Tectonic stress studies and seismic surveys on the West-Svalbard margin (20.5)

Introduction

Tha main goal of CAGE20-5 cruise was to continue with an Ocean Bottom Seismometer (OBS) experiment to address objectives of the SEAMSTRESS project (Tectonic stress effects on Arctic methane seepage[SB1] ). Along the eastern segment of Vestnesa Ridge, the cruise recovered 7 OBS after a one-year deployment and subsequentially redeployed 10 OBS in the larger array on the southern flank of Vestnesa Ridge. The overall aim is to detect local and regional earthquakes that relate to and/or impact local faulting within Vestnesa Ridge and may control fluid flow. Another objective of CAGE20-5 was to collect seismic lines to complete the data base and refine site selections for the IODP985 proposal. We also collected a 3D seismic volume on the elongated depression north of Knipovich Ridge where massive gas hydrates and pore fluid pressure pulses from piezometer data have been observed.