastic strata of Late Proterozoic age (1,650?650 million years old) that were deposited on the passive margin, cover the Archean?Lower Proterozoic basement. Basal Vendian (uppermost Proterozoic, 650?570 million years old) clastic rocks unconformably overlie various units of the Riphean and locally lie directly on the basement. Younger Vendian and lowermost Cambrian rocks are primarily dolomites. The Vendian/Cambrian boundary is con-formable, and its exact stratigraphic position has not been identified with certainty. The Lower Cambrian section is thick, and it consists of alternating beds of dolomite and evaporites (mostly salt). Middle and Upper Cambrian strata are composed of shale and dolomite. Ordovician-Silurian and upper Paleozoic rocks are thin, and they are present only in the northern areas of the province. Structural pattern of Riphean rocks differs substantially from that of Vendian-Cambrian rocks. A single total petroleum system (TPS) was identified in the Baykit High province. Discovered oil of the system is chiefly concentrated in Riphean carbonate reservoirs of the Yurubchen-Tokhom zone that is currently being explored and that has the Abstract 1 potential to become a giant field (or group of fields). The TPS also contains about 5 trillion cubic feet of discovered recover-able gas in clastic reservoir rocks at the base of the Vendian section. Petroleum source rocks are absent in the stratigraphic succession over most of the TPS area. Riphean organic-rich shales and carbonates that crop out in the Yenisey Ridge foldbelt west of the Baykit high are probable source rocks. Their areal distribution extends from the foldbelt into the foredeep along the province?s western margin. Potential source rocks also are present in platform depressions in eastern areas of the province. Hydrocarbon generation and migration west of the province started as early as Riphean time, before the beginning of the deformation in the Yenisey Ridge foldbelt that occurred about 820?850 million years ago. However, the presently known oil and gas accumulations were formed after deposition of the Lower Cambrian salt seal. Available data allow identification of only one assessment unit, and it covers the entire TPS area. Undiscovered oil and gas resources are moderate, primarily due to the poor quality of reservoir rocks. However, the reserve growth in the Yurubchen-Tokhom zone may be large and may exceed the volume of undiscovered resources in the rest of the province. Most oil and gas resourcesareexpectedtobeinstructuralandstratigraphictrapsin Riphean carbonate reservoirs. Vendian clastic reservoirs are probably gas-prone.

Bulletin↗
USGS1914

The Glacier National Park: A popular guide to its geology and scenery

The Glacier National Park includes that part of the Front Range of the Rocky Mountains lying just south of the Canadian line, in Teton and Flathead counties, Mont. It is bounded on the west by Flathead River (locally called North Fork), on the south by the Middle Fork of Flathead River and the Great Northern Railway, and on the east by the Blackfeet Indian Reservation. Although this part of the Rocky Mountains has been known since Lewis and Clark crossed the continent in 1805-6, the region later made a park appears not to have been visited by white men until 1853, when Cut Bank Pass was crossed by A. W. Tinkham, one of the Government engineers engaged in exploring a route for the Pacific railroad. Tinkham, who was encamped in the Bitterroot Valley, was ordered to examine Marias Pass, but in traversing Middle Fork of Flathead River along the line of the present railroad he was evidently misled by the large size of the valley of Nyack Creek and ascended that instead of keeping to the right up the main stream. He reported the pass impracticable for railroad construction, and so this region dropped out of public attention for a long time. The next explorers to enter the region were a group of surveyors who, under the direction of American and British commissioners, established the international boundary line along the forty-ninth parallel from the Pacific coast to the main summit of the Rocky Mountains. This party reached the area now included in the park in the summer of 1861, and the stone monument shown in Plate I, B, which they erected on the Continental Divide west of Waterton Lake, still marks a point on the boundary between the United States and Canada. The land on the west side of the range formed a part of the public domain which, until the erection of the park, was open to settlement, but the land on the east originally belonged to the Blackfeet Indians and the white men had no rights upon it. About 1890 copper ore was found near the heads of Quartz and Mineral creeks, and a great boom for this region followed. Many prospectors drifted in, expecting to reap rich rewards from the discovery of mineral deposits and the general development of the region. Several of the main trails were built about this time, and considerable money was spent in prospecting, in opening mines, and in providing machinery to handle the large output of copper ore that was expected. The copper-bearing veins were found to extend through the range to the east side, but prospecting in that part of the mountains was not possible, for the land was included in the Indian reservation. This situation produced a growing discontent among the prospectors, who began to have a strong feeling that the Government should come to their relief by acquiring the coveted land and placing it at their disposal. The urgent demand of the prospectors and promoters was felt in Congress, and a bill was passed providing for the purchase from the Indians of this supposed mineral land for $1,500,000. In accordance with this act, a treaty with the Blackfeet Indians was signed at Browning, Mont., September 26, 1895, and approved by the Senate on June 10, 1896, by which the west line of the reservation was removed from the Continental Divide and was fixed along the eastern points of the spurs of the mountain range, as shown on the accompanying map, and the land so acquired was thrown open to mineral entry only. Under the stimulus of the new territory acquired, active prospecting was carried on for a time, but copper ore was found only in small quantities, and gradually the prospectors and miners drifted away to newer or more promising fields, and the region reverted to its original condition. For a long time it was visited only by hunters in search of big game and by summer visitors who, in order to escape the heat of the plains, were willing to undergo the privations and discomforts of the rude hotels then to be found in the region. Although these mountains had ceased to interest prospectors in search of mineral wealth, they still possessed a fascination for the lovers of natural scenery and almost everyone who visited the region was impressed with its alpine beauty. Again it was brought to the attention of Congress, which was urged to secure it for the use of the people by setting it aside as a national park. On May 11, 1910, President Taft signed the bill creating the Glacier National Park, and this most interesting and beautiful region thus became a permanent playground for the American people.

