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At least 1,009 records · Page 56Linked to original sources
USGS1969

Ground-water resources of the Wind River Indian Reservation, Wyoming

The area of this investigation is in the western part of the Wind River Basin and includes parts of the Absaroka, Washakie, Wind River, and Owl Creek Mountains. The purposes of the study were to determine the general hydrologic properties of the rocks in the area and the occurrence and quality c f the water in them. Structurally, the area is a downfolded basin surrounded by upfolded mountain ranges. Igneous and metamorphic rocks of Precambrian age are exposed in the mountains: folded sedimentary rocks representing all geologic periods, except the Silurian, crop out along the margins of the basin; and relatively flat-lying Tertiary rocks are at the surface in the central part of the basin. Surficial sand and gravel deposits of Quaternary age occur along streams and underlie numerous terraces throughout the basin. The potential yield and quality of water from most rocks in the area are poorly known, but estimates are possible, based on local well data and on data concerning similar rocks in nearby areas. Yields of more than 1,000 gpm are possible from the rocks comprising the Bighorn Dolomite (Ordovician), Darby Formation (Devonian), Madison Limestone (Mississippian), and Tensleep Sandstone (Pennsylvanian). Total dissolved solids in the water range from about 300 to 3,000 ppm. Yields of as much as several hundred gallons per minute are possible from the Nugget Sandstone (Jurassic? and Triassic?). Yields of 20 gpm or more are possible from the Crow Mountain Sandstone (Triassic) and Sundance Formation (Jurassic). Dissolved solids are generally high but are less than 1,000 ppm near outcrops in some locations. The Cloverly and Morrison (Cretaceous and Jurassic), Mesaverde (Cretaceous) and Lance(?) (Cretaceous) Formations may yield as much as several hundred gallons per minute, but most wells in Cretaceous rocks yield less than 20 gpm. Dissolved solids generally range from 1,000 to 5,000 ppm but may be higher. In some areas, water with less than 1,000 ppm dissolved solids may be available from the Cloverly and Morrison Formations. Tertiary rocks yield a few to several hundred gallons per minute and dissolved solids generally range from 1,000 to 5,000 ppm. Wells in the Wind River Formation (Eocene) yield about 1.-500 gpm of water having dissolved solids of about 200-5,000 ppm. Yields of a few to several hundred gallons per minute are available from alluvium (Quaternary). Dissolved solids range from about 200 to 5,000 ppm. Many parts of the Wind River Irrigation Project have become waterlogged. The relation of drainage problems to geology and the character and thickness of rocks in the irrigated areas are partly defined by sections drawn on the basis of test drilling. The drainage-problem areas are classified according to geologic similarities into five general groups: flood plains, terraces, underfit-stream valleys, slopes, and transitional areas. Drainage can be improved by open drains, buried drains, relief wells, and pumped wells or by pumping from sumps or drains. The methods that will be most successful depend on the local geologic and hydrologic conditions. In several areas, the most effective means of relieving the drainage problem would be to reduce the amount of infiltration of water by lining canals and ditches and by reducing irrigation water applications to the optimum. Water from underground storage in alluvium could supplement water from surface storage in some areas. A few thousand acre-feet of water per square mile are in storage in some of the alluvium. The use of both surface and underground storage would reduce the need for additional surface-storage facilities and also would alleviate drainage problems in the irrigated areas.

Water Supply Paper↗
USGS1964

Ground water in folded Cretaceous sandstone of the Bhachau area, Kutch, India, with reference to the Kandla Port water supply

This report is based on an investigation of the availability of ground-water supplies in the Bhachau area for the nearby Kandla Port and township development undertaken by the Government of India. This seaport lies on an estuary of the Gulf of Kutch in western India and in the eastern part of the State of Kutch. The fieldwork on the investigation was carried on from November 1952 through April 1953 with continuing hydrologic observations through 1954-55. The fieldwork included: geologic mapping and delimitation of the principal aquifers of the region; preparation of water-table maps; a detailed inventory of existing wells and springs; observations of significant water table fluctuations; preparation of isobicarb, isochlor and isosulf maps to show the areal distribution of ground-water salinity. The Bhachau area includes about 116 square miles in eastern Kutch and lies in a belt of semiarid low-latitude steppes. The mean annual rainfall is about 15 inches, most of which falls from late June to late September during the southwest monsoon. The area includes a central sandy upland ranging from about 100 to 250 feet above sea level ; a northern lowland of between about 50 to 125 feet altitude that slopes north to the Great Rann of Kutch; a belt of low buttes and discontinuous ridges ranging from about 200 to 275 feet above sea level; and southern lowland which slopes in a southerly to southeasterly direction from an altitude of about 125 feet to 25 feet or less near the Gulf of Kutch. The principal streams are Kageshwar Vokra and Kara Vokra which drain north to the Great Rann and Kotwala Vokra and Dalwala Vokra which drain south toward the Gulf of Kutch. The rocks of the Bhachau area include nonmarine and marine sediments of Mesozoic, Tertiary, and Quaternary age and volcanic rocks of late Mesozoic to early Tertiary age. The oldest rocks in the area are medium- to coarse-grained white to buff current-bedded friable sandstone with occasional partings of white silty shale of the Upper Bhuj series that has been assigned to the Early Cretaceous. The soft friable sandstone of the Upper Bhuj series constitutes the most productive ground-water reservoir in the Bhachau area. At present (1955) there are nine irrigated tracts for which water is obtained from dug wells less than 90 feet deep in the Upper Bhuj. These wells are worked by bullocks and 'motes' (leather bags) at withdrawal rates ranging from about 6,000 to 24,000imperial gallons per day; however, many existing individual wells if equipped with mechanical pumps are capable of yielding 100,000 gallons per day. The Deccan trap of Late Cretaceous to Eocene age occurs in a sequence of basaltic lava flows in the Bhachau area, but trap dikes, sills and plugs that are common in other parts of Kutch have not been observed in the area. Laterite of probable Eocene age is extensive at the top of the Deccan trap, and in places where the lava flows are thin the parent rock has been almost completely lateritized. The Deccan lava flows or the laterite, where the trap is absent, rest disconformably on the Upper Bhuj. No wells have been observed in the Deccan trap of the Bhachau area, but it is possible that locally small supplies of good water may be obtained from these rocks. The Tertiary sediments, which are assigned to the Manchhar series of Pliocene age, generally rest on the laterite or the Deccan trap ; but where both are absent, the Manchhar rests directly on the Upper Bhuj. The Manchhar series includes massive reddish-brown gypseous clay shales, laminated gray siltstones, some limestone, mottled sandstone, and laterite trap gravel. Only meager supplies of brackish water are obtained from wells in these sediments. Along the channels of Kotwala, Dalwala, Kageshwar, and Kara Vokras are narrow bands of unconsolidated coarse sand with fine gravel of Quaternary age. No wells were observed in these deposits, but it is possible that locally they may contain small supplies of bracki

