NEHRP Clearinghouse

Title
Borehole Dilatometer Installation, Operation, and Maintenance at Sites in Hawaii.
File
PB2007101866.pdf
Author(s)
Myren, G. D.; Johnston, M. J. S.; Mueller, R. J.
Source
January 2006, 113 p.
Identifying Number(s)
USGS/OFR-2006-1103
Abstract
In response to concerns about the potential hazard of Mauna Loa volcano in Hawaii, the USGS began efforts in 1998 to add four high-resolution borehole sites. Located at these sites are; strainmeters, tiltmeters, seismometers, accelerometers and other instrumentation. These instruments are capable of providing continuous monitoring of the magma movement under Mauna Loa. Each site was planned to provide multi-parameter monitoring of volcanic activity. The purpose of this network is to monitor crustal deformation associated with volcanic intrusions and earthquakes on Mauna Loa and Kilauea volcanoes. This report describes the methods used to locate sites, install dilatometers, other instrumentation, and telemetry. We also provide a detailed description of the electronics used for signal amplification and telemetry, plus techniques used for instrument maintenance. Instrument sites were selected in regions of hard volcanic rock where the expected signals from magmatic activity were calculated to be a maximum and the probability of earthquakes with magnitude 4 or greater is large. At each location, an attempt was made to separate tectonic and volcanic signals from known noise sources for each instrument type.
Keywords
Measuring instruments; Telemetry; Installation; Maintenance; Volcanoes; Satellite telemetry configurations; Boreholes; Operation; Drilling; Surface electronics; Soil properties; Barometers; Dilatometers; Hawaii; Siting; Borehole dilatometers