Bulletin↗
USGS1944

Manganese Deposits in the Artillery Mountains Region, Mohave County, Arizona

The manganese deposits of the Artillery Mountains region lie within an area of about 25 square miles between the Artillery and Rawhide Mountains, on the west side of the Bill Williams River in west-central Arizona. The richest croppings are on the northeast side of this area, among the foothills of the Artillery Mountains. They are 6 to 10 miles from Alamo. The nearest shipping points are Congress, about 50 miles to the east, and Aguila, about 50 miles to the southeast. The principal manganese deposits are part of a sequence of alluvial fan and playa material, probably of early Pliocene age, which were laid down in a fault basin. They are overlain by later Pliocene (?) basalt flows and sediments and by Quaternary basalt and alluvium. The Pliocene (?) rocks are folded into a shallow composite S1ncline ttat occupies the valley between the Artillery and Rawhide Mountains, and the folded rocks along either side of the valley, together with the overlying Quaternary basalt, are broken by faults that have produced a group of horsts, grabens, and step-fault blocks. The manganiferous beds, lie at two zones, 750 to 1,000 feet apart stratigraphically, each of which is locally as much as 300 to 400 feet thick. The main, or upper, zone contains three kinds of ore - sandstone ore, clay ore, and 'hard' ore. The sandstone and clay ores differ from the associated barren sandstone and clay, with which they are interlayered and into which they grade, primarily in containing a variable proportion of amorphous manganese oxides, besides iron oxides and clayey material such as are present in the barren beds. The 'hard' ore is sandstone that has been impregnated with opal and calcite and in which the original amorphous manganese oxides have been largely converted to psilomelane and manganite. The average manganese content of the sandstone and clay ores is between 3 and 4 percent and that of the 'hard' ore is between 6 and 7 percent. The ore contains an average of 3 percent of iron, 0.08 percent of phosphorus, 1.1 percent of barium, and minute quantities of copper, lead, and zinc. Although the manganese content of the sandstone and clay ore may change abruptly from bed to bed, the content within any individual bed changes gradually, and for any large volume of ore both the nanganese and iron content are remarkably uniform. Explorations to June 1941 consisted chiefly of 49 holes diamond-drilled in the upper zone on the Artillery Mountains side of the area. The district is estimated to contain an assured minimum of 200,000,000 tons of material having an average manganese content of 3 to 4 percent. About 20,000,000 tons of this total contains 5 percent or more of manganese, and 2,000,000 to 3,000,000 tons contains 10 percent or more. To what extent these deposits can be utilized is a metallurgical and economic problem. Although the clay and sandstone ores, as well as the 'hard' ore, are present in large tonnages, the 'hard' ore is the only kind that combines minable tonnage with promising grade. About 15,000,000 tons of 'hard' ore is present; about 500,000 tons of this contains 15 percent or more of manganese and averages 17 percent, and somewhat over 2,000,000 tons contains 10 percent or more and averages nearly 13 percent. Except for closer drilling to determine such things as the tonnage, grade, spacing, and form of the richer shoots with greater accuracy before beginning to mine them, further explorations are not recommended, for any new ore found is likely to be similar, both in grade and kind, to that already discovered.

