| On the basis of plentiful geological data, cores, log data and high-resolution 3D seismic data, the theories of tectostratigraphy, sequence stratigraphy, oil and gas geology, and depositional system analysis were used synthetically. Through studying the tectonic controls on deposition, sequence and hydrocarbon accumulation, the fault system and their activities in the work area were researched; the sequence stratigraphic framework was built; the type of depositional system and its evolutionary rule of Dongying Formation in Nanpu Sag were analyzed systematically; the characteristics of the sequence structures were studied; the development patterns of sequence, deposition and oil and gas accumulation models controlled by faults activity were summed up; the point of view of integrative researching thought, structure - sequence - deposition - accumulation, was finally achieved; the exploratory beneficial target area of Dongying Formation in Nanpu Sag were pointed out.The paper is composed of the following parts:The first chapter was made up of by the aim and significance of this research. The research actualities of tectostratigraphy, continental sequence stratigraphy and petroleum geology home and abroad were summarized, combined with structure-sequence and structure-deposition analysis, the point of view of integrative researching structure - sequence - deposition - accumulation was achieved. The feasibility and important meaning of the research on the tectonic sequence stratigraphy in Nanpu Sag were proved. As a whole, the study of fault system features and their activities were based on the study of fault controls on sequence structures, deposition and oil and gas accumulation; while the research of sequence stratigraphy is the prerequisite of the analysis of depositional system, identifying the sequence boundaries and building the high precision sequence stratigraphic framework played an important role in this thesis, comparing the different sequence and depositional development, studying the relations between fault activities and deposition-sequence, researching the episodic trunk fault activities and its response to oil and gas accumulation were the final aim. The method of "point-line-surface-body-time" in sequence stratigraphy and the research means of "faulted activity-sequence-deposition-oil and gas accumulation" in faulted basin were combined in this paper.The second chapter introduces the basic geological settings of Nanpu Sag. Nanpu Sag, a meso-cenozoic basin, is located in northern Huanghua Depression of Bohaiwan Basin. It is the kind of sag that is small but rich in hydrocarbon in Bohaiwan Basin. Nanpu Sag is adjacent to Baigezhuang Uplift and Matouying Uplift with Baigezhuang basin-controlling fault as the boundary in the northeast; it is near to Xi'nanzhuang and Wanglaozhuang Uplift with Xi'nanzhuang basin-controlling fault in the northwest; and its northern gentle slope overlapped to the Shaleitian Uplift. The whole tectonic pattern of the sag is of NNE, and about 1932km2. Nanpu Sag had undergone 4 stages of tectonic movement in Paleogene. The sequence of Dongying Formation is corresponding to the last stage of the four. It was in the transition period from faulted subsidence to depression, and with developed reservoirs. Therefore, it is of significant exploration meaning.The third chapter analyzes the tectonic features of Nanpu Sag. Based on the recognition of Nanpu Sag as a typical half-graben like rift lake basin, faulted in the north and overlapped in the south, the sag is divided into four parts, which are, northern uplift zone, northern fault-controlling steep zone (downthrown sides of Xi'nanzhuang fault and Baigezhuang fault), central anticline tectonic belt (Nanpu-1, Nanpu-2, Nanpu-3, Nanpu-4 tectonic belts), and southern slope zone. The classification and activity studies have been done on the main faults of Nanpu Sag. The faults within the sag can be divided into 3 levels. Xi'nanzhuang fault and Baigezhuang fault, the sag-controlling faults, are the first grade faults; Gao-Liu fault, Nanpu-1 fault, Nanpu-2 fault, Nanpu-3 fault, Nanpu-4 fault etc, are subsag-controlling fault; the adjusting faults contemporaneous with the main faults and faults formed by the Neotectonic movement are the third grade faults. In addition, from the fault activity study on the main faults of Xi'nanzhaung fault, Baigezhuang fault, and Gao-Liu fault, it can be concluded that Xi'nanzhuang fault is of obvious segmentation, and can be divided into 3 parts, among which the east part developed the earliest and controlled the subsidence center of the sag together with Baigezhuang fault; the middle and the west part were of intense activity, and formed Nanpu-5 rolling anticline tectonic belt, and formed Laoyemiao transverse anticline. Ed1 period is the forming period of Laoyemiao transverse anticline, which is closely related to the Edl intense activity of Gao-Liu fault split the eastern part of Xi'nanzhuang fault into two, leading to the form of the uplift by the middle and the eastern rapid subsidence zones. Baigezhuang fault has no obvious segmentation, which showed two different subsidence features in the south and the north until the development of Gao-Liu fault; combining with the activity study on Xi'nanzhuang and Baigezhuang fault and the analysis of related geological features, it determines that the formation mechanism of Nanpu Sag takes the extension activity of Xi'nanzhuang fault the dominant part and sinistral strike-slip adjusting of Baigezhuang fault as subsidiary.The fourth chapter mainly studies on the controlling of tectonism on sequence stratigraphic framework. First, build the Paleogene sequence stratigraphic framework of the whole research area, and identify and trace the maximum flooding surface of Dongying Formation. Combining with seismic and drilling sequence, 12 main isochronic boundaries have been identified in the filling sedimentation of the research section, with 2 first-order sequence sets boundaries, 3 second-order sequence sets boundaries, 3 third-order sequence boundaries, 4 maximum flooding surfaces. (1) 2 identified first-order sequence sets boundaries: bottom boundaries of Es35 and Ng; (2) 3 identified second-order sequence sets boundaries: bottom boundaries of Es33, Es1, and Ed3; (3) 3 identified third-order sequence boundaries: (4) 4 identified maximum flooding surfaces within third-order sequence of Dongying Formation: Ed3xmfs, Ed3smfs, Ed2mfs, Ed1mfs. Based on this identification, the sequence of Dongying Formation can be divided into 3 different kinds of sequence stratigraphic frameworks, which are formed by the differential activities of sag-controlling faults and second-order faults within the sag. They have different control effects on sequence formation and filling: (1) the eastern sequence stratigraphic framework, mainly include Gao-Liu tectonic belt and Nanpu-4 tectonic belt. The whole framework was under the control of the structural styles of fault terrace formed by Xi'nanzhuang or Baigezhuang fault and Gao-Liu fault. The most remarkable feature is that because of the intense activity of Gao-Liu fault in Dongying Formation period, the uplifted side of Gao-Liu fault went upwards intensely, thus formed an isolated lake basin in Gao-Liu area and deposited and filled separately. The source of all of the eastern area came from the lateral Baigezhuang fault. (2) The middle sequence stratigraphic framework styles, mainly includes Laoyemiao tectonic belt, Linque sub-sag, and Nanpu-2 tectonic belt. The source mainly came from the south and north. In Dongying Formation period, fan delta was well developed in the north, and braided delta was also of large scale in the south, extending all the way to the Nanpu-2 tectonic belt. (3) The eastern sequence stratigraphic framework styles, mainly includes Nanpu-5 tectonic belt and Nanpu-2 tectonic belt. There were large amounts of reverse adjusting faults developed in Nanpu-5 tectonic belt. The source mainly came from the western slope zone as a lateral supply, and the south provenance extended all the way to Nanpu-1 tectonic belt. By comprehensive analysis of the sequence stratigraphic structure of Dongying Formation in Nanpu Sag, we build the sequence structural style of Dongying Formation in Nanpu Sag. It is believed that the sequence stratigraphic formation of Nanpu Sag was mainly under the control of tectonic slope-break zone. In the sag, 3 kinds of tectonic slope-break zone were developed, such as fault break zone, hinge zone, and fault bend zone.â‘ According to the location of faulted slope break belts distributed in Nanpu Sag, faulted slope break belts can be classified into steep faulted slope break belts and gentle faulted slope break belts. The former are the northern border of Nanpu Sag, they are Xi'nanzhuang fault and Baigezhuang fault, as well as the development of Dongying Formation sequence in the latter half under the control of Gao-Liu fault; the latter mainly in the southern slope of Nanpu Sag, are gentle faulted slope break belts. On the basis of the differences of faults complex style which controls the development of slope break belts, steep faulted slope break belts can be classified into single-step-type faulted slope break belts and multiple-steps-type faulted slope break belts. Single-step-type faulted slope break belts mainly refer to the position under the control of Gao-Liu fault developed in the middle and late Dongying Formation sequence, or the position of Xi'nanzhuang fault and Baigezhuang fault where haven't developed adjusting fault; Multiple-steps-type faulted slope break belts refer to the parts under the control of the faults which control the deposition of the whole Nanpu Sag and endoadaptation faults(e.g. Laoyemiao structural zone). ?Bucking Slope break belts are the parts where the deposition slope have significant changes in its slope gradient because of the sliding motion along with the shovel like normal faults which control the deposition of half-graben basin leading to bucking transformation of upper wall (gentle slope belt), using in describing control mode of dustpan fault depression on basin level. While the deformation of fault bend belts is in short distance, when the shovel like normal faults are activated, intensive deformation of deformational position of the hinge result in fracture consequently fault, reflecting on the differences in landform. Nanpu fault V developed in the western part in thrown wall of Xi'nanzhuang fault, considering as a rolling anticline on a whole. Because of intensive activity of western part of Xi'nanzhuang fault and the limitation of Nanpu fault I, sequentially result in the development of faulted-bend-type slope break belts. There are two positions of accommodation Space increased, both are formed because of this kind of slope break belts, one is under the control of Xi'nanzhuang fault, another is under the control of adjusting fault viz. the thrown wall of Nanpu fault V. (3)In the early of chasmic stage of Dongying Formation in Nanpu Sag (namely in developmental phase of Ed3x sequence), because of the intensive warped effect of the uplifted wall of Gao-Liu fault, hinge-type structural slope break belts are formed in Gao-Liu area. In the developmental phase of Ed3s sequence, under the affection of the structural slope break belts, Gao-Liu area become a insulated lake basin, and the slope break belts become a typical hinge-type structural slope break belts. Especially, the scope of exposure area is smaller, provenance offered by denudation process is feeble. As a insulated lake basin, lacking of supply of water, as while as large evaporation, this insulated lake basin was filled rapidly in a short time relatively. Till the developmental phase of Ed2 sequence, the uplifted wall of Gao-Liu fault has already filled basically, Gao-Liu fault become one of the faults which controlled the border of Nanpu Sag of Dongying Formation in this period.The fifth chapter is mainly about tectonic control to sedimentary system of every third-order sequences internal in Dongying Formation. Firstly, the cores observation and drilling lithology logging curve data were used and then connected to the analysis of seismic faces, it could be sure that clastic sedimentary system ,such as fan delta system-slump turbidities fan system, braided delta system and river delta, and so on, were mainly developed in Nanpu Sag. Its fan delta system could be branched out into (normal) fan delta system and nearshore subaquences fan system. Then through researching fault piecewise activity, analyzing rocks and mineral based on cores, logging data, compiled of sand body percentage content maps, thickness maps and seismic attribute analysis, five main source directions are confirmed in Nanpu Sag. They are respectively Jiannan source coming from west, Heiyanzi source and Luochaowan source coming from north, Matouying salient source coming from east, Shaleitian salient source coming from south. They all keeps inherited developing during different periods, sources of Dongying Formation keeps unchanged in each stage. Nanpu-5 tectonic belt, Laoyemiao tectonic belt and Gao-Liu tectonic belt, they are main entrances of sandbody distributed systems and are also accumulated in Nanpu Sag. On the basis of all of these, each third-order sequence sedimentary system of Dongying Formation is built, and vertical evolution rules are analyzed: the development of all the four third-order sequences sedimentary system are controlled by episodic tectonic movement, rifting episodic activity changed from strong to weak corresponds to processes of the development of fan delta and braided delta of Dongying Formation pushing into the sag centre while the range of lake atrophy continuously. The control effect of tectonics to sandbody is showed as fracture profile combination style control to sandbody and fracture plane combination style control to sandbody: According to characteristics of boundary faults, internal structures, planar distribution, structural situation, development evolution stage etc. features. The slope break types of Nanpu Sag are divided into four types of fracture profile combination styles: palisade type, ramp type, co-rotating fault terrace type, reversed fault terrace type, the distribution and accumulation of sandbody are controlled. It can be divided into four types of fracture plane combination styles to control the distribution of sand distributed system: accommodation zone, transverse anticlines, broom fracture combination and comb fracture combination.Chapter Six is the last part of this thesis, the controlling of fault to the formation of the oil and gas reservoir in Dongying Formation is studied. Actually almost all of key elements of petroleum system in Nanpu Sag are controlled by faults and their activities. Firstly, source-reservoir-cap rocks assemblages are determined by episodic tectonic movements controlled. Secondly, the distribution of the subsidence centers are controlled by activity of trunk faults. Thirdly, the formation and evolution of traps are also controlled by faults activity controlled. Fourthly, hydrocarbon migration pathways are controlled faults activity. At last, the migration ways of oil and gas are controlled by it. On the base of all of these, the hydrocarbon reservoir models of Laoyemiao, Nanpu-2, Nanpu-4 tectonic belts are analyzed. Then, the favorable zones for gas and oil in Dongying Formation are predicted, it is pointed out that Nanpu-2 and Nanpu-3 tectonic belts could be looked as the key of oil and gas exploration recently for its reliable bi-direction oil resource. While micro-amplitude structures which were formed by the neotectonic movement and located in the thrown side of Baigezhuang fault could be taken the new exploration breakthrough in this area.Innovations of the thesis are as follows:1. According to analyzing on activity of trunk faults such as Xi'nanzhuang fault and Baigezhuang fault, the characters of the segmented activity of Xi'nanzhuang fault and its controlling to sources system and sand body dispersion system are researched. On the base of this, forming mechanism of Laoyemiao transverse anticline and Nanpu-5 tectonic zone are sured.2. On the base of establishing high-accuracy stratigraphic sequence, typical sequence forming styles of Dongying Formation of Nanpu Sag was analyzed and they could be divided into three tectonic slope breaks: fault ramp zone, joint terminal zone and broken-bending zone. Specially through analyzing on activity of Gao-Liu fault and subtly interpretation of 3-order sequences, it was put forward that Gao-Liu area became a isolated lake basin during some period because the poured out effects of Gao-Liu fault in the early period of Dongying formation.3. Taking system tracts as basic units, the depositional system of Dongying sag of Nanpu Sag is studied. It is provided that the source entrances in Xi'nanzhuang fault is inherited during the different periods for Xi'nanzhuang fault is a extensive fault. While Baigezhuang fault needed to adjust the Xi'nanzhuang fault's displacement through sinistral slip activity.
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