On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System
X-ray computed tomography (CT) is an established technique for nondestructively characterizing geologic cores. CT provides information on sediment structure, diagenetic alteration, fractures, flow channels and barriers, porosity, and fluid-phase saturation. A portable CT imaging system has been deve...
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ftcdlib:qt6xj835nh 2023-05-15T17:12:05+02:00 On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System Freifeld, Barry M. Kneafsey, Timothy J. Rack, Frank 2004-03-01 application/pdf http://www.escholarship.org/uc/item/6xj835nh english eng eScholarship, University of California qt6xj835nh http://www.escholarship.org/uc/item/6xj835nh public Freifeld, Barry M.; Kneafsey, Timothy J.; & Rack, Frank. (2004). On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System. Lawrence Berkeley National Laboratory. Lawrence Berkeley National Laboratory: Lawrence Berkeley National Laboratory. Retrieved from: http://www.escholarship.org/uc/item/6xj835nh Earth Sciences article 2004 ftcdlib 2016-04-02T18:30:08Z X-ray computed tomography (CT) is an established technique for nondestructively characterizing geologic cores. CT provides information on sediment structure, diagenetic alteration, fractures, flow channels and barriers, porosity, and fluid-phase saturation. A portable CT imaging system has been developed specifically for imaging whole-round cores at the drilling site. The new system relies upon carefully designed radiological shielding to minimize the size and weight of the resulting instrument. Specialized x-ray beam collimators and filters maximize system sensitivity and performance. The system has been successfully deployed on the research vessel Joides Resolution for Ocean Drilling Program's Leg 204 and 210, within the Ocean Drilling Program's refrigerated Gulf Coast Core Repository, as well as on the Hot Ice #1 drilling platform located near the Kuparuk Field, Alaska. A methodology for performing simple densiometry measurements, as well as scanning for gross structural features, will be presented using radiographs from ODP Leg 204. Reconstructed CT images from Hot Ice #1 will demonstrate the use of CT for discerning core textural features. To demonstrate the use of CT to quantitatively interpret dynamic processes, we calculate 95 percent confidence intervals for density changes occurring during a laboratory methane hydrate dissociation experiment. The field deployment of a CT represents a paradigm shift in core characterization, opening up the possibility for rapid systematic characterization of three-dimensional structural features and leading to improved subsampling and core-processing procedures. Article in Journal/Newspaper Methane hydrate Alaska University of California: eScholarship |
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University of California: eScholarship |
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Earth Sciences Freifeld, Barry M. Kneafsey, Timothy J. Rack, Frank On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
topic_facet |
Earth Sciences |
description |
X-ray computed tomography (CT) is an established technique for nondestructively characterizing geologic cores. CT provides information on sediment structure, diagenetic alteration, fractures, flow channels and barriers, porosity, and fluid-phase saturation. A portable CT imaging system has been developed specifically for imaging whole-round cores at the drilling site. The new system relies upon carefully designed radiological shielding to minimize the size and weight of the resulting instrument. Specialized x-ray beam collimators and filters maximize system sensitivity and performance. The system has been successfully deployed on the research vessel Joides Resolution for Ocean Drilling Program's Leg 204 and 210, within the Ocean Drilling Program's refrigerated Gulf Coast Core Repository, as well as on the Hot Ice #1 drilling platform located near the Kuparuk Field, Alaska. A methodology for performing simple densiometry measurements, as well as scanning for gross structural features, will be presented using radiographs from ODP Leg 204. Reconstructed CT images from Hot Ice #1 will demonstrate the use of CT for discerning core textural features. To demonstrate the use of CT to quantitatively interpret dynamic processes, we calculate 95 percent confidence intervals for density changes occurring during a laboratory methane hydrate dissociation experiment. The field deployment of a CT represents a paradigm shift in core characterization, opening up the possibility for rapid systematic characterization of three-dimensional structural features and leading to improved subsampling and core-processing procedures. |
format |
Article in Journal/Newspaper |
author |
Freifeld, Barry M. Kneafsey, Timothy J. Rack, Frank |
author_facet |
Freifeld, Barry M. Kneafsey, Timothy J. Rack, Frank |
author_sort |
Freifeld, Barry M. |
title |
On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
title_short |
On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
title_full |
On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
title_fullStr |
On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
title_full_unstemmed |
On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System |
title_sort |
on-site geologic core analysis using a portable x-ray computed tomographic system |
publisher |
eScholarship, University of California |
publishDate |
2004 |
url |
http://www.escholarship.org/uc/item/6xj835nh |
genre |
Methane hydrate Alaska |
genre_facet |
Methane hydrate Alaska |
op_source |
Freifeld, Barry M.; Kneafsey, Timothy J.; & Rack, Frank. (2004). On-Site Geologic Core Analysis Using a Portable X-ray Computed Tomographic System. Lawrence Berkeley National Laboratory. Lawrence Berkeley National Laboratory: Lawrence Berkeley National Laboratory. Retrieved from: http://www.escholarship.org/uc/item/6xj835nh |
op_relation |
qt6xj835nh http://www.escholarship.org/uc/item/6xj835nh |
op_rights |
public |
_version_ |
1766068842840195072 |