 |
| Titel |
Earth conductivity structures and their effects on geomagnetic induction in pipelines |
| VerfasserIn |
P. A. Fernberg, C. Samson, D. H. Boteler, L. Trichtchenko, P. Larocca |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 25, no. 1 ; Nr. 25, no. 1 (2007-02-01), S.207-218 |
| Datensatznummer |
250015772
|
| Publikation (Nr.) |
 copernicus.org/angeo-25-207-2007.pdf |
|
|
|
|
|
| Zusammenfassung |
| Anomalous, large pipe-to-soil potentials (PSP) have been observed along a
natural gas pipeline in eastern Ontario, Canada, where there is a major
geological contact between the highly resistive rocks of the Precambrian
Shield to the west and the more conductive Paleozoic sediments to the east.
This study tested the hypothesis that large variations of PSP are related to
lateral changes of Earth conductivity under the pipeline. Concurrent and
co-located PSP and magnetotelluric (MT) geophysical data were acquired in
the study area. Results from the MT survey were used to model PSP variations
based on distributed-source transmission line theory, using a
spatially-variant surface geoelectric field. Different models were built to
investigate the impact of different subsurface features. Good agreement
between modelled and observed PSP was reached when impedance peaks related
to major changes of subsurface geological conditions were included. The
large PSP could therefore be attributed to the presence of resistive
intrusive bodies in the upper crust and/or boundaries between tectonic
terranes. This study demonstrated that combined PSP-MT investigations are a
useful tool in the identification of potential hazards caused by
geomagnetically induced currents in pipelines. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|