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Title: Delineation of an old coal mine in an urban environment with surface wave seismics using a landstreamer and laterally constrained inversion

Abstract

Prior to the site investigation for a tunnel below Helsingborg, southern Sweden, a surface wave seismic investigation was made to delineate an old coal mine. The mine as described in old literature has an area of about 6 acres and each layer of coal has a height of less than one 1 m; however, the exact location and status is unclear. The sedimentary geological setting consists of fill, quaternary deposits, shale, coal and sandstone. The mine, or alternatively the coal, is found at 10 m depth between a layer of shale and a layer of soft sandstone. The seismic measurements were made along two crossing profiles, located on the walkways covered with gravel, in the area where the mine is expected. The measurement system was a landstreamer with 244.5 Hz geophones, a Geometrics Geode and a shotgun. The v{sub s} models clearly show increasing velocities with depth with a low velocity layer at 10 m depth. The results correlate well with the expected geology and results from geotechnical drillings that indicate an open mine in parts of the area; however, the low velocity layer is mainly due to the soft sandstone and does not seem to be strongly affected bymore » the presence of the open mine.« less

Authors:
; ;  [1]
  1. Tyrens AB, Helsingborg (Sweden)
Publication Date:
OSTI Identifier:
21149663
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proceedings of Symposium on the Application of Geophysics to Engineering and Environmental Problems; Journal Volume: 20; Journal Issue: 1; Conference: 20. symposium on the application of geophysics to engineering and environmental problems, Denver, CO (USA), 1-5 Apr 2007
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL MINES; SEISMIC WAVES; SEISMIC SURVEYS; DEPTH; COAL SEAMS; VELOCITY; SURFACE MINING; ABANDONED SHAFTS; MAPPING

Citation Formats

Roger Wisen, Mattias Linden, and Mats Svensson. Delineation of an old coal mine in an urban environment with surface wave seismics using a landstreamer and laterally constrained inversion. United States: N. p., 2007. Web.
Roger Wisen, Mattias Linden, & Mats Svensson. Delineation of an old coal mine in an urban environment with surface wave seismics using a landstreamer and laterally constrained inversion. United States.
Roger Wisen, Mattias Linden, and Mats Svensson. Mon . "Delineation of an old coal mine in an urban environment with surface wave seismics using a landstreamer and laterally constrained inversion". United States. doi:.
@article{osti_21149663,
title = {Delineation of an old coal mine in an urban environment with surface wave seismics using a landstreamer and laterally constrained inversion},
author = {Roger Wisen and Mattias Linden and Mats Svensson},
abstractNote = {Prior to the site investigation for a tunnel below Helsingborg, southern Sweden, a surface wave seismic investigation was made to delineate an old coal mine. The mine as described in old literature has an area of about 6 acres and each layer of coal has a height of less than one 1 m; however, the exact location and status is unclear. The sedimentary geological setting consists of fill, quaternary deposits, shale, coal and sandstone. The mine, or alternatively the coal, is found at 10 m depth between a layer of shale and a layer of soft sandstone. The seismic measurements were made along two crossing profiles, located on the walkways covered with gravel, in the area where the mine is expected. The measurement system was a landstreamer with 244.5 Hz geophones, a Geometrics Geode and a shotgun. The v{sub s} models clearly show increasing velocities with depth with a low velocity layer at 10 m depth. The results correlate well with the expected geology and results from geotechnical drillings that indicate an open mine in parts of the area; however, the low velocity layer is mainly due to the soft sandstone and does not seem to be strongly affected by the presence of the open mine.},
doi = {},
journal = {Proceedings of Symposium on the Application of Geophysics to Engineering and Environmental Problems},
number = 1,
volume = 20,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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