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Frank W. Trainer

Publications and source records attributed to Frank W. Trainer.

11 recordsLinked to original sources
USGS2000

Geothermal hydrology of Valles Caldera and the southwestern Jemez Mountains, New Mexico

The Jemez Mountains in north-central New Mexico are volcanic in origin and have a large central caldera known as Valles Caldera. The mountains contain the Valles geothermal system, which was investigated during 1970-82 as a source of geothermal energy. This report describes the geothermal hydrology of the Jemez Mountains and presents results of an earlier 1972-75 U.S. Geological Survey study of the area in light of more recent information. Several distinct types of thermal and nonthermal ground water are recognized in the Jemez Mountains. Two types of near-surface thermal water are in the caldera: thermal meteoric water and acid sulfate water. The principal reservoir of geothermal fluids is at depth under the central and western parts of the caldera. Nonthermal ground water in Valles Caldera occurs in diverse perched aquifers and deeper valley-fill aquifers. The geothermal reservoir is recharged by meteorically derived water that moves downward from the aquifers in the caldera fill to depths of 6,500 feet or more and at temperatures reaching about 330 degrees Celsius. The heated geothermal water rises convectively to depths of 2,000 feet or less and mixes with other ground water as it flows away from the geothermal reservoir. A vapor zone containing steam, carbon dioxide, and other gases exists above parts of the liquid-dominated geothermal zone. Two subsystems are generally recognized within the larger geothermal system: the Redondo Creek subsystem and the Sulphur Creek subsystem. The permeability in the Redondo Creek subsystem is controlled by stratigraphy and fault-related structures. Most of the permeability is in the high-angle, normal faults and associated fractures that form the Redondo Creek Graben. Faults and related fractures control the flow of thermal fluids in the subsystem, which is bounded by high-angle faults. The Redondo Creek subsystem has been more extensively studied than other parts of the system. The Sulphur Springs subsystem is not as well defined. The upper vapor-dominated zone in the Sulphur Creek subsystem is separated from the liquid-dominated zone by about 800 feet of sealed caldera-fill rock. Acid springs occur at the top of the vapor zone in the Sulphur Springs area. Some more highly permeable zones within the geothermal reservoir are interconnected, but the lack of interference effects among some wells during production tests suggests effective hydraulic separation along some subsystem boundaries. Chemical and thermal evidence suggests that the Sulphur Springs subsystem may be isolated from the Redondo Creek subsystem and each may have its own zone of upflow and lateral outflow. The area of the entire geothermal reservoir is estimated to be about 12 to 15 square miles; its western limit generally is thought to be at the ring-fracture zone of the caldera. The top of the reservoir is generally considered to be the bottom of a small- permeability 'caprock' that is about 2,000 to 3,000 feet below land surface. Estimated thicknesses to the bottom of the reservoir range from 2,000 to 6,000 feet. Reservoir temperatures measured in exploration wells range from 225 degrees Celsius just below the caprock to about 330 degrees Celsius in deeper drill holes. Pressures measured in exploration wells in the Redondo Creek area ranged from 450 to 1,850 pounds per square inch. Steam-producing zones have been encountered above the liquid- dominated zones in wells, but the extent of steam zones is not well defined. The reservoir contains a near-neutral, chloride-type water containing about 7,000 milligrams per liter dissolved solids. No thermal springs in the caldera have geochemical characteristics similar to those of the geothermal reservoir fluids sampled in wells. Oxygen-18 and deuterium isotope concentrations of geothermal reservoir fluid indicate a meteoric origin. The moat valleys in

Water-Resources Investigations Report↗
USGS1978

Geohydrologic data from the Jemez Mountains and vicinity, north-central New Mexico

The Jemez Mountains volcanic region, on the west margin of the Rio Grande rift in north-central New Mexico, is the site of studies for power development from geothermal heat. This report summarizes geohydrologic data to provide background information relative to the geothermal exploration and to investigate the usefulness of hydrology in assessment of the geothermal resource. Eleven tables present chemical, temperature, discharge , and other data for springs, wells, and streams. Accompanying figures show locations of the data points and present temperature profiles and geophysical logs for selected wells. (Woodard-USGS)

Water-Resources Investigations Report↗
USGS1975

Susanville-Honey Lake geothermal reconnaissance, southern Lassen County, California

As part of an appraisal of the nature and economic potential of the geothermal resource in the vicinity of Susanville and Honey Lake, the U.S. Bureau of Reclamation has been collecting geologic and hydrologic data, making resistivity surveys, obtaining thermal-infrared imagery, consulting with the U.S. Geological Survey, and drilling shallow temperature-gradientholes. This report, prepared by the Geological Survey in cooperation with the Bureau of Reclamation, presents the results of a brief reconnaissance study of the geothermal resource in the Susanville-Honey Lake area using theavailable geologic and hydrologic data.

