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The Bukhara-Khivan region, one of the main oil-gas provinces in Uzbekistan tectonically is located at east margin of Turanian Plate. The deposits stratigraphy as major hydrocarbons production is dated as upper Jurassic. New traps and deposits of oil and gas discovered in this region (even though exploration efforts decrease in the period), trigger our detailed research on the deeper geology-geophysical structure to map the upper Jurassic carbonate and lower-middle Jurassic terrigenous sediments. We summarize the study in the following four parts:
1) I compiled the partition section of the Jurassic layer as the unit of cycle-stratigraphical complexes (CC). Where, I developed a new processing technique for the cycle-stratigraphical partition from the bore-hole homogeneous sections. In this way, four CC(s) were recognized within one terrigenous formation, and two CC(s) were recognized within one carbonate formation. Additionally, more fine partitions on the three sub-complexes (under-reef, reef and above-reef) were studied.
2) Spectral analysis of well-log diagrams is used to characterize each CC. The feature variations of amplitude-frequency analyses from well-log diagrams with the meaning of aprioristic geology permit us to study the formation and tectonic evolution of the Jurassic sedimentation basin in the scale of our research area. As the result, we infer that formation of the Jurassic sedimentation basin in Bukhara-Khivan region endured four stages of geological processes which can be demonstrated by distinctly characteristics in spectral parameters after well-log diagrams' amplitude-frequency analyses.
3) Seismic stratigraphy was analysized on CDP two-way-traveltime seismic cross section then seismic wave-field numerical modeling was made in order to realize the Jurassic section partition of seismic stratigraphical complexes and seismic facial zones. The results show strong lateral heterogeneity features including anticline structures, clinoform packs, sand bars and reef massifs in seismic facial zones. After that the perspective sites were predicted for the potential discoveries of new oil/gas traps and deposits.
4) Within the zones with strong lateral heterogeneities which are consistent with both tapering out of separate layers and facial transition between different types of lithology, I constructed the corresponding geology-geophysical models and synthetic time cross sections for clinoform complexes, zone of unconformable adjacent layers to the pre-Jurassic surfaces, erosive sheared, along coast sand bar and reef.
These geology-geophysical models and models of synthetic wave fields essentially improve seismic interpretation reliability by system test of lateral heterogeneities and classification of non-anticline oil/gas trap types.
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