| This study uses 3D model construction software and the G1S tool, as well as a great deal of geological and geophysical data to establish a subsurface model for the Quanzhou basin. The main results of the thesis are summarized as below.1. The sequence stratigraphy method is used to set up the standard profile of the Quaternary stratum and the isochronous sequence-structure framework for the study area. Then the subsurface 3D sequence-structure framework beneath the urban area is obtained by layering subdivision of borehole data and 3D structural model construction. Based on these data, spatial distribution of faults in the cover layers of the basin, and their activity time and combination features can be analyzed. This is an effective method to acquire information of subsurface structure and faults beneath a urban area.2. According to the reference profile section of Quaternary stratum, synthesis column chart and equal-time sequence interfaces of the Quanzhou basin, and the chronostratigraphic classification result acquired during the study, 5 sequence formations and the age of each isochronous sequence interface are determined: the forming time of Longhai Formation is 125000 to 25000 a B.D; that of lower part of Dongshan Formation is 25000 to 15000 a; that of upper part of Dongshan Formation is 15000 to 10000a; that of lower part of Changle Formation is 10000 to 3000 a; and that of upper part of Changle Formation is 3000 to 0 a.3. The database including data from 300 boreholes and a 3D sequence-structure framework model of the Quanzhou basin by 3D software.4. The Qingyuanshan fault with a strike of northwest controls the northwest border of the Quanzhou basin and the faults in the blind area of the basin with the same strike as the Qingyuanshan fault doesn't extend into the city. The Kaiyuan Temple uplift is under the control of faults with northeast strike. The Jinjiang fault is formed in the blind area of the basin, and is considered to be the extention of the Sijiao fault towards the basin approaching to Fashi, southeast of the basin. The huger scale of the Wushishan fore-hill fault represents in almost all the layers in the sequence. The graben controlled by the Wushishan fault and the Jinjiang fault also affects any structural layer of the basin.5. The geometry of the Jinjiang fault zone is determined, and it is composed of several parallel faults with northwest strike and southwest dip. The Jinjiang fault zone and the Wushishan fault form the faulted Jinjiang valley graben. It is also proved that the Citong fault with northeast strike exists in the basin.6. The structural combination of northwest trending faults and structures in the Quanzhou basinis the Qingyuanshan horst, the Qingyuanshan fore-hill trough, the Shijiaoshan-Kaiyuan Temple-Fashi horst, the Jinjiang valley graben and the Wushishan horst. The assemblege of northeast faults and structures in the Quanzhou basin is the Shijiaoshan horst, the Xihu graben, the Kaiyuan Temple horst, the Citong graben, the Fashi horst, and the Jinjianghe graben. These horsts and grabens are recognized firstly by 3D modeling analysis of the thesis.7. The faults in the Quanzhou basin formed in Quaternary are dominated by normal faults in extensional environment. A series of grabens and horsts form extensional Quanzhou basin, which appeared as a faulted basin in the Longhai and Dongshan period and as a depression basin in the Changle period.
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