Water Supply Paper↗
USGS1965

Water-supply potential from an asphalt-lined catchment near Holualoa Kona, Hawaii

The Jenkins-Whitesburg area includes approximately 250 square miles In Letcher and Pike Counties in the southeastern part of the Eastern Coal Field. In this area ground water is the principal source of water for nearly all rural families, most public supplies, several coal mines and coal processing plants, and one bottling plant. The major aquifers in the Jenkins-Whitesburg area are the Breathitt and Lee Formations of Pennsylvanian age. Other aquifers range in age from Devonian to Quaternary but are not important in this area because they occur at great depth or yield little or no water. The Breathitt Formation occurs throughout the area except along the crest and slopes of Pine Mountain and where it is covered by unconsolidated material of Quaternary age. The Breathitt Formation consists of shale, sandstone, and lesser amounts of coal and associated underclay. The yield of wells penetrating the Breathitt Formation ranges from less than 1 to 330 gallons per minute. Well yield is controlled by the type and depth of well, character of the aquifer, and topography of the well site. Generally, deep wells drilled in valleys of perennial streams offer the best potential for high yields. Although enough water for a minimum domestic supply (more than 100 gallons per day) may be obtained from shale, all high-yielding wells probably obtain water from vertical joints and from bedding planes which are best developed in sandstone. About 13 percent of the wells inventoried in the Breathitt Formation failed to supply enough water for a minimum domestic supply. Most of these are shallow dug wells or drilled wells on hillsides or hilltops. Abandoned coal mines are utilized as large infiltration galleries and furnish part of the water for several public supplies. The chemical quality of water from the Breathitt Formation varies considerably from place to place, but the water generally is acceptable for most domestic and industrial uses. Most water is a calcium magnesium bicarbonate or sodium bicarbonate type, and nearly all sampled water contained enough iron to stain cooking and laundry utensils. The water ranged from soft to very hard, and only one well in the Breathitt Formation produced salty water. The absence of salty water may be due to abundant fractures which are associated with the Pine Mountain fault and which have allowed fresh water to enter the formation. The Lee Formation underlies the Cumberland Mountain section and is exposed along the crest and southeast slope of Pine Mountain. The Lee Formation consists of massive sandstone and conglomerate with thin beds of shale and a few thin coal seams. Although the Lee Formation is tapped by only a few wells in this area, it is potentially an important aquifer. Wells penetrating the Lee Formation in the Cumberland Mountain section would probably yield water under artesian pressure. Unlike most water from the Lee Formation in other part.3 of eastern Kentucky, all water from the Lee Formation in the Jenkins-Whitesburg area is fresh. All water from the Lee Formation contained more than 0.3 parts per million of iron and ranged from soft to moderately hard.

Water Supply Paper↗
USGS1967

Geology and ground water of the Savannah River Plant and vicinity, South Carolina