Arizona↗
USGS2009

History of the topographic branch (division)

From a very early period of the world's existence, man has endeavored to represent the earth's surface in a graphic form for the information of his fellow men, realizing that no oral or written description is capable of setting forth topographic facts so vividly and so clearly as a map. Mapping of the areas of the United States began with the charting of portions of its coast line by early explorers; the need for topographic maps was first recognized during the war of the Colonies for independence from Great Britain. On July 22, 1777, Congress authorized General Washington to appoint: 'Mr. Robert Erskine, or any other person that he may think proper, geographer and surveyor of the roads, to take sketches of the country and the seat of war.' By several acts during the Revolutionary War, Congress provided 'geographers' for the armies of the United States, some of them with the pay of a colonel, amounting to $60 a month and allowances. At the end of the War, a resolution of May 27, 1785, continued in service the 'geographer of the United States' for a period of 3 years. The War Department recognized the necessity of 'geographical engineers' and requested Congress to authorize their appointment, but it was not until the next war that Congress authorized on March 3, 1813, the appointment of eight topographic engineers and eight assistant topographic engineers under the direction of the General Staff of the Army. These officers formed the nucleus of the first Corps of Topographic Engineers in the Army, and that Corps continued to function as an independent unit until it was absorbed by the Corps of Engineers in 1863, during the Civil War between the States. Between the Louisiana Purchase in 1803, and the outbreak of the Civil War, more than a hundred exploring and mapping expeditions were sent into the vast territory lying west of the Mississippi River to investigate the natural resources of this newly acquired country and to find possible locations for wagon roads to the Pacific Coast. These expeditions were sent out by the War Department and were in charge of Army officers. It is interesting to note that such generals as George G. Meade, J.C. Fremont, Joseph E. Johnston, W.F. Smith, John Pope, A.W. Whipple, J.G. Parke, G.K. Warren, and H.L. Abbott, all officers of the Corps of Topographic Engineers, had charge of expeditions and were among our earliest map makers. Unfortunately, the data obtained by these editions were not of sufficient accuracy to serve as a basis for topographic maps of value other than in illustrating their voluminous reports. During this early period, numerous surveys were undertaken within the original Thirteen States, by the Federal government and by the States. The most important were those carried on by the U.S. Coast and Geodetic Survey, which made an accurate survey of the Atlantic Coastline and established a triangulation system that was of so high a standard as to constitute the first and only accurate data for topographic mapping obtained before the Civil War. The Coast and Geodetic Survey, while charting the coast and rivers, also mapped a strip of country extending a few miles inland, the relief being shown by means of hachures, together with contour lines, until 1846 when the first government topographic map on which the relief was shown by contours alone was made, covering an area in the vicinity of Boston Harbor. In 1835, however, the Geological and Topographical Survey of Maryland had issued a map on which the relief was shown by contours, and this is believed to be the first contoured map issued in this country. The outbreak of the Civil War stopped all mapping activities other than those needed by the U.S. Army. During the war, topographic surveys were carried on throughout the war zone under the supervision of the Corps of Engineers, the topographers being civilian employees. After the war, the country west of the Mississippi again became the center of the mapping activities

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USGS2013

Challenge theme 5: Current and future needs of energy and mineral resources in the Borderlands and the effects of their development: Chapter 7 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science

Exploration and extraction activities related to energy and mineral resources in the Borderlands—such as coal-fired power plants, offshore drilling, and mining—can create issues that have potentially major economic and environmental implications. Resource assessments and development projects, environmental studies, and other related evaluations help to understand some of these issues, such as power plant emissions and the erosion/denudation of abandoned mine lands. Information from predictive modeling, monitoring, and environmental assessments are necessary to understand the full effects of energy and mineral exploration, development, and utilization. The exploitation of these resources can negatively affect human health and the environment, its natural resources, and its ecological services (air, water, soil, recreation, wildlife, etc.). This chapter describes the major energy and mineral issues of the Borderlands and how geologic frameworks, integrated interdisciplinary (geobiologic) investigations, and other related studies can address the anticipated increases in demands on natural resources in the region.

