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Title: Detection of karst structures using airborne EM and VLF

Abstract

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.

Authors:
 [1];  [2]
  1. Oak Ridge National Lab., TN (United States)
  2. Northern Illinois Univ., De Kalb, IL (United States)
Publication Date:
OSTI Identifier:
80256
Report Number(s):
CONF-941015-
Journal ID: ISSN 1052-3812; TRN: 95:016683
DOE Contract Number:
AC05-84OR21400
Resource Type:
Conference
Resource Relation:
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.
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ELECTROMAGNETIC SURVEYS; DATA ANALYSIS; OAK RIDGE RESERVATION; SITE CHARACTERIZATION; HYDROLOGY; CAVITIES; CAVES; TENNESSEE; MAPPING

Citation Formats

Beard, L.P. Nyquist, J.E., and Carpenter, P.J. Detection of karst structures using airborne EM and VLF. United States: N. p., 1994. Web.
Beard, L.P. Nyquist, J.E., & Carpenter, P.J. Detection of karst structures using airborne EM and VLF. United States.
Beard, L.P. Nyquist, J.E., and Carpenter, P.J. 1994. "Detection of karst structures using airborne EM and VLF". United States. doi:.
@article{osti_80256,
title = {Detection of karst structures using airborne EM and VLF},
author = {Beard, L.P. Nyquist, J.E. and Carpenter, P.J.},
abstractNote = {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.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1994,
month =
}

Conference:
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