Electrical and Computer Engineering ETDs
Publication Date
2-22-1978
Abstract
Current practices in geothermal research require electrical prospecting methods such as resistivity mapping and profiling. This project was predicated on the need for an improved measurement technique for performing dc resistivity mapping at the earth's surface. A synchronous detection system provides automatic detection, recording, and flexible control for the signal current source used in resistivity mapping. As a part of this project, a synchronous detection system was designed, fabricated, and tested. The system incorporates a noise suppression scheme using the frequency-modulated spectrum of the noisy signal. The overall system, which includes a Synchronous Transmitter Control, a Synchronous Detector, and a Synchronous Programmer, is shown to be a significant improvement over presently available equipment. It is capable of measuring transmitted square wave signals in a noisy environment and at considerable distances from the transmitter. The organization of the entire system, as well as the detailed operation of each of the three units are discussed. A complete set of schematic diagrams is presented along with the raw test data which compares the synchronous system with the strip chart recorders commonly used.
Document Type
Thesis
Language
English
Degree Name
Electrical Engineering
Level of Degree
Masters
Department Name
Electrical and Computer Engineering
First Committee Member (Chair)
Ahmed Erteza
Second Committee Member
Ruben David Kelly
Third Committee Member
Roy Arthur Colclaser
Recommended Citation
Olsen, Stewart Lee. "A Synchronous Detection System for dc Resistivity Mapping at the Earth's Surface." (1978). https://digitalrepository.unm.edu/ece_etds/621