| Bohai segment of the Tan-Lu strike-slip fault zone is the main production area of the oil and gas in Bohai oil field. Statistics research currently show that nearly 65% of crude oil reserves, nearly 80% of gas reserves found in Bohai Oilfield are all located along the Tan-Lu fault zone. Tectonic movement and hydrocarbon accumulation distribution pattern on the Tan-Lu fault zone is one of the hot topics of china petroleum geological research. In this paper, based on extensive literature investigation and quantities of comprehensive study on tectonic development feature and reservoir-forming rule of the Tan-Lu fault zone by means of seismic structure interpretation, reservoir mechanism analysis and areal geology, the following main conclusions can be drawn:1) By using a large number of geological and geophysical data,We made a systematic study on the structural geology of Bohai Sea region and the evolution deformation characteristics of the Tan-Lu Fault Zone. Studies have shown that the Tan-Lu fault zone in Bohai region has clear characteristics of zonation, segmentation, hierarchical differences in deformation, it says, northern, central, and southern sections. In addition we analyzed the activity characteristics of each section in different geological periods; The combined feature and the relationship between the main fault and derived fault has been derived. Finally, It Points out that the favorable sites to the development of parts of structure trap is sinistral right-step fault zone of the Tan-Lu fault zone, trap (base) scale is proportional to the scale of sinistral strike-slip; 2) Base on fine dissection of trap types and genetic mechanism of the large and medium sized traps (oilfield) along the Tan-Lu fault zone, the trap will be divided into two traps, one of which is formed by extensional regime , the other strike slipping effects, the former mainly acts in the Paleogene, the latter mostly occurs in the late Neogene-Quaternary; 3) Analyze and summarize the mechanism and mode of extensional tectonic system and strike slip tectonics system interaction, Three major modes is be first proposed.①strike slipping controled depression mode (pinnate model)②"H"-type dynamic mechanism system model③"U "-type complex superimposition mode; 4) Comprehensive application of evolution of the mature of the organic matter, three-dimensional simulation of migration pathways, source rock hydrocarbon generating and expulsion threshold analysis technique to ease combing and analysis petroleum accumulation condition and fracture grooming system for the Tan-Lu fault zone (Bohai segment) ,and that it has nearly source reservoir, sustainable for hydrocarbons, transmission efficiency, natural earthquake-driven, episodic petroleum accumulation infill injection, and quality caprock of oil and gas accumulation geological elements , possess the formation of high-quality medium-sized oil and gas fields of the favorable conditions. The relationship between Tan-Lu strike-slip activities and the special conditions of its accumulation are discussed.; 5) Applying a variety of fracture characterization techniques of quantitative semi-quantitative method to characterization of fault activity, efforts on combined analysis on fracture, overflow location, the relationship of fault throw and the thickness of cap rocks points out the facts that the Tan-Lu fault zone (Bohai segment) differences control oil of the fault activity, and oil and gas enrichment horizon could reveal the enrichment section and enrichment degree from north to south distribution; 6) By Tan-Lu fault zone along the fine and medium-sized oil and gas fields of anatomy and new tectonic movement and fracture grooming system of relations and to ease the high accumulation model of the summary analysis, the unique characteristics on accumulation of oil and gas dynamic balancing reservoir of the bohai bay basin under the new tectonic movement conditions is present. Five enrichment patterns are classified by the differences in temporal activities of Tan-Lu fault zone. |
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