GENERATION OF SYNTHETIC SEISMOGRAM TO STUDY LITHOLOGICAL VARIATIONS

Abstract

By and large almost all the worlds sedimentary basin areas have yielded their buried structural secrets to the Reflection Seismograph whereas stratigraphy has only incidently or even accidently been determinable by the seismograph. The concentration of efforts towards structural features, in the past, could be because they are easier to find as comwared to the stratigraphic traps, and also because they extend vertically through thick sections of productive rocks (which actually yielded a large quantity of oil) whereas etratigraphic traps are confined to an individual stratigraDDhic level. Moreover, even in stratigraphic deposits, often structure plays an important role. But since 'structural Oil' was found to supply the worlds needs more than adequately, in the past, no harm was done. However, now, the time is at hand with an escalating demand for oil and the enormous cost involved in drilling dry holes (usually about 8 out of the 9 holes drilled are dry) , that the stratigraphic informa-tion is a must for a more successful exploration effort. It is also believed that the stratigraphic traps outnumber structural traps by almost 2:1 (Lyons, 1968) . And the great size of some of the stratigraphic traps discovered in U.S.A. have led the scientists there to believe that they may outetop structural traps in ultimate reserves (Lyone, 1968). Thus with the promise of large future reserves there is a great deal of interest in obtaining strati raphic information. Basically, the stratigraphic information has to be about different kinds of rocks. If the Reflection seismograph is to distinguish one rock from another, it must be by displaying different kinds of reflections, One of our problems in the past had been that we often could not tell one reflection from another, so obviously we could not toll one reflector (or rock kind) from another, by looking at a set of identical reflections.....