California↗
USGS1975

Geohydrologic reconnaissance of the upper Potomac River basin

The upper Potomac River basin, in the central Appalachian region in Pennsylvania, Maryland, Virginia, and West Virginia, is a humid temperate region of diverse fractured rocks. Three geohydrologic terranes, which underlie large parts of the basin, are described in terms of their aquifer characteristics and of the magnitude and duration of their base runoff: (1) fractured rock having a thin regolith, (2) fractured rock having a thick regolith, and (3) carbonate rock. Crystalline rock in the mountainous part of the Blue Ridge province and shale with tight sandstone in the folded Appalachians are covered with thin regolith. Water is stored in and moves through fairly unmodified fractures. Average transmissivity (T) is estimated to be 150 feet squared per day, and average storage coefficient (S), 0.005. Base runoff declines rapidly from its high levels during spring and is poorly sustained during the summer season of high evapotranspiration. The rocks in this geohydrologic terrane are the least effective in the basin for the development of water supplies and as a source of dry-weather streamflow. Crystalline and sedimentary rocks in the Piedmont province and in the lowland part of the Blue Ridge province are covered with thick regolith. Water is stored in and moves through both the regolith and the underlying fractured rock. Estimated average values for aquifer characteristics are T, 200 feet squared per day, and S, 0.01. Base runoff is better sustained in this terrane than in the thin-regolith terrane and on the average .is about twice as great. Carbonate rock, in which fractures have been widened selectively by solution, especially near streams, has estimated average aquifer characteristics of T, 500 feet squared per day, and S, 0.03-0.04. This rock is the most effective in the basin in terms of water supply and base runoff. Where its fractures have not been widened by solution, the carbonate rock is a fractured-rock aquifer much like the noncarbonate rock. At low values the frequency of specific capacities of wells is much the same in all rocks in the basin, but high values of specific capacity are as much as 10 times more frequent in carbonate rock than in noncarbonate rock. Nearly all the large springs and high-capacity wells in the basin are in carbonate rock. Base runoff from the carbonate rock is better sustained during dry weather and on the average is about three times as great as base runoff from fractured rock having a thin regolith. The potential role of these water-bearing terranes in water management probably lies in the local development of large water supplies from the carbonate rock and in the possible manipulation of underground storage for such purposes as providing space for artificial recharge of ground water and providing ground water to be used for the augmentation of low streamflow. The chief water-quality problems in the basin--acidic mine-drainage water in the western part of the basin, local highly mineralized ground water, and the high nitrate content of ground water in some of the densely populated parts of the basin--would probably have little adverse affect on the use of ground water for low-flow augmentation.

Water Supply Paper↗
USGS1973

Formation of joints in bedrock by moving glacial ice

The orientation of joints in igneous and sedimentary rocks was measured at 21 localities in California, Maine, and New York to investigate the hypothesis that glaciation may open joints in bedrock. A summary of strikes of all joint sets shows the following pattern relative to the direction of glacial advance: two sets, thought to be extension joints, flank the direction of advance and are separated from it by about 10°; two sets, thought to be shear joints, flank the direction of advance by about 40°; and two sets, thought to be release joints, are about 70° to 80° from the direction of advance, or nearly perpendicular to the extension joints. An average of five joint sets, including three or four in this pattern, was found at each locality. The joints are believed to have been opened, in response to stress applied by the moving ice, along preexisting zones of weakness (potential regional joints) in the rock. Some new joints may have formed where no such zone was present near the position required for fracture under the applied stress. Additional investigation of the hypothesis is desirable because of its possible bearing on glacial erosion by quarrying, on interpretation of joint patterns in glaciated regions, and on the nature of aquifers in glaciated bedrock.

