| With the development of petroleum industry, sequence stratigraphy theories go fast from conventional sequence stratigraphy that is focus on sequence research of basin-type and tectonic oil-gas pool to high-resolution sequence stratigraphy that is applicable to research on subtle traps and reservoir-scale sequence. The sequence framework at the scales of four or five unit is more consistent to the practice of subtle trap exploration and reservoir development than the scale of two or three unit of the conventional sequence. High-Resolution sequence stratigraphic technology is one of most effective approaches these days which are being used extensively in the research of petroleum exploration and development.After the phase of 30 years research on tectonic oil-gas pools, the focus of the exploration in Huimin Sag is gradually on to subtle traps and oil-gas pools. However, Huimin Sag is a region where few sequence research is done and exploration of subtle trap has just begun. Approaches that deal with chronostratigraphic framework ., distribution of supplying sources and subtle targets are strongly needed. High-resolution sequence stratigraphic theory is the first choice. Application of high-resolution sequence stratigraphy in subtle trap exploration will result in forming some approaches and technologies for subtle oil-gas pool exploration and providing basis for making decisions on subtle explorations for a period since then.Based on well logs, three -dimension seismic profiles, cores and other basic data, author recognized the sequence horizons of high-scale by the changes of A/S ratio, and established high-resolution chronostratigraphic framework using multi-term base-level cycles of high-resolution sequence stratigraphy ,combining sequence theory with sedimentology. The depositional system characters and distribution were outlined and the prospective areas for stratigraphic traps were defined: Jishan and Jiangjiadian. Then the research on characters, evolution and distribution of micro-sedimentary facies were finely studied. The favourable subtle strap regions were recognized and prospective subtle oil-gas pools as regard the characters of reservoir-quality , seals and migration pathways were defined and evaluated.After the research on S3 to the lower part of S2 of Paleogenene, 10 horizons including 6 turnaround surfaces and 4 flooding surfaces were defined, and 1 long-term and 5 intermediate-term base-level cycles could be identified, and then the chronostratigraphic framework of the Sag was built. There are 5 depositional systems in the region. They are: Panhe and Jishan delta systems coming from Chengning heave near the northwest border of the region, Shuangfen delta located in southwest part of the region coming from Luxi dome, Qudi fan-delta located in the southeast of the studying area and the sub-fan near fault or fan-delta of the southern part of the region. According to paleo-geomorphology and depositional systems analysis, three kinds of forming models of subtle traps were built. They are fan-delta front-slope-sliding turbidity subtle traps N sub -fan near fault -stepping faults-turbidity subtle traps and fan-delta-furrow-sub-fan -sliding turbidity subtle traps.This paper shows that favourable oil-pool-forming condition can be found in Linnan sag. There are three main kinds of subtle oil-gas-pools: up-acclivity pinch-out sandstone, lenticle and fault-stratigraphy subtle oil-gas pools. The most favourable sequences for subtle traps are cycle 3 and cycle 4,and the most favourable oil and gas-pool forming regions are Jishan sandstone, fan-delta sandstone of south part ofLinnan Sag,sliding turbidity sandstone of the slope part of Shuangfen delta front and turbidity and sub-fan near fault of Jiangjia Dian .The successes of the exploration of Xia 94 demonstrates that Linnan Sag is a big and potential subtle trap oil-gas-bearing zone, accelerates the collective research on the exploration technology leading by sequence stratigraphy and other subtle oil-gas pool theories ,and provides re...
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