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USGS1953

Monazite deposits of the southeastern Atlantic States

Monazite, a phosphate of the rare earths, is the principal mineral from which the cerium earths and thorium are obtained. Fluviatile monazite placers were mined in the Piedmont province of North and South Carolina from 1887 to 1911, and again intermittently from 1915 to 1917; but the principal sources In recent years have been the beach placers of India and Brazil. In 1946, an embargo was placed on the exportation of Indian monazite, and the Brazilian production has not increased materially to replace this loss. Accordingly monazite in recent years has become a scarce commodity. The principal domestic sources from which monazite may be recovered commercially are in Idaho and in the Piedmont province of the southeastern States. Some monazite is now being produced in Idaho, and a small output is being recovered as a byproduct of heavy mineral mining in Florida. The southeastern placers were not exhausted by the earlier mining and new deposits have been discovered; but production from this region awaits adequate exploration. The country rock of the southeastern Piedmont province is a complex assemblage of metamorphic and igneous rocks. The monazite occurs in two belts. A western belt has been traced from east-central Virginia for 600 miles southwestward into Alabama; and an eastern belt has been traced from the vicinity of Fredericksburg, Va., south-southwestward for 200 miles into North Carolina. Monazite-bearing rocks near. Rion, S. C., appear to indicate a southwestward continuation of the eastern belt. The western, or principal belt, includes the placers that were formerly mined in North and South Carolina. These placers were sampled, and the monazite was separated from the best of the samples, for mineralogical and chemical analysis. The tabulated results show a mean tenor, in the headwater placers of highest grade, of 8.4 pounds of monazite to the cubic yard. Farther downstream where mining must be done to obtain larger yardages, the tenor will be much lower. The mean contents of ThO2 and U3O8 in the placer monazite are shown to be respectively about 5. 7 and 0.4 percents. The western monazite belt was explored northeastward and southwestward from the sites of earlier mining by sampling the weathered bedrock; and the eastern monazite belt was discovered and sampled by the same technique. The principal source-rocks are certain types of granitic intrusives, granitized and pegmatitized country rock, and certain granitic gneisses of the Carolina gneiss. Some of the associated pegmatites also contain high percentages of monazite. Most of the monazite-bearing granitic intrusives are quartz monzonite or closely related rocks. The mean tenor of monazite in bedrock is about 0.006 percent. No search has yet been made for workable placers in these belts beyond the original sites of mining. Monazite derived from bedrock sources in the piedmont has been found in small quantities in all of the Coastal Plain formations, but the tenor is too low to warrant mining for this mineral alone. At favored localities, however, commercial deposits of heavy minerals may be found, similar to those now being mined in Florida, that may yield monazite as a byproduct. Small fluviatile deposits of heavy minerals, including monazite, that were reconcentrated from detrital deposits of Cretaceous age, have recently been found in Georgia and South Carolina, along the inner margin of the Coastal Plain. The monazite belts are conceived to be the sites of early pre-Cambrian valleys, wherein detrital monazite derived from an earlier pre-Cambrian granite, was distributed. These ancient fluviatile deposits were later reconstituted into gneisses of Carolina age, and parts of the latter were remelted to form monazite-bearing granitic intrusives. Some of the monazite-bearing granites may also have originated by the remelting of earlier pre-Cambrian intrusives. The distribution of iron ores in the monazite-bearing rocks appears to accord with