The area described in this report covers approximately 2,600 square miles in west-central South Carolina and includes the site of the Savannah River Plant, a major production facility of the U.S. Atomic Energy Commission. The climate, surface drainage, and land forms of the study area are typical of the southern part of the Atlantic Coastal Plain. Precipitation is normally abundant and fairly evenly distributed throughout the year, and the mean annual temperature is moderately warm (64?F). The major streams that drain the area (the Savannah, Salkehatchie, and Edisto Rivers) have low gradients and flow in a southeasterly direction toward the Atlantic Ocean. Surface features of the area include narrow, flat-bottomed, steep-sided valleys and broad gently rolling interfluvial areas. Those parts of the Coastal Plain included within the report area can be subdivided into the Aiken Plateau, the Congaree Sandhills, and the Coastal Terraces. The area is underlain by a sequence of unconsolidated and partly consolidated sediments of Late Cretaceous, Tertiary, and Quaternary age. The unconsolidated sediments were deposited unconformably on a basement of igneous and metamorphic rocks of Precambrian and Paleozoic age and sedimentary rocks of Triassic age. The basement rocks are similar to the granite-diorite complex of the Charlotte Belt, the metamorphosed rocks of the Carolina Slate Belt, and the consolidated sediments of the Newark Group. The unconsolidated sediments strike about N. 60 ? E. and dip 6-20 feet per mile to the southeast. They form a wedge-shaped mass that increases in thickness toward the southeast to slightly more than 1,200 feet in the vicinity of Allendale, S.C., on the southeast or downdip side of the study area. The oldest or lowermost unconsolidated sedimentary unit, the Tuscaloosa Formation of Late Cretaceous age, is overlain in the subsurface by beds that are also probably Late Cretaceous in age and that herein are named the Ellenton Formation. The Upper Cretaceous deposits are, in turn, overlain by the, McBean Formation and the Congaree(?) Formation of middle Eocene age, the Barnwell Formation of late Eocene age, the Hawthorn Formation of early and middle Miocene age, and by fluvial and marine(?) terrace deposits of Pliocene(?), Pleistocene, and Recent age. In the mapped area, the Congaree(?) Formation includes undifferentiated rocks (mostly Congaree and Barnwell Formations and some Mcbean outliers). (See map explanation.) Structurally, the Upper Cretaceous sediments are overlapped to the northwest by Tertiary deposits. A preliminary geologic map of the general area is included in the report. The principal aquifer in the area is composed of the beds of medium to coarse sand and gravel contained in the Tuscaloosa and Ellenton Formations. Subordinate aquifers include deposits of sand and limestone of Tertiary and Quaternary age. The ground water in the principal aquifer occurs under water-table conditions in the outcrop area of the Tuscaloosa Formation in the northern and western parts of the study area, but it is under artesian pressure downdip in the southern and eastern parts of the study area. Contours drawn on the piezometric surface of the water in the principal aquifer indicate that water is recharged to the aquifer mainly by leakage through the overlying Tertiary formations. Likewise, the piezometric contours show that the outcrop area of the Tuscaloosa Formation functions chiefly as an area of discharge. Doubtless, water is also discharged from the aquifer by moving downdip to areas near the coast where the prevailing hydraulic gradient may favor the upward leakage of water through the upper confining beds. The hydraulic properties of the principal aquifer were determined by a series of pumping tests. The results indicate that the aquifer is highly productive and could supply 15 million gallons per day in the vicinity of the Savannah River Plant without exceeding the available drawdown.

South Carolina↗
USGS1984

Availability and quality of water from the Dakota aquifer, northwest Iowa

The Dakota aquifer in northwest Iowa consists of sandstones in the Dakota Formation. It underlies most of the study area and is the most extensive source of ground water in the area. Individual sandstone beds are from less than 10 to more than 150 feet thick. The cumulative thickness of sandstone is more than 200 feet throughout much of the area. The aquifer is confined by overlying Cretaceous limestone and shale, Quaternary glacial deposits and loess. The underlying confining material is shale of the Dakota Formation, undifferentiated Paleozoic age rocks, or Precambrian crystalline rock. Water flows through the aquifer from the northcentral part of the study area to the east, south and southwest. Recharge is dominantly by infiltration from the land surface through the confining materials. Discharge is to underlying Paleozoic aquifers and to the alluvium and glacial outwash deposits along the Missouri and Big Sioux Rivers in the southwest part of the area. Flow components toward bedrock valleys may reflect discharge to Quaternary sand and gravel deposits in these valleys. Pumping tests conducted in the study area indicate a narrow" range of hydraulic conductivities of the Dakota aquifer, from 37 to 50 feet per day. Consequently, an average hydraulic conductivity of 40 feet per day was used to estimate the potential yield to wells completed in the aquifer. Yields of more than 250 gallons per minute can be expected throughout much of the study area and more than 1,000 gallons per minute could be produced in some areas. The quality of water from the Dakota is a calcium, magnesium, sulfate type. It is generally suitable for irrigation purposes, based on comparisons of sodium adsorption ratios and electrical conductivities. In some areas the aquifer has water with high salinity hazard that may restrict its use to irrigation of only well-drained types of soil. The concentration of radium-226 and other radionuclides exceeds recommended limits at several sites. The quality of water pumped from the aquifer may be altered by induced leakage from the underlying aquifers in Paleozoic age rocks if withdrawals reverse the pattern of natural flow from the Dakota into the Paleozoic aquifers. Evidence for such a reversal exists in the area around the city of LeMars.