California, Maine, New York↗
USGS1964

Geology and ground-water resources of the Anchorage area, Alaska

The Anchorage area, at the head of Cook Inlet in south-central Alaska, occupies 150 square miles of a glaciated lowland and lies between two estuaries and the Chugach Mountains. Two military bases are in the area; Anchorage is the largest city in Alaska and the chief transportation center for this part of the State. The bedrock in the Anchorage area is chiefly Tertiary shale in the lowland and metamorphic rocks of Mesozoic age beneath the adjacent mountain slopes. Glacial drift which underlies nearly the entire area has an average thickness of several hundred feet and appears to include at least five sheets of deposits, two of which are exposed. The drift consists of till, outwash stream and lake deposits (sand and gravel), and estuarine (and lake) deposits (clay and silt). The stratigraphy and lateral distribution of the deposits are complex, but data at hand s, how that the thickest deposits, including all the estuarine and lake sediment and most of the stream-deposited sediment, are beneath the lowland away from the mountain wall, and that the deposits near the mountains are till and subordinate outwash sediments. Deposits of sand and gravel laid down by outwash streams in channels and on outwash plains are the most important aquifers, and the only ones which yield large quantities of ground water from single beds. Thin layers of sandy or gravelly material in till are also important aquifers although they yield relatively small quantities of water. Bedded sand and silt associated with the estuarine and lake(?) clay commonly becomes unstable during drilling and pumping, and has been successfully developed in only a few wells. Unconfined aquifers are extensive, but permeable saturated material is thin in many places and water supplies available from them are small or undependable in those places. The most important aquifers are confined or artesian. Clay and till form the confining beds: the till is somewhat 'leaky' in many places. Near Anchorage the buried water-bearing beds appear to be interconnected and to form a single artesian system. The water table and piezometric surface slope from the mountain wall of the lowland toward the estuaries, and the flow of the ground water is in that direction. The aquifers are recharged by the infiltration of precipitation at the land surface and of surface water through stream beds: near the mountains the artesian aquifers are probably recharged in part by percolation from the water-table aquifer, and far from the mountains the water-table aquifer is probably recharged in part by upward flow from the underlying artesian aquifers. In several valleys and in a few other places, in the lowland, artesian wells flow at the land surface. The outwash sand and gravel are moderately to very permeable; most of the other water-bearing material are much less permeable. The co- efficient of transmissibility for some single beds of sandy gravel is as high as 60,000 to I00,000 gpd per ft (gallons per day per foot); for the entire section of glacial drift at and near Anchorage it is believed to be of the order of 200,000 gpd per ft. Calculations based on this value for the total section and on the slope of the piezometric surface indicate that in the immediate vicinity of Anchorage about 5 million gpd flows through each mile-wide section of the drift (measured in a northeast-southwest direction, perpendicular to the direction of flow), under normal (nonpumping) conditions. Under conditions of continuous heavy pumping the slope of the piezometric surface is steepened, flow is increased, and additional recharge is induced. The highest yield reported from a well in this area is 2.600 gpm (gallons per minute) with 35 feet of drawdown: the highest reported specific capacity is 180 gpm per ft of drawdown, for a well pumped at. 270 gpm. Only a few wells in the area have been developed for high yields. Well screens have been used

Water Supply Paper↗
USGS1954

Geology and ground-water resources of the Matanuska Valley agricultural area, Alaska

The Matanuska Valley is a part of the lowland lying north of the Chugach Range in south-central Alaska. The valley of Matanuska River and the lowland extending westward from it to the Susitna River are in the Matanuska and Wasilla districts as defined by P.S. Smith (1939, pl. 3). The area described by this thesis, hereafter termed the Matanuska Valley agricultural area, is best known as including the site of agricultural colonization undertaken by the Federal Government in 1935. It is bounded on the north by the Talkeetna Mountains and Little Susitna River, and on the south by Knik River and Knik Arm (plate 1). It lies between Eska Creek on the northeast and Goose Bay on the southwest. As thus defined the area lies approximately between 148 °55' and 149°50' west longitude and between 61°25' and 61°45' north latitude; it covers about 350 square miles.

Alaska↗