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USGS1970

Elemental sulfur in Eddy County, New Mexico

Sulfur has been reported in Eddy County, N. Mex., in rocks ranging from Silurian to Holocene in age at depths of 0-15,020 feet. Targets of present exploration are Permian formations in the Delaware Basin and northwest shelf areas at depths of less than 4,000 feet. Most of the reported sulfur occurrences in the shelf area are in the 'Abo' (as used by some subsurface geologists), Yeso, and San Andres Formations and the Artesia Group. Sulfur deposition in the dense dolomites of the 'Abo,' Yeso, and San Andres Formations is attributed to the reduction of ionic sulfate by hydrogen sulfide in formation waters in zones of preexisting porosity and permeability. A similar origin accounts for most of the sulfur deposits in the formations of the Artesia Group, but some of the sulfur in these formations may have originated in place through the alteration of anhydrite to carbonate and sulfur by the metabolic processes of bacteria in the presence of hydrocarbons. Exploration in the Delaware Basin area is directed primarily toward the Castile Formation. Sulfur deposits in the Castile Formation are found in irregular masses of cavernous brecciated secondary carbonate rock enveloped by impermeable anhydrite. The carbonate masses, or 'castiles,' probably originated as collapse features resulting from subsurface solution and upward stopping. Formation of carbonate rock and sulfur in the castiles is attributed to the reduction of brecciated anhydrite by bacteria and hydrocarbons in the same process ascribed to the formation of carbonate and sulfur in the caprocks of salt domes.

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USGS1975

Mineral resource management of the Outer Continental Shelf : leasing procedures, evaluation of resources, and supervision of production operations on leased lands of the Outer Continental Shelf

An important function of the Geological Survey is the evaluation and management of the mineral resources of the Outer Continental Shelf, particularly with respect to oil and gas, salt, and sulfur. Production of oil and gas from the Outer Continental Shelf of the United States has increased substantially over the past 20 years and represents an increasing percentage of total United States production. As discovery of major onshore production of oil and gas has become more difficult, the search has moved into the surrounding waters where submerged sedimentary formations are conducive to the accumulation of oil and gas. Increased energy demands of recent years have accelerated the pace of offshore operations with a corresponding improvement in technology as exploration and development have proceeded farther from shore and into deeper water. While improved technology and enforcement of more stringent regulations have made offshore operations safer, it is unrealistic to believe that completely accident-free operations can ever be achieved. Only slightly more than six percent of the world's continental terrace is adjacent to the United States, but less than one percent has been explored for oil and gas. Since the lead time for the development of offshore oil and gas resources can be as much as a decade, they do not provide an immediate energy supply but should be viewed in the light of a near-term source with a potential of becoming a medium-range source of supply pending the development of alternative energy sources. Revenues from the Outer Continental Shelf are deposited to the general fund of the United States Treasury. A major portion of these funds is allocated to the Land and Water Conservation Fund, the largest Federal grant-in-aid program of assistance to States, counties, and cities for the acquisition and development of public parks, open space, and recreation lands and water.

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USGS1983

Assessment of undiscovered conventionally recoverable petroleum resources of Indonesia

The estimates of undiscovered conventionally recoverable petroleum in Indonesia at probability levels of 95 percent, 5 percent, and statistical mean are for oil (in billions of barrels): 5, 35, and 16; and for gas (in trillions of cubic feet): 13, 94, and 42. In Indonesia, petroleum occurs in five types of basins: forearc, back-arc (foreland), median, inner-arc, and downwarp into-small-ocean basins. The back-arc, median, and downwarp basins have significantly greater petroleum potential than do the fore-arc and inner-are basins. The latter two types are expected to yield only small discoveries; also, significant portions of such basins lie in water depths in excess of 1,000 m. The back-arc basins have been the most petroleum productive, but they also have been the most extensively explored. The greatest undiscovered petroleum potential is estimated to lie in the downwarp and median basins. In Indonesia, six general types of geological settings or plays have been identified as being favorable for petroleum accumulation. They are transgressive clastic sequences, regressive clastic sequences, deltas, carbonate platforms, pinnacle reefs, and fractured igneous and volcanic rocks. The multiple-pay transgressive clastic reservoirs in the back-arc basins have produced most of Indonesia's crude oil. In several basins, carbonate platform porosity has become a primary exploration target, but each reservoir (reef, bank, or bioclastic zone) tends to be restricted in size. Typically, Indonesian oil is of medium gravity with a paraffin base and has a moderate to high pour point, a low sulfur content, and a relatively low gas to oil ratio.

