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Jeffrey D. Phillips

Publications and source records attributed to Jeffrey D. Phillips.

31 records · Page 2Linked to original sources
USGS1993

National geophysical data grids; gamma-ray, gravity, magnetic, and topographic data for the conterminous United States

Overview and installation Note: the information on this site was copied from an optical medium publication. Although all data and software published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials. This CD-ROM has been produced in accordance with the ISO 9660 CD- ROM Standard and is therefore capable of being read on any computing platform that has appropriate CD-ROM driver software installed. However, the access software used on the disc currently executes only under DOS on IBM or compatible personal computers. OVERVIEW This CD-ROM contains gridded geophysical data, images generated from the data, software for displaying and analyzing the images, software for processing potential-field (gravity and magnetic) geophysical data, and documentation files that describe the data and software. The gridded data include gamma-ray data (uranium, thorium, and potassium channels), Bouguer gravity data, isostatic residual gravity data, aeromagnetic anomalies, topography, and topography with bathymetry. These data are available in ASCII format under the ASCII directory. This publication contains only data from the conterminous United States. The images on this CD-ROM include graytone and color images of each gridded data set, color shaded-relief images of the potential-field and topographic data, color composite images of the gamma-ray data, and color composite images of potential-field data painted on shaded and edge-enhanced topography. These images are 8-bit data and can be imported for viewing by many different software packages, but the color display tables are only designed for DOS computers and displays. The display and analysis software includes the ability to register images with geographic and geologic overlays, generate three-color composite images for display on a super VGA video system, generate perspective view images, and analyze images in five dimensions. The potential-field software on this CD-ROM can be used to extract subsets of the geophysical data, process them, and display them as images or contour maps. The software can also be used to generate gridded data from point data, generate profiles from grids, and generate geological models from gridded or profile data. This software is written in FORTRAN and, with minor modifications, can be adapted to a variety of computer systems. The documentation files reside under the directory DOSMENU\DOCFILES and are named with a suffix of DOC. This directory also contains a WordPerfect 5.1 file (CDROM.WPS) that contains all of the documentation. This CD-ROM is released in the Digital Data Series of CD-ROM's produced by the U.S. Geological Survey. This new publication series is intended to improve distribution of important earth science information to the public. The disc contains the results of work performed by the U.S. Geological Survey. INSTALLATION If you have not already done so, run the INSTALL program by making the CD-ROM drive the active drive and typing INSTALL followed by pressing the key. Follow the instructions printed on the screen. When the INSTALL program is finished, it will invoke the national geophysics (NATGP) menu program, and you will see a menu of your options. If you have previously run the INSTALL program and you have added C:\ to the PATH statement in your AUTOEXEC.BAT file, run the menu program directly by typing NATGP followed by pressing the key. If C:\ is not in your search path, you will have to type C:\NATGP followed by pressing the key. A menu of your options will appear on the screen.

Data Series↗
USGS1991

E-4 Central Kentucky to the Carolina Trough

E-4 is one of eight Geodynamics transects that cross the Atlantic margin of North America between Georgia and Newfoundland. Five of the transects are in the United States and three are in Canada. Transect E-4, which is 110 km wide and more than 1,100 km long, extends from the stable North American craton just west of the Grenville front near Lexington, Kentucky southeastward across Cape Fear, North Carolina, on the Atlantic coast to oceanic crust east of the Blake Spur magnetic anomaly. Like all of the other U.S. Atlantic coast transects, it crosses Cambrian and Jurassic continental margins of North America as well as the Appalachian orogen. The display, based upon published information, portrays the geology, tectonic style and geophysical expression of this segment of the eastern North American continental margin and interprets its Phanerozoic history. The Decade of North American Geology 1983 geologic time scale (Palmer, 1983) is used throughout the display and text.

Book↗
USGS1983

Studies related to the Charleston, South Carolina, earthquake of 1886 — Tectonics and seismicity

Since 1973, the U.S. Geological Survey (USGS), with support from the Nuclear Regulatory Commission, has conducted extensive investigations of the tectonic and seismic history of the Charleston, S.C., earthquake zone and surrounding areas. The goal of these investigations has been to discover the cause of the large intraplate Charleston earthquake of 1886, which dominates the record of seismicity in the Southeastern United States, through an understanding of the historic and modern seismicity at Charleston and of the tectonic setting of the seismicity. This goal is being pursued to evaluate the potential for additional large earthquakes in the Charleston area and surrounding regions and to determine whether the Charleston area differs tectonically in any significant fashion from other parts of the Southeastern United States. An understanding of the specific cause for the 1886 event and of the regional distribution of any structures that are generically related to or geometrically and mechanically similar to the source structure is essential for evaluation of seismic hazards throughout the Southeast. The results given herein represent significant progress toward understanding the tectonic setting of the Charleston-area seismicity. Several chapters in the volume address the distribution and origin of pre-Cretaceous rocks and structures beneath Coastal Plain sediments in the Charleston area and regionally beneath the southern Atlantic Coastal Plain and adjacent Continental Shelf. The modern seismicity at Charleston is occurring at depths equal to or greater than the known extent of these older structures, and rejuvenation of an older fault in the modern stress field is a possible cause of the seismicity. Accordingly, several chapters discuss the possible relationships of the various pre-Cretaceous structures to faults identified near Charleston that have a known Cretaceous and Cenozoic movement history and to the historic and instrumentally recorded seismicity. However, at the present time, none of the young structures can be related unequivocally to the seismicity because earthquake fault-plane solutions and hypocenter distributions do not agree with the locations and orientations of these structures. Therefore, a major emphasis of continuing USGS investigations near Charleston will be to identify additional faults, if any exist, to delineate fault movement histories, and to further refine earthquake locations, focal mechanisms, and related seismological interpretations.

Florida, Georgia, South Carolina↗
USGS1978

ADEPT: a program to estimate depth to magnetic basement from sampled magnetic profiles

A fortran program computes depth to magnetic basement from the spatially varying autocorrelation function of a sampled magnetic profile. The depth calculation assumes a particular form for the autocorrelation function, and this assumption is tested against the measured autocorrelation function in order to reject invalid depth estimates.

Open-File Report↗