Iowa↗
USGS2014

Interpreting the paleozoogeography and sea level history of thermally anomalous marine terrace faunas: A case study from the the last interglacial complex of San Clemente Island, California

Marine invertebrate faunas with mixtures of extralimital southern and extralimital northern faunal elements, called thermally anomalous faunas, have been recognized for more than a century in the Quaternary marine terrace record of the Pacific Coast of North America. Although many mechanisms have been proposed to explain this phenomenon, no single explanation seems to be applicable to all localities where thermally anomalous faunas have been observed. Here, we describe one such thermally anomalous fossil fauna that was studied on the second emergent marine terrace at Eel Point on San Clemente Island. The Eel Point terrace complex is a composite feature, consisting of a narrow upper bench (terrace 2a) and a broader lower bench (terrace 2b). Terrace 2b, previously dated from ∼128 ka to ∼114 ka, was thought to date solely to marine isotope stage (MIS) 5.5, representing the peak of the last interglacial period. Nevertheless, the fauna contains an extralimital northern species and several northward-ranging species, as well as an extralimital southern species and several southward-ranging species. Similar faunas with thermally anomalous elements have also been reported from San Nicolas Island, Point Loma (San Diego County), and Cayucos (San Luis Obispo County), California. U-series dating of corals at those localities shows that the thermally anomalous faunas may be the result of mixing of fossils from both the ∼100-ka (cool-water) and the ∼120-ka (warm-water) sea level high stands. Submergence, erosion, and fossil mixing of the ∼120-ka terraces by the ∼100-ka high-sea stand may have been possible due to glacial isostatic adjustment (GIA) effects on North America, which could have resulted in a higher-than-present local sea level stand at ∼100 ka. The terrace elevation spacing on San Clemente Island is very similar to that on San Nicolas Island, and we hypothesize that a similar mixing took place on San Clemente Island. Existing fossil records from older terraces elsewhere in California also show thermally anomalous elements, indicating that the scenario presented here for the last interglacial complex may have applicability to much of the marine Quaternary record for the Pacific Coast.

California↗
USGS1999

The Puelche volcanic field: Extensive Pleistocene rhyolite lava flows in the Andes of central Chile

A remote volcanic field in the rugged headwaters of the Río Puelche and Río Invernada (35.8°S) constitutes the largest cluster of Quaternary rhyolite lava flows yet identified in the Andean Southern Volcanic Zone. The Puelche Volcanic Field belongs to an intra-arc belt of silicic magmatic centers that extends, at least, 140 km north-south and lies well east of the volcanic front but nonetheless considerably west of the intraplate extensional fields of basaltic and alkaline centers of pampean Argentina. The authors' mapping has distinguished one shallow intrusive mass of early Pleistocene biotite rhyodacite (70.5% SiO 2 ), 11 eruptive units of mid-Pleistocene high-K biotite-rhyolite lava (71.3-75.6% SiO 2 ), and 4 eruptive units of basaltic andesite (53.95-4.9% SiO 2 ), the conduits of which cut some of the rhyolites. Basal contacts of the rhyolite lava flows (and subjacent pyroclastic precursors) are generally scree covered, but glacial erosion has exposed internal flow structures and lithologic zonation superbly. Thicknesses of individual rhyolite lava flows range from 75 m to 400 m. Feeders for several units are well exposed. Cliff-draping unconformities and intracanyon relationships among the 11 rhyolite units show that the eruptive sequence spanned at least one glacial episode that accentuated the local relief. Lack of ice-contact features suggests, however, that all or most eruptions took place during non-glacial intervals probably between 400 ka and 100 ka. Post-eruptive glacial erosion reduced the rhyolites to several non-contiguous remnants that altogether cover 83 km 2 and represent a surviving volume of about 21 km 3 . Consideration of slopes, lava thicknesses, and paleotopography suggest that the original area and volume were each about three times greater. Phenocryst content of the rhyolites ranges from 1 to 12%, with plagioclase>>biotite>FeTi oxides in all units and amphibole conspicuous in the least silicic. The chemically varied basaltic andesites range from phenocryst-poor to phenocryst-rich, exhibiting large differences in proportions of clinopyroxene, olivine, plagioclase, and xenocrystic quartz. Compositional bimodality of the volcanic field is striking, there being no Quaternary eruptive units having SiO 2 contents between 55 and 70%. Major and trace element compositions of the mafic and silicic rocks are nonetheless typical of continental-margin arc suites, not of intracontinental suites. The lack of intermediate eruptive units and the differences between the mafic and rhyolitic lavas in Sr-isotope composition suggest that the rhyolites fractionated from a hybrid parent rather than continuously from basaltic magma. The rhyolites may contain larger contributions of upper-crustal partial melts than do silicic products of the volcanic-front centers 30 km to the west.

Revista Geologica de Chile↗
USGS1983

GEOLOGIC FRAMEWORK FOR GEOTHERMAL ENERGY IN THE CASCADE RANGE.

Quaternary volcanoes of the Cascade Range form a 1200-km-long belt from northern California to southwest British Columbia and lie above the subduction zone formed as the Juan de Fuca plate is consumed beneath North America. Volcanoes throughout this belt may have been active during Quaternary time, and many have erupted within Holocene time. Thermal springs are few and inconspicuous. Surface expression of hydrothermal systems possibly is masked by infiltration of abundant rainwater and snowmelt. Several geologic and geophysical features suggest that the Oregon and California parts of the Cascades are characterized by moderate east-west crustal extension, tectonic regime conducive to relatively widespread volcanism and to the formation of normal fault zones of potentially high permeability. Refs.

