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Ground water hydraulics as a geophysical aid
The publication of the non-equilibrium formula in 1935 in a paper by Theis marked the opening of a new era in the analysis and understanding of the hydraulics of percolating ground waters. Through the past decade 9 an ever-increasing number of engineers and geologists have become familiar-with the application of this formula to practical problems of ground-water flow and have tested it in the field, against precise observations, under controlled conditions. Although the highly idealized aquifer assumed for the derivation of this formula is not of widespread occurrence in the field, we gain increasing confidence in the use of the Theis method as our backlog of proven data accumulates until we now look askance at test data which do not conform to this theory. In many cases, careful study of these anomalous data will reveal the means for estimating the degree or manner in which an observed aquifer diverges from the idealized aquifer.
Advancing electrical geophysical characterization of DNAPL-contaminated fractured rock aquifers
No abstract available.
Geophysical setting of the Pahute Mesa - Oasis Valley region, southern Nevada
No abstract available.
Geophysical evidence for late Cenozoic subglacial volcanism beneath the West Antarctic ice sheet and additional speculation as to its origin
No abstract available.
Detailed correlation of lithostratigraphic and borehole geophysical log data for identifying contacts at Yucca Mountain
No abstract available.
Results of integrated surface-geophysical studies for shallow subsurface fracture detection at three New Hampshire sites
No abstract available.
Use of processed geophysical data to improve the delineation of infilled scour holes at bridge piers
No abstract available.
Application of borehole geophysics at the Retsof salt mine collapse site, Western New York
No abstract available.
Marine geological and geophysical investigations in the Ross Sea, Antarctica
No abstract available.
The Holbrook Lineaments: The geophysical boundary zone between the Proterozoic Mazatzal and Yavapai Provinces, southwest USA
A horizontal gradient analysis of the isostatic gravity and aeromagnetic anomaly grids of the NewMexico-Arizona-southernCalifornia area was carried out, focused on eastern Arizona and western New Mexico, to define the transitional boundary between the Proterozoic Yavapai province to the west and the Mazatzal province to the east. The two provinces differ substantially in their favorability to host Laramide porphyry copper deposits. The gravity field anomaly displays the most continuous lineaments delineating the transitional boundaries between the two provinces. The magnetic anomaly data confirm the boundaries but are less continuous. Inferred left lateral offset and termination of the boundary zone in the southern Basin and Range suggest that the Jurassic Mojave-Sonora megashear may extend over much of the southern Basin and Range in southeast Arizona.
Airborne geophysical characterizationof geologic structure in a mountain headwater system, upper East River, Colorado
Geologic controls on groundwater flow, particularly in tectonically and topographically complex mountainous terrain, can be difficult to quantify without a detailed understanding of the regional subsurface geologic structure. This structure can influence the magnitude of groundwater flow through the mountain block, which in turn impacts groundwater composition and the flux of metals and nutrients to the near - surface ecosystem. In support of several ongoing studies in the upper East River and surrounding w atersheds in central Colorado, regional - scale airborne electromagnetic, magnetic, and radiometric survey s were conducted in late 2017 . These data give a view of the geologic structure underlying the region that is unprecedented in both resolution and spa tial coverage.
Satellite geological and geophysical remote sensing of Iceland — Preliminary results from analysis of MSS imagery
No abstract available.