This paper presents a quantitative analysis of Jurassic-Quaternary basement subsidence in the Delingha basin, a tensile basin and compressive mountain type diwa basin, and corrected for local sediment loading. Subside...This paper presents a quantitative analysis of Jurassic-Quaternary basement subsidence in the Delingha basin, a tensile basin and compressive mountain type diwa basin, and corrected for local sediment loading. Subsidence patterns have been investigated for the effects of erosion induced uplift by means of analytical estimation. The history of the Delingha basin has been divided into four stages: 204(?)~130 Ma (SⅠ ), 130~95 Ma (SⅡ ), 67~35 Ma (SⅢ ) and 35~0 Ma (SⅣ ), recording episodic tectonics and sedimentation respectively.展开更多
Since the late Hercynian episode the crust in Hainan has entered the post-platform activation or the diwa stage in which it has undergone a process from compressive (collision) orogeny and up1ifting during the late He...Since the late Hercynian episode the crust in Hainan has entered the post-platform activation or the diwa stage in which it has undergone a process from compressive (collision) orogeny and up1ifting during the late Hercynian-Indosinian movements to block-faulting type mountain- and basin-making during the Yanshanian-Himalayan movements. It has been shown through researches of igneous rocks that a post-platform orogenic belt being of a greatly thickened continental crust was once formed in the Hainan area during the late Hercynian-lndosinian cyc1e. The taphrogeny starting in the late Yanshanian episode was a product at the stage of late orogenic extension under conditions of the mountain root with a thickness of about 60 km retained. At 1ast, the lower lithospheric delamination and the crustal de-rooting of the orogen caused Hainan and its neighboring areas to transform from the continenta1 type crustobody to the continental-margin-spreading type crustobody.展开更多
文摘This paper presents a quantitative analysis of Jurassic-Quaternary basement subsidence in the Delingha basin, a tensile basin and compressive mountain type diwa basin, and corrected for local sediment loading. Subsidence patterns have been investigated for the effects of erosion induced uplift by means of analytical estimation. The history of the Delingha basin has been divided into four stages: 204(?)~130 Ma (SⅠ ), 130~95 Ma (SⅡ ), 67~35 Ma (SⅢ ) and 35~0 Ma (SⅣ ), recording episodic tectonics and sedimentation respectively.
文摘Since the late Hercynian episode the crust in Hainan has entered the post-platform activation or the diwa stage in which it has undergone a process from compressive (collision) orogeny and up1ifting during the late Hercynian-Indosinian movements to block-faulting type mountain- and basin-making during the Yanshanian-Himalayan movements. It has been shown through researches of igneous rocks that a post-platform orogenic belt being of a greatly thickened continental crust was once formed in the Hainan area during the late Hercynian-lndosinian cyc1e. The taphrogeny starting in the late Yanshanian episode was a product at the stage of late orogenic extension under conditions of the mountain root with a thickness of about 60 km retained. At 1ast, the lower lithospheric delamination and the crustal de-rooting of the orogen caused Hainan and its neighboring areas to transform from the continenta1 type crustobody to the continental-margin-spreading type crustobody.