A Low Frequency Passive Seismic Array Experiment Over an Oilfield in Abu Dhabi – Implications for Hydrocarbon Detection

A low frequency passive seismic experiment utilising an array of forty-nine 3-component broadband seismometers were conducted over an oilfield in the emirate of Abu Dhabi in the United Arab Emirates (UAE). The experiment was conducted to better understand the characteristics and origins of microtremor signals (1–10 Hz) which had been reported as occurring exclusively above several hydrocarbon reservoirs in the region. High resolution frequency-wavenumber (f-k) spectral analyses were performed on the recorded array data to determine apparent velocities and azimuths of the wavefronts for the microseism and microtremor events. The f-k analyses confirmed that the microtremor events have an azimuth pointing towards a major oil pipe line west of the study area and a motorway east of the study area, indicating that they are probably being excited by continuous movement of the oil through the pipeline and by traffic noise. No body waves with an infinite apparent velocity were observed.