Conference Paper↗
USGS2003

The stream net as an indicator of cryptic systematic fracturing in Louisiana

The stream net in many parts of Louisiana includes straight reaches with preferred alignment in a few directions, with some examples spanning tens of kilometers. In places the reaches form classic rectangular drainage patterns. These characteristics are obvious on maps at a variety of scales, and are recognizable on some portion of nearly every 7.5-minute quadrangle in the state, excepting those quadrangles situated entirely within the Ho??ocene coastal marshes or the Holocene flood plains of the larger rivers. Such patterns of lineaments are reminiscent of patterns associated with systematic fracturing in other regions. In Louisiana, however, verification and measurement of fractures that may exist in the vicinity of rectilinear drainage anomalies is problematic because surface deposits are comparatively young and sparsely exposed, and tend, especially near waterways, to be heavily weathered and vegetated. An indirect approach to evaluating the potential influence on drainage by fracturing involves evaluating the frequency distribution of stream-course orientations based on its degree of similarity with that of the strikes of previously mapped or reported fractures (faults and/or joints). A rose diagram of orientation frequencies for the stream net of the entire state, created utilizing a publicly available line dataset processed into 100-m segments (N 290,000), shows a nonrandom distribution with three visually identifiable trends: the strongest, oriented essentially N-S; a subsidiary trend oriented N20??-30??W; and a weak trend oriented N80??-90??W. The entire population of orientations yields a mean direction of N17.5??W ?? 4.2?? with a probability of 95 percent. The strike frequencies of mapped faults show little correspondence with these trends. This suggests, if mapped faults are at least representative of actual faults, that insofar as apparent lineaments reflect structure and not the influence of a south-southeasterly regional drainage gradient, they predominantly reveal the influence of joints. These could reflect either a Quaternary stress regime, or propagation in young sediment of a structural pattern in underlying older strata. The data available at present do not compel either interpretation, though in south Louisiana at least, where reactivated early Tertiary growth faults have surface expression that in places is juxtaposed with differently oriented drainage lineaments, propagation of a preexisting pattern from depth appears plausible. Widespread systematic fracturing in this predominantly Quaternary coastal-plain setting could have important implications for groundwater flow and for other processes that depend substantially on permeability.

Southeastern Geology↗
USGS2011

The regional structural setting of the 2008 Wells earthquake and Town Creek Flat Basin: implications for the Wells earthquake fault and adjacent structures

The 2008 Wells earthquake occurred on a northeast-striking, southeast-dipping fault that is clearly delineated by the aftershock swarm to a depth of 10-12 km below sea level. However, Cenozoic rocks and structures around Wells primarily record east-west extension along north- to north-northeast-striking, west-dipping normal faults that formed during the middle Miocene. These faults are responsible for the strong eastward tilt of most basins and ranges in the area, including the Town Creek Flat basin (the location of the earthquake) and the adjacent Snake Mountains and western Windermere Hills. These older west-dipping faults are locally overprinted by a younger generation of east-dipping, high-angle normal faults that formed as early as the late Miocene and have remained active into the Quaternary. The most prominent of these east-dipping faults is the set of en-échelon, north-striking faults that bounds the east sides of the Ruby Mountains, East Humboldt Range, and Clover Hill (about 5 km southwest of Wells). The northeastern-most of these faults, the Clover Hill fault, projects northward along strike toward the Snake Mountains and the approximately located surface projection of the Wells earthquake fault as defined by aftershock locations. The Clover Hill fault also projects toward a previously unrecognized, east-facing Quaternary fault scarp and line of springs that appear to mark a significant east-dipping normal fault along the western edge of Town Creek Flat. Both western and eastern projections may be northern continuations of the Clover Hill fault. The Wells earthquake occurred along this east-dipping fault system. Two possible alternatives to rupture of a northern continuation of the Clover Hill fault are that the earthquake fault (1) is antithetic to an active west-dipping fault or (2) reactivated a Mesozoic thrust fault that dips east as a result of tilting by the west-dipping faults along the west side of the Snake Mountains. Both alternatives are precluded by the depths of the earthquake and aftershocks, about 8 km and as deep as 12 km, respectively. These depths are below where an antithetic fault would intersect any main fault, and a tilted, formerly shallow and sub-horizontal thrust fault would not extend to depths of more than about 5–6 km. The east-dipping, high-angle, earthquake fault cuts older west-dipping faults rather than reactivating them, highlighting a change in the structural style of Basin and Range extension in this region from closely-spaced, west-dipping faults that rotated significantly during slip and accommodated large-magnitude extension, to widely-spaced, high-angle faults that accommodate much less total strain over a long time span.

Nevada↗
USGS1973

Geology and water resources of the Wharton Tract and the Mullica River basin in southern New Jersey

