Broadband seismic recording of various signals at Eskdalemuir Array (EKA)

Sheila Peacock*1

1AWE Blacknest, Brimpton, Reading RG7 4RS,

The Eskdalemuir Array EKA is an auxiliary station of the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO). Broadband seismometers were installed at the twenty array sites in 2008.  In 2015 they recorded signals presumed to be from airguns being used in the marine seismic survey of the central North Sea commissioned by the UK Oil and Gas Authority. They also pick up acoustic signals, some of which can be attributed to supersonic aircraft manoeuvres.  Three new 3-component broadband stations equipped with hybrid-response seismometers began sending data to the CTBTO in 2017 (although only EKB is available from the CTBTO as yet).  The hybrid response is flat to velocity at frequencies between 0.04 and 2 Hz and to acceleration at frequencies on either side.  The wide bandwidth allows local and regional as well as teleseismic signals from large and small sources to be recorded. Spectrograms show curious long-duration narrow-band noise.

©British Crown-owned Copyright 2018 (AWE)