A low-frequency passive seismic array experiment over an onshore oil field in Abu Dhabi, United Arab Emirates

ABSTRACTA low-frequency passive seismic experiment using an array of 49 3C broadband seismometers was conducted over an onshore oil field in the emirate of Abu Dhabi in the United Arab Emirates. The aim of the experiment was to understand the characteristics and origins of the microseism (0.15–0.4 Hz) and microtremor (about 1–6 Hz) signals recorded, the latter having been reported as being a hydrocarbon indicator above several reservoirs in the region. The recorded array data were analyzed for their polarization, apparent velocities, and wavefront azimuths using various techniques, including spectral and time-frequency analyses, particle motion, H/V spectral ratios, and high-resolution frequency-wavenumber (f-k) analyses. In the frequency range of 0.15–0.4 Hz, the dominant feature observed consisted of double-frequency microseisms peaks generated by the nonlinear interactions of ocean waves with the shoreline along the coasts of the Arabian Sea and the Arabian Gulf. The f-k analyses confirmed that microtr...