The Wharton Tract is an area of 150 square miles located in the Mullica River basin in southern New Jersey's Pine Barrens region. The tract is a relatively flat, low-lying, generally sandy area containing shallowly incised streams. The larger streams are commonly bordered by swamps. The tract was purchased by the State primarily as a water-supply preserve, but also for conservation and recreational purposes. Mean streamflow at three continuous record gaging stations in the Wharton Tract is: Mullica River near Batsto (46.1-square mile drainage area), 6 mgd (million gallons per day); Batsto River at Batsto (70.5-square mile drainage area), 81 mgd; Oswego River at Harrisville (64.0-square mile drainage area), 55 mgd. Thus mean discharge from this 180.6-sq mi (square mile) area is 202 mgd or 1.12 mgd per sq mi. Principal aquifers in the Wharton Tract and Mullic River basin are in the Kirkwood Formation of middle Miocene age, Cohansey Sand of Miocene(?) and Pliocene(?) age, and in overlying hydraulically connected deposits of Quaternary age. The Kirkwood Formation is composed of sand, silt, and clay. Diverse lithologies represent deposition in different environments such as nearshore marine, barrier bar, lagoonal, estuarine, and tidal marsh. Hydraulic characteristics of the Kirkwood in the Mullica River basin are virtually unknown. Most Kirkwood aquifers in the basin are believed to be hydraulically connected with the overlying Cohansey Sand. The Cohansey Sand is dominantly a quartz sand containing minor amounts of pebbly sand, silty sand, and interbedded clay. Almost all of the Wharton Tract and most of the Mullica River basin lie within the sandier area of the Cohansey, which contains approximately 75 percent sand beds and 25 percent silt and clay beds. Data from test drilling show that the upper 100 feet of sediments in the Wharton Tract contain about 93 percent sand beds, 3.5 percent clay beds, and 3.5 percent silt beds. The Cohansey in the Tract ranges in thickness from less than 50 feet to about 180 feet; the average thickness is about 125 feet. The Cohansey Sand is believed to be, in overall aspect, a deltaic deposit. It contains materials that were deposited locally in nearshore-marine, fluvial, estuarine, lagoonal, and beach environments. The hydraulic conductivity of Cohansey aquifer material ranges from about 90 to 250 feet per day (660 to 1,885 gallons per day per square foot) in southern New Jersey. One aquifer test in the Wharton Tract gives an average value of 130 feet per day (1,000 gallons per day per square foot). The transmissivity of the Cohansey Sand aquifer through most of the Wharton Tract is typically between 10,000 and 20,000 square feet per day (75,000 and 150,000 gallons per day per foot). Deposits of Quaternary age form a discontinuous veneer lying unconformably above the Cohansey Sand. The most important hydrologic function of most of these deposits is to absorb precipitation and transmit the water to the underlying Cohansey Sand. Thicker deposits of estuarine sand and clay of the Cape May Formation fill a channel in the underlying Cohansey Sand along the lower reaches of the Mullica River. This channel deposit is 85 feet thick near Batsto. Ground water and surface water in the Mullica River basin are low in dissolved solids, generally less than 50 mg/1 (milligrams per liter). Iron concentrations are generally high, up to 49,000 micrograms per liter (49 mg/1) in ground water and up to 7,100 micrograms per liter (7.1 mg/1) in the streams. The water is acidic as indicated by typical pH values of from 4.5 to 6.5. Color of the surface water is commonly high, ranging from 3 - 150 platinum-cobalt units. After appropriate treatment these waters are acceptable for most uses. The Wharton Tract is well situated to support the growing water needs of nearby New Jersey communities. Maximum development of water can be achieved by conjunctive use of ground and surface water. During most of the year, some water would be withdrawn either directly from streams or from adjacent wells. During periods of low flow during summer or fall water would be pumped from wells farther from the stream~. From analysis of flow-duration curves it is estimated that 70 mgd of water could be developed with minimal effect upon low flows in the half of the tract above the gaging stations on the Mullica and Batsto Rivers. The quantity available in the entire tract is greater, possibly in the order of 150 mgd. With augmentation of streamflow by pumping from ground water, it is likely that considerably more water could be safely used on a perennial basis. A possibility exists for multiple use of the water resources of the Mullica River through construction of an inexpensive tide barrier at the Garden State Parkway. This would create a fresh water lake in a State forest, park, and recreational area, which would also provide a flexible and economical water supply for much of the Atlantic coastal resort development.

New Jersey↗
USGS1946

Geology of the Hawaiian islands

A brief summary of the geography, climate, and geomorphology is given. Streams develop slowly after the extinction of a volcano because of the high permeability of the rock. Once established they cut rapidly because of the steep slopes and fractured condition of the rock. Stream erosion varies enormously on different slopes of the same mountain due to the great differences in rainfall and to other causes. Six reasons are given for the development of amphitheater-headed valleys. Marine erosion has formed cliffs as much as 1,000 feet high on the leeward side and 3,000 feet high on the windward side of some of the domes. The islands have undergone a complex series of emergences and submergences leaving marine fossiliferous limestone up to 1,070 feet above sea level and valleys drowned more than 1,200 feet. Twelve terrace levels are recognized. Some are definitely eustatic. A synopsis is given of the present knowledge of the geology of each volcanic mountain, as well as a table of the rock units, and geologic maps of all major islands. The volcanoes pass through four major phases between birth and extinction and are built around one minor and two major rift zones. The volcanoes began their history above sea level in the Tertiary. Most of them became dormant either before or during the early Quaternary. Activity was renewed in the late Quaternary. Mauna Kea was glaciated in the late Pleistocene. The character of each islet in the archipelago is tabulated.

