Abstract

3-D seismic data acquisition is an important tool in Hydrocarbon exploration, and has always been a challenging task to carry out 3-D land seismic survey in logistically difficult areas. For better subsurface imaging and precise mapping, a good 3-D volume is a prime requirement with respect to fold, better offset distribution and wide azimuth. Due to increasing industrialization and urbanization, missing of source and receiver locations is rather menacingly increasing, and making the task still more complex and challenging. Ground patches of varying sizes, in the area of survey not amenable for placement of planned source and/or receivers due to various logistics need to be looked upon as obstacles in our path of seismic coverage of the given area. Seismic data acquisition encounter various types of obstructions small, big, wide, time variant, elongated, irregular shape and size. Villages, ponds, roads, oil wells can be categorized as small obstructions, where as town, industrials areas, salt pans, oil installations and time-variant obstacles such as tidal areas can be considered as major obstructions in seismic data acquisition. Data gaps due to the missed out locations, in the final processed outputs confront the processor and interpreter more or less alike, in execution of their respective studies confidently. Seismic events may not be confidently correlatable across, especially over the large data gaps. The compulsion to bridge the data gaps is thus obvious in completing the image of the subsurface below the obstacle area. This leads to the concept of filling the data gaps by recoveries, in an attempt to make the data loss good. To fill the large data gap over the larger obstructions, meticulous planning and execution are required in both technical and other logistical support aspects. This paper deals with planning and execution of recovery plans to illuminate the subsurface across the obstacles.