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Jared D. Abraham

Publications and source records attributed to Jared D. Abraham.

21 records · Page 2Linked to original sources
USGS2002

Directional borehole radar tests of an oil injection experiment at the Colorado School of Mines, Golden, Colorado

In October 2001, the U.S. Geological Survey conducted borehole radar surveys of an oil injection experiment at the Colorado School of Mines (CSM), in Golden Colorado using the prototype U.S. Geological Survey (USGS)-developed directional borehole radar system (DBOR). A explanation of the system can be found in Wright and others (2001). The USGS was invited to the CSM to deploy the prototype directional borehole radar system during an oil injection experiment conducted to investigate the applicability of radar to monitoring formation invasion from a horizontal borehole. This work was conducted by a student at the CSM and is summarized in Moita (2001). The purpose of this report is to release the data and to summarize the experiments conducted with the DBOR system. This report contains, (1) a description of the system as deployed in the experiments, (2) a description of the data collected and data parameters used, (3) a simple display of some of the data collected, and (4) a description of the DBOR data files.

Colorado↗
USGS2000

Imaging and modeling new VETEM data

In previously reported work (Wright and others, 2000) we found that the very early time electromagnetic (VETEM) prototype system produced data from which high resolution images of a buried former foundry site at the Denver Federal Center were made. The soil covering the site is about 30 mS/m conductivity, and is thus relatively unfavorable for ground penetrating radar (GPR) imaging. We have surveyed portions of this site again with new electric field dipole antennas and a new receiver designed for these antennas. Comparisons of the images produced using the loop antennas to those produced using the electric field dipole antennas illustrate that for this application the loop antennas produced more useful images. The larger man-made structures can be seen more clearly because they are not masked by dispersion and/or smaller scale variations as with the electric field dipole antennas. The VETEM system now contains an array of antennas with appropriate transmitters and receivers and can be operated as a low frequency time domain GPR or as a high frequency time domain electromagnetic (EM) system with several possible antenna spacings and polarizations. We plan to examine additional configurations. Numerical modeling of the perpendicular loop antenna configuration has been done and depth estimates produced. We conclude that, as with other GPR and time domain EM systems, the best choice of operating parameters depends on the application and the environment, but the inherent flexibility of the VETEM system allows a wide range of options.

Conference Paper↗