Detection of karst structures using airborne EM and VLF
Through the combined use of multi-frequency helicopter electromagnetic and VLF data, it is possible to detect and delineate a wide variety of karst structures and possibly to assess their interconnectedness. Multi-frequency EM Can detect karst features if some element of the structure is conductive. This conductive aspect may derive from thick, moist soils in the depression commonly associated with a doline, from conductive fluids in the cavity, or from conductive sediments in the cavity if these occupy a significant portion of it. Multiple loop configurations may also increase the likelihood of detecting karst features. Preliminary evidence indicates total field VLF measurements may be able to detect interconnected karst pathways, so long as the pathways are water or sediment filled. Neither technique can effectively detect dry, resistive air-filled cavities.
- Oak Ridge National Lab., TN (United States)
- Northern Illinois Univ., De Kalb, IL (United States)
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Journal ID: ISSN 1052-3812; TRN: 95:016683
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- Conference: 64. annual meeting of the Society of Exploration Geophysicists and international exposition, Los Angeles, CA (United States), 23-27 Oct 1994; Other Information: PBD: 1994; Related Information: Is Part Of SEG international exposition and sixty-fourth annual meeting -- 1994 Technical program: Expanded abstracts with authors` biographies; PB: 1736 p.
- Society of Exploration Geophysicists, Tulsa, OK (United States)
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- United States
- 54 ENVIRONMENTAL SCIENCES; ELECTROMAGNETIC SURVEYS; DATA ANALYSIS; OAK RIDGE RESERVATION; SITE CHARACTERIZATION; HYDROLOGY; CAVITIES; CAVES; TENNESSEE; MAPPING