Marine EM Studies over Scarborough Gas Field

Scripps Institution of Oceanography is a world leader in the development of marine electromagnetic methods, starting with the pioneering work of Charles Cox and Jean Filloux in the 1970’s (e.g. Cox, Filloux, and Larsen, 1971), continuing from the early 1980’s with the work of Steven Constable, and now with the recruitment of Kerry Key onto the permanent scientific staff. Initially marine EM methods were developed for the study of the deep seafloor and mid-ocean ridges in particular, and this application continues to this day, but in the mid 1990’s Constable and Key (then a graduate student) started to apply marine EM methods to offshore exploration problems. Initially the research focussed on the development of marine magnetotelluric (MMT) methods to assist interpretations in seismically difficult terrane such as salt, basalts, and carbonates (Constable et al., 1998; Key, Constable, and Weiss, 2006). Later, Scripps played a critical role in the development of marine controlled-source electromagnetic (MCSEM) sounding for direct detection of hydrocarbons (Ellingsrud et al., 2002; Constable, 2006; Constable and Srnka, 2007). Most recently, Scripps is developing equipment and methodology to use EM to map shallow hazards such as gas hydrate and shallow gas (Weitemeyer et al., 2006; Weitemeyer, Constable, and Key, 2006). Future applications may include the monitoring of oil and gas reservoirs during production using marine EM methods (Orange, Key, and Constable, 2009).