Hawaii↗
USGS1970

Geology and ground-water resources of Cerro Gordo County, Iowa

The basic geologic framework underlying Cerro Gordo County consists of an igneous or metamorphic Precambrian basement complex overlain by, in ascending order, consolidated sedimentary rocks of Precambrian, Cambrian, Ordovician, Devonian, Mississippian, and Cretaceous age, and unconsolidated sand, gravel, and clay of Quaternary age. Structurally the county is in the northern part of the Iowan Basin, and the sedimentary units of Cambrian through Devonian age dip southward at 9 to 14 feet per mile. Three major glacial advances, the Nebraskan, Kansan, and Wisconsin, covered all or part of the county during the Pleistocene Epoch and left behind glacial drift consisting of 0 to 125 feet of till and related outwash deposits. De posits of Holocene age, aside from surficial soil, are thin and scattered. Ground water occurs in the sedimentary units of Cambrian through Mississippian age and in the glacial drift and outwash deposits of Quaternary age. The chief aquifers, in ascending order, are the deep Cambrian sandstones, Jordan aquifer, St. Peter Sandstone, Devonian and Mississippian limestones and dolomites, and the Pleistocene glacial drift and related interglacial deposits. Units between the St. Peter Sandstone and the Devonian limestones, the Platteville, Decorah, Galena, and Maquoketa Formations, are of low permeability and are considered to be an aquiclude in comparison to the overlying and under lying units. The deep Cambrian sandstones will yield about 60 gpm (gallons per minute) to an individual well; the Jordan aquifer about 1,200 gpm; the St. Peter Sandstone 30 to 200 gpm; the Devonian limestones and dolomites 120 to 200 gpm; and the glacial outwash or shallow bedrock generally will yield 10 gpm or more. The Jordan aquifer supplies large quantities of water for municipal and industrial use at Mason City. Pumping tests on wells tapping the Jordan in that area show that the aquifer has a transmissibility of about 35,000 gallons per day per foot and a storage coefficient of 2 x 10 -4 Pumping in the Mason City area from 1912 to 1969 has produced about 200 feet of draw down in the areas of maximum withdrawal. Ground water in Cerro Gordo County is of suitable chemical quality for domestic, industrial, or municipal use. The total dis solved solids ranges from 152 mg/l (milligrams per liter) in water from the shallow bedrock to 885 mg/l in water from the deep Cambrian sandstones. Water from the Jordan, which is the most productive aquifer in the county, generally contains less than 500 mg/l dissolved solids. Ground water is the major source of water supplies throughout Cerro Gordo County. The majority of wells in the county are used for domestic and stock supplies, but the largest withdrawals of water are for municipal and industrial supplies. Municipal pumpage in the county in 1968 was about 1.5 billion gallons; industrial pumpage was about 1.8 billion gallons and most of the water was obtained from the Jordan aquifer. If future development of water from the Jordan aquifer is to be to the best economical advantage, careful consideration should be given to the location, capacity, and pumping schedules of proposed wells and nearby existing wells so that local overdevelopment or excessive interference do not occur.

Iowa↗
USGS1946

Ground water in Tooele Valley, Tooele County, Utah

Tooele Valley is a typical basin of the Basin and Range Province located about 30 miles southwest of Salt Lake City. It is roughly 15 miles long and 10 miles wide and has a population of about 7,000. Bordered on the west by the Stansbury Range, on the east by the Oquirrh Range, and on the south by South Mountain, it opens northward to Great Salt Lake. The bordering mountain ranges are formed by Paleozoic rocks ranging in age from Lower Cambrian to Pennsylvanian but with the Ordovician and Silurian periods unrepresented. There is no sedimentary record of the interval between Pennsylvanian and Tertiary times, and the Tertiary, Quaternary, and Recent sediments are of continental origin. These continental deposits play the dominant role in the ground-water hydrology of the basin, and were mapped and studied in detail. Pleistocene sediments are of major importance because they form the surface rock over most of the area, and give rise to conditions which yield water by artesian flow in the lower part of the valley. The development of the present land forms in this area began with the folding of Paleozoic and probably Mesozoic sediments during the Laramide revolution. The cycle of highland erosion and lowland deposition thus initiated has continued through recurrent uplift along Basin-Range faults to the present day. The principal physiographic subdivisions of the valley were developed as a result of the Basin-Range faulting, which began early in the Tertiary and has continued to Recent times. There are about 1,100 wells in Tooele Valley, about 90 per cent of which yield or have yielded water by artesian flow. Most of them are located in the lower part of the valley below an altitude of 4,400 feet. These wells and many of the springs derive their water from the unconsolidated Quaternary sediments, which include discontinuous, lenticular and commonly elongated bodies of sand, clay, gravel, and boulders of alluvial origin alternating and inter-fingered with lacustrine beds of the same materials which are more regularly stratified and better assorted. The larger springs are intimately related to the bedding planes and faults in the bedrock and alluvial formations. The well assorted sands and gravels deposited along the shore lines of Lake Bonneville are important as recharge areas for the artesian reservoir.

Utah↗
USGS1970

Major thermal springs of Utah

As part of a study of the springs of Utah, reconnaissance data were obtained on the thermal, chemical, and geologic characteristics of the major thermal springs or Utah. Only three of the springs have temperatures near the boiling point of water; the maximum recorded temperatures of these springs range from 185° to 189° F. All three springs are in or near areas of late Tertiary or Quaternary volcanism. Temperatures of the thermal springs studied ranged from 68° to 189° F. Nearly all thermal springs in Utah are in or near fault zones. Very few of these springs issue from volcanic rocks, but several springs are close to areas of late Tertiary or Quaternary volcanic rocks.

