Transfer Structure And Its Petroleum Significance Of Jiyang Depression

Transfer structures developed during the extension process during Cenozoic. Based onthe comprehensive analysis of seismic profiles, coherence slices, structure isoclines map,sedimentary facieses, logging data,et al, referring to the identification principle and method,the Cenozoic transfer structures and their geometry features were identified, then thecategory schemes were founded. The kinematics features were quantitatively analyzed by themethod of fault throw, activity rate, transfer degree（k=lt/lm）and balanced cross section. Theformation and evolutionary process were restored and the distributions of different phaseswere made sure. Referring to the regional structural background, the formation mechanismwas made definite. Based on the hydrocarbon geologic settings and reservoir cases of transferstructures, the relationships between transfer structures and reservoir formation wereanalyzed, and the models were established. The conclusions can be stated as follows:The Cenozoic structures were formed by the comprehensive controls by the"concave-convex" basement structure, the former Mesozoic fault system, the stress fieldtransformation and the local block elongation. Under these controls, the1st,2nd,3rdeven lowerorder transfer structures were formed. They could be divided by "master faults profiles styles+plane styles+internal styles " into more than20subclassess, such as synthetic-overlapped-collateral transfer structure. The transfer structure owned the type of the "successional","successional-reconstructive","consuming" and "composite" former faults as a result of theformer Mesozoic fault system provided the advantage area.Under the control of extension,strike slip-extension and diapir,et al, various structures styles of transfer sturcture wereformed.The Cenozoic transfer structures in Jiyang Depression experienced the prscess of"original deformation (Ek) complex fragmentation (Es4) extensional fragmentation(Es3-Es2) retrogradation(Es1) reactivation (the end of Ed) die-away (N-Q)", which was different from the typical transfer structure in rift basin. The transfer structures chieflyaccommodated the extension conservation of the whole Jiyang Depression, and secondly thevertical divergence resulted from the nonhomogeneity extension. The transfer structuresbegan in different time, and the transfer degree varied in different areas. They developedearliest and strongest in Dongying Sag.The source rock distribution and maturity, glutenite and regional reservoir beds werecontrolled by the transfer structures, where structural and structural-lithologic reservoirs weremainly formed. Antitropic transfer structures owned the best hydrocarbon geologic settingsfor the double source feed, secondly was the synthetic type. The synthetic developednear-source reservoir model. The activity periods and strength and their match to the keyreservoir elements dominates the differences of hydrocarbon richness in in transfer structures.