New borehole installations in Taiwan and Korea

New borehole installations in Taiwan and Korea

January 21

With the recent installation of more than twenty borehole seismometers in Taiwan and Korea, Guralp Systems is continuing its role as the world leader in manufacturing and deploying seismic broadband instrumentation for both shallow and deep boreholes.  In early December two installation teams from our headquarters in the UK spent almost two weeks in Taiwan to deploy a total of ten instruments in boreholes with depths ranging from 200 to 400 meters.  These instruments consisted of six sensors each, a three component CMG-3TB broadband seismometer and a CMG-5TB tri-axial accelerometer.  All six sensors were combined into one borehole package with typical diameter of 89 millimeters.  The customer, Taiwan’s Central Weather Bureau (CWB), is using these borehole sensors to augment its extensive seismic monitoring network.

The Korean Meteorological Administration (KMA) took a similar approach in ordering twelve CMG-3TB borehole seismometers for their existing network, which currently comprises more than 110 surface stations.  The first of these sensors was recently installed on the premises of an elementary school in the town of Okcheon in the central part of Korea in a 95 meter deep borehole (station OKCB).

These two projects are part of a growing trend among institutions monitoring seismic activity.  More and more of them are starting to use borehole instruments in their respective networks.  The main reason for going below ground is that unwanted seismic noise decreases with depth.  Hence, adding borehole sensors to a network will usually increase its detection level.  Such a gain can be especially pronounced in densely populated countries like Korea and Taiwan.

Both recent installations would not have been possible without the close cooperation with GSL’s partners and distributors, San Lien in Taiwan and Heesong Geotek in Korea.  Our partners not only negotiated the respective contracts with our customers, but they were also essential in organizing the drilling of the boreholes, building the necessary infrastructure and providing the all important logistical support during the installation procedure.

Two very different installations

Two very different installations

Since its founding in 1985, Guralp Systems has been developing, building and deploying sensors and digitizers for installations in boreholes on land as well as on the seabed (Ocean Bottom Borehole Systems).  Our product families range from pure analogue sensors to systems combined with down-hole digitizers.  We also offer data transfer to the well head by optical fiber.  All of our down-hole systems can be installed in dry or wet boreholes, be they shallow or over a thousand meters deep.  In order to optimize the coupling between the sensor and the well casing, we recommend to always use our unique hole locks.  They can be adapted to borehole diameters of almost any size and allow the retrieval of the sensor, even in those rare cases when the down-hole power to the instrument fails completely.

For more information,  email sales@ideaasgroup.com  or call 905 882 3095

Leave a Comment

Your email address will not be published. Required fields are marked *