Broadband Re-Processing of Vintage Mediterranean 3D Seismic: Improving the Imaging of Jurassic Limestones beyond Technical and Geological Challenges

Abstract

Summary Over the recent years, in a context of oil price instability faced by resiliently-high operational costs, all exploration risks need justification via thorough analysis performed on all the available data. In such contingency, re-processing with modern techniques all the accessible seismic surveys, even if very old, helps to retrieve the maximal information on the subsurface, fostering the decision-making process and the de-risking of successful exploration activities. The main objective of the presented study is the broadband processing of a technically- and geologically-challenging vintage marine 3D dataset from the Mediterranean Sea, via modern Pre-Stack Time Migration. The main geological target for the reprocessed dataset is represented by fractured Jurassic limestones. Severe seismic challenges are posed by the obsolete and unconventional acquisition pattern, along with the multiples and reverberations offered to the seismic image by the shallow-tilting and high-impedance Messinian salt/evaporites. The authors hereby present a modern, innovative, and rigorous broadband re-processing for the improved imaging and illumination of the subsurface, applicable to all Mediterranean provinces.