While land point source and point receiver acquisition is gaining acceptance in certain regional and geological settings its uptake in Latin America has been limited. Historically the industry has tried to solve the problems of surface noise on land seismic surveys by increasing source and receiver effort by using large arrays and by sending lots of signal energy into the ground. Point source and receiver techniques attempt to resolve the problems associated with the complex noise field on land surveys in a more scientific way, by measuring the linear noise modes as faithfully as possible i.e. un-aliased or not disturbed by the use of geophone arrays. In 2007 WesternGeco acquired a point receiver 2D survey at the base of the Al-Hajar mountain range close to Dubai in the UAE at the edge of the Oman thrust belt. The geology is very complex with steeply dipping structure. The survey was acquired on top of a 2003 3D survey out the two acquisitions used radically different approaches, some of which are detailed in table 1. In addition to the use of point receivers and compact source groups, the bandwidth of the sweep was extended at the low end. The final 2007 PSDM images showed significant uplift above the 2003 PSTM processing. The signal to noise is much better, to the point where it is possible to interpret the structural geometry with some level of confidence. It is difficult to draw absolute conclusions when comparing the 2003 time image with the 2007 depth image because of the use of a depth imaging solution. However, the uplift in the pre-imaging measurement will not only benefit the imaging solution but all additional processes, most specifically the velocity modeling which is critical to the depth imaging effort. The combination of all these incremental uplifts can result in significant overall improvement in imaging quality.


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