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USGS1983

Petroleum and mineral resources of Antarctica

No known petroleum or mineral resources occur in Antarctica. The data on these subjects have been collected, mainly since the IGY (International Geophysical Year), 1957-58, as a part of other research carried out by geologists and geophysicists from a number of countries. Specific resource-related studies have not been made. Wright and Williams (1974) summarized what was known of Antarctic mineral resources a decade ago. The U.S. Geological Survey has been actively pursuing various investigations in Antarctica since 194 7. In the course of this work and that of our colleagues elsewhere in the United States and in other countries, much information relevant to petroleum and mineral resources has been obtained. Since 1976, modern state-of-the-art multichannel seismic reflection and aeromagnetic surveys by several countries over the continental margin of Antarctica have indicated thick sedimentary basins. However, no offshore drilling beneath the continental shelf has taken place since the DSDP (Deep Sea Drilling Project) holes in the Ross Sea in 1973. Geologic field investigations begun at the turn of the twentieth century have been intensified in the past two decades; most rock outcrops have been visited and samples collected. Technology to exploit resources, particularly in the Arctic, has been developing at a rapid rate, and much of it could be applied to Antarctica. As a result of the petroleum price increases of the past decade, the attention of a number of countries has turned to Antarctica, but under the policy of "voluntary restraint" adopted by the Antarctic Treaty nations, no active petroleum or mineral exploration is taking place. The Antarctic treaty countries are in the process of negotiating an Antarctic mineral resources regime that is anticipated to be completed within the next several years. Therefore it seemed timely to us to readdress the question of petroleum and mineral resources. These reports review and summarize the available information. The first report summarizes the information relevant to petroleum resources. Although uneconomic at present, petroleum is generally considered more likely to be exploited (if supergiant fields were ever found) in the next few decades than hard minerals. The second report reviews the reported occurrences of minerals in Antarctica and discusses their significance. The final report discusses the Dufek layered mafic intrusion, second only to the Bushveld Complex in size in the world; the Dufek intrusion might be considered as a potential target for mineral exploration.

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USGS1985

Petroleum geology and resources of northeastern Mexico

Petroleum deposits (primarily gas) in northeastern Mexico occur in two main basins, the Tertiary Burgos basin and the Mesozoic Sabinas basin. About 90 gas fields are present in the Burgos basin, which has undergone active exploration for the past 30-40 years. Production in this basin is from Oligocene and Eocene nearshore marine and deltaic sandstone reservoirs. Most of the fields are small to medium in size on faulted anticlinal or domal structures, some of which may be related to deep-seated salt intrusion. Cumulative production from these fields is about 4 trillion cubic feet gas and 100 million barrels condensate and oil. Since 1975, about 10 gas fields, some with large production rates, have been discovered in Cretaceous carbonate and Jurassic sandstone reservoirs in the Sabinas basin and adjacent Burro-Picachos platform areas. The Sabinas basin, which is in the early stages of exploration and development, may have potential for very large gas reserves. The Sabinas basin is oriented northwesterly with a large number of elongate northwest- or west-trending asymmetric and overturned Laramide anticlines, most of which-are faulted. Some of the structures may be related to movement of Jurassic salt or gypsum. Lower Cretaceous and in some cases Jurassic rocks are exposed in the centers of the larger anticlines, and Upper Cretaceous rocks are exposed in much of the remainder of the basin. A thick section of Upper Cretaceous clastic rocks is partly exposed in tightly folded and thrust-faulted structures of the west-east oriented, deeply subsided Parras basin, which lies south of the Sabinas basin and north of the Sierra Madre Oriental fold and thrust belt south and west of Monterrey. The sedimentary cover of Cretaceous and Jurassic rocks in the Sabinas and Parras basins ranges from about 1,550 m (5,000 ft) to 9,000 m (30,000 ft) in thickness. Upper Jurassic rocks are composed of carbonate and dark organic shaly or sandy beds underlain by an unknown thickness of Late Jurassic and older redbed clastics and evaporites, including halite. Lower Cretaceous rocks are mainly platform carbonate and fine clastic beds with some evaporites (gypsum or anhydrite) deposited in two main rudist reef-bearing carbonate cycles. Upper Cretaceous rocks are mainly continental and marine clastic beds related to early development of the Laramide orogeny. This Upper Cretaceous sequence contains a marine shale and deltaic clastic complex as much as 6,000 m (20,000 ft) or more thick in the Parras basin, which grades northward and eastward to open marine, fine clastic beds. The Burgos basin, which is an extension of the Rio Grande embayment of the western Gulf of Mexico basin province, contains an eastward-thickening wedge of Tertiary continental and marine clastics. These beds are about 1,550 to 3,000 m (5,000-10,000 ft) thick in the outcrop belt on the west side of the basin and thicken to more than 16,000 m (50,000 ft) near the Gulf Coast.

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