Accession Number:

ADA455074

Title:

SeisCORK Meeting Report

Descriptive Note:

Technical memorandum

Corporate Author:

WOODS HOLE OCEANOGRAPHIC INSTITUTION MA DEPT OF GEOLOGY AND GEOPHYSICS

Personal Author(s):

• Stephen, R. A.
• Pettigrew, T.
• Becker, K.
• Spiess, F.

Report Date:

2006-02-01

Pagination or Media Count:

36.0

Abstract:

The purpose of this meeting was to explore design options to simultaneously acquire borehole seismic data and hydro-geological data pressure, temperature, fluid sampling and microbiological sampling on a single CORK system. The scientific focus was to add a seismic component to the Juan de Fuca Hydrogeology program. By permanently installing a sensor string in the borehole our goal was to enable 1 time-lapse VSPs and offset VSPs with sufficient data quality to study amplitude versus offset, shear wave anisotropy, and lateral heterogeneity 2 monitoring of micro- and nano- earthquake activity around the site for correlation with pressure transients. Because of the difficulty in ensuring adequate coupling through multiple casing strings we concluded that it was impractical to install the vertical seismic array with 10m spacing 50-60 nodes that would be necessary for VSPs and time-lapse VSPs. We did describe a scenario for a vertical seismic array with approximately 100m spacing 5-6 nodes that could be used for offset-VSPs and seismic monitoring. This uses some unique technology and involves two seismic strings one in the annulus between the 4-12 and 10-34 casings and one in the middle of the 4-12 casing.

Descriptors:

• *BOREHOLES
• *SEISMIC DATA
• *HYDROGEOLOGY
• MONITORING
• EARTHQUAKES
• DESIGN CRITERIA

Subject Categories:

• Seismology
• Seismic Detection and Detectors
• Hydrology, Limnology and Potamology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE