| The Paleogene Kongdian fomation is the earlist strata in Huanghua depression inCenozoic, the Kongdian fomation records the initial process of the Cenozoic basin.This paper undered the guidance of sedimentology, sequence stratigraphy, structuralgeology and sedimentary basin dynamics theorise, analyzed the drilling and seismicdata in Huanghua Depression and its surrounding area, gained the knowledge ofresidual strata spatial distribution characteristics of Huanghua depression Kongdianformation, and the structural features in this area, combined with sedimentarycharacteristics obtained from cores, well logging and seismic data, identified the faultstructural activity characteristics of Huanghua Depression during the deposition ofKongdian, and the differences of evolution between the north and south of basin. Onthis basis, we try to analysis the Paleogene Evolution Process ofStructure-sedimentary in Huanghua Depression, and acquired the knowledge aboutthe deposition pattern of Huanghua Depression, basin tectonic evolution rule anddynamic mechanism in the initial stage of basin in Cenozoic. These knowledges willbe of great significance to the mineral resources exploration and active tectonicdynamic mechanism in this area. The thesis mainly made the followingunderstanding:1. On the basis of identifying the angular unconformities in the top and bottomboundary of Kongdian formation, the unconformities in Kongdian formation, thesedimentary discontinuity, the first flood surface, the maximum flood surface inHuanghua Depression, we could divide the Kongdian formation into one second-ordersequence, five third-order sequences and fifteen system tracts.2. According to analyzing the residual basin structure of the HuanghuaDepression, the residual basin could be divided into three categories: Double-breakstyle asymmetric graben structure (Ⅰ1)，Double-break style " with a Salient betweentwo depression" asymmetric graben and horst structure (Ⅰ2) and Single-break style "half graben " rift structures (Ⅱ1).3. The main faults such as Cangdong fault、Xu Xi fault、Kong Dong fault、KongXi fault in Huanghua Depression began extensionalal movement during the depositionperiod of SQ5. The Cangdong fault and Xuxi fault had stronger extensionalalmovement, and were controlled-basin boundary faults.4. According to analyzing the balanced cross-section, we could get theextensional amount and the extensional ratio of different position in the basin duringthe deposition period of SQ5, the main part of Cangdong depression have the mostintense stretch, the extensional amount is about4km, the extensional ratio is about 20%, while the extensional amount of Nanpi depression was relatively weak.5. According to analyzing the balanced cross-section and fault activity, it is clearthat the uplifting Kongdian Salient begin to form during the deposition period of SQ5,and the extensional movement, strike-slip movement of Cangdong and Xuxi faultsplayed a crucial effect in the formation process.6. The prototype basin is divided into two types or stages in the deposition periodof Kongdian Formation. The basin was depression basin in the early stage（thedeposition period of SQ1-SQ4） and rift basin in the late stage（the deposition periodof SQ5）, which suggestions that Huanghua depression experienced the transformationprocess from depression period to rift period. The extensionalal movemen（trift）in thedeposition period of SQ5controlled the formation of basin accommodation space andthe steep slope of basin margin. In addition，the right lateral strike slip of the faultsplay a important role in the formation and evolution of the basin during the depositionperiod of SQ5，mainly reflecting in the formation of basin secondary faults，small lowsalient（such as Shenvsi fault-nose）and Kongdian salient.7. The depositional systems filled in the depression basin have the followingcharacteristics：①there is no obvious north-south division about the distribution ofstrata, sequence development, the type and distribution of the depositional systems.②the characteristics of the spatial distribution of depositional systems are short axisalluvial fans and fan deltas develop in the east and west of basin margin. Thecharacteristics of the spatial distribution of depositional systems are long axis braidedriver deltas and alluvial fans develop in the north and south of basin margin. Thesediments’ size of this period is relative smaller.③the tectonic activity is weak andthe ancient typography elevation difference is not very large in the period, whichleaded to the relatively distant provenance and the relatively small sediment grainsize.8. The depositional systems filled in rift basin have the following characteristics:①due to the different intensity of activity in different locations of faults, theformation distribution, the sequence development, the type and distribution ofdepositional systems of this period is very different between in north and southpartition of basin.②the characteristic of the spatial distribution of depositionalsystems are short axis alluvial fans and fan deltas develop in the east and west ofbasin margin. The characteristic of the spatial distribution of depositional systems arelong axis braided river deltas and alluvial fans develop in the north and south of basinmargin.③the ancient typography elevation difference caused by the extensionalmovement of basin-controlling fault is great, resulting in the closer provenance of thisperiod, relatively larger sediment grain size and poor sorting.9. Huanghua Depression was intro-craton block-faulted basins（Rift basin）in the deposition period of the Paleogene Kongdian formation. The basin is the result of theshallow effect due to the destruction of the North China craton. We initially establishthe coupling relationship between the deep process and the structure-sedimentaryevolution of basin，and divide the period into4stages：①Arch stage（beforedeposition of Kongdian formation）；②Depression stage（the deposition period ofSQ1-SQ4）；③Rifting stage（the early deposition period of SQ5）；④Rift_filling stage（the late deposition period of SQ5）... |
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