Utah↗
USGS2019

Right-lateral fault motion along the slope-basin transition, Gulf of Santa Catalina, southern California

An active fault system carrying a significant component of right-lateral strike-slip motion extends for ~60 km along the slope–basin transition, ~10 to 20 km offshore of the southern California coast from La Jolla to Dana Point. From south to north, this fault system includes the Carlsbad, San Onofre, and San Mateo fault zones. High-resolution single channel minisparker and chirp seismic reflection data gathered from 2006 to 2011 reveal complex and variable fault zones that are generally characterized by nearly vertical to steeply east-dipping faults with a reverse slip component. The Carlsbad fault zone shows evidence of reverse motion followed by normal separation and probably also includes a component of strike-slip offset. The San Onofre fault zone shows clear evidence of right-lateral slip, offsetting submarine gullies near the base of the slope by approximately 60 m. North of these offset gullies, the base of the slope bends about 30° to the west, following the trend of the San Mateo fault zone, but strands of the San Onofre fault zone trend obliquely up slope, appearing to merge with the Newport–Inglewood fault zone at the shelf edge. These San Onofre fault strands consist of several en echelon left-stepping segments separated by “pop-up” structures, which imply a significant component of right-lateral offset that may serve to transfer right-lateral slip from faults along the base of the slope to the Newport–Inglewood fault zone. Using approximate base Quaternary and base Holocene reflections, segments of the Carlsbad and San Onofre fault zones appear to have experienced right-lateral motion in the Holocene, whereas deformation along the San Mateo fault zone appears to represent a period of mostly pre-Quaternary transpression.

California↗
USGS1974

Metallogenic provinces of southeastern Pacific region

Metalliferous mineral deposits of the southeastern Pacific region include: (1) hydrothermal, magmatic, and sedimentary deposits of the Andean region, one of the great mineral belts of the world; (2) scattered hydrothermal deposits in the Antarctic Peninsula; and (3) metal-enriched pelagic sediments and ferromanganese nodules on the seafloor. Andean metalliferous deposits, the chief topic of this report, are for the most part spatially and genetically related to calc-alkaline plutons, subvolcanic intrusions, and volcanic rocks emplaced during the Andean orogeny of Late Triassic to Quaternary age. They are components of a single metallogenic province superimposed on two or more pre-Andean metallogenic provinces of Paleozoic and Precambrian(?) age. Deposits in the Antarctic Peninsula are similar in age and origin to the deposits in the Andes and are considered to belong to the Andean province. The Andean metallogenic province may be divided into several subprovinces, each parallel with the Andes and the continental margin and each having a dominant metal or suite of metals. The central Andes of Peru, northern Chile, and Bolivia, which contain the greatest concentration of exploitable deposits and the greatest variety of ore types, have as many as five linear, partly overlapping subprovinces. These subprovinces, from west to east (Pacific coast to the eastern Andean front), are characterized, respectively, by deposits of iron, copper, polymetallic base metals, tin, and gold. Calc-alkaline plutonic and volcanic rocks of the Andes, which probably originated by partial melting in the Benioff zone, show a general, though nonuniform progression of decreasing age from west to east. Igneous rocks of Jurassic and Cretaceous age are most abundant near the coast, whereas those of Tertiary and Quaternary age dominate in the Andes. Locally, intrusive rocks and associated ore deposits of widely different ages are juxtaposed. Several sources of the metals are probable; they include oceanic crust and pelagic sediments in the Benioff zone, some of which may have been enriched previously in certain metals at the ancestral East Pacific Rise, and metal-rich zones in the overlying mantle and continental crust.

AAPG Memoir↗
USGS2019

The benthic foraminifera cassidulina from the Arctic Ocean: Application to paleoceanography and biostratigraphy

We investigated the morphology, biostratigraphy, shell stable isotope composition and paleogeography of the common Arctic benthic foraminifera, Cassidulina teretis (Tappan 1951) (sometimes assigned to Islandiella (Nørvang 1958), for application to Quaternary paleoceanography. Cassidulina teretis, which has been studied by several generations of Arctic foraminiferal specialists, is used in Arctic Ocean paleoceanographic reconstructions based on foraminiferal assemblages and, increasingly, isotope shell chemistry. Here we review its modern and fossil distribution including discussions of its taxonomy, ecology, biostratigraphy and shell chemistry. Cassidulina teretis Tappan 1951, originally described from the Gubik Formation, northern Alaska coastal plain, has variability in test size, apertural morphology and development of an umbilical boss representing intra- and inter-population differences across the Arctic and subarctic in modern, Quaternary and Pliocene assemblages. Nonetheless, our studies and those previously published lead us to conclude that populations from the Arctic Ocean represent a single species proposed by Tappan as Cassidulina teretis. Its modern distribution is mainly 200 to 1000 m water depth, often living within the core of the relatively warm Atlantic Layer. However, shallower occurrences suggest other factors, such as food supply, are also critical to its ecology. The Holocene distribution of Cassidulina teretis in the Beaufort Sea boundary indicate millennial-scale changes in relative abundance related to changing Atlantic Layer influence, sea-ice cover, surface productivity and food availability. There are extremely large changes in its abundance during the last deglacial interval on the Yermak Plateau, Barents Sea slope and the Laptev Sea reflecting rapid ocean changes during the Bølling-Allerød, Younger Dryas, and Preboreal. Similarly, C. teretis abundance changes during the last 300,000 years allow us to use it, at least regionally, as a useful biostratigraphic marker. The stable isotopic composition of Cassidulina teretis tests holds promise for establishing an isotope stratigraphy across the Arctic Ocean and perhaps also in the Nordic Seas, off Iceland and in the northern North Atlantic Ocean, once disequilibrium values and offsets from other Arctic benthic species are more firmly established.

Micropaleontology↗