ISSN:
1420-9136
Keywords:
Key words: Optical fibers, strainmeters, benchmarks.
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract —We have developed and operated optical fiber interferometers for monitoring displace ments within boreholes, as part of a program of crustal deformation measurement. These optical fiber strainmeters—a total of twelve instruments at two sites in southern California—were installed to sense the motion of the end-monuments of much longer baseline strainmeters and tiltmeters, allowing correction for any near-surface ground movement. One of the installations was specifically designed to investigate the distribution of deformation with depth, measuring over several borehole length-intervals from 5 m to 50 m. The displacements recorded over year-long time scales along these length intervals range up to 6 mm and show internal consistency and stability at the 50 μ m level. The use of these interferometers to provide correction signals for kilometer-scale crustal strain measurements has resulted in greatly improved records.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s000240050152
Permalink