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The onset of uplifting of the Mid‐upper Yangtze area is constrained by the combination of analysis of apatite fission track (AFT) age and modeling of fission track length distribution. The results show that the general trend of onset of uplifting is characterized by decreasing westward in geological time for the different tectonic units in the Mid‐upper Yangtze area. Two episodes of uplifting in Jianghan basin occurred within 157~97 Ma and 10~0 Ma; Xiang'exi‐Wuling area experienced an uplifting in 137~0 Ma; E'xi Yudong area, Chuandong folds, Qianzhong Hights and Dian‐Qian‐Gui areas in 97~0 Ma; Northern Sichuan basin and Chuanzhong areas in 56~0 Ma; and Chuanxi depression and Dianxi region in 23~0 Ma. The major faults of Qiyueshan, Huanyinshan and Longquanshan controlled the boundaries of the onsets of uplifting. The onsets of uplifting for the areas east of Qiyueshan fault, in between Qiyueshan and Huayinshan faults, in between Huayinshan and Longquanshan faults, west of Longquanshan fault are late Jurassic‐early Cretaceous (J3‐K1), late Cretaceous (K2), Paleogene (E) and Neogene (N), respectively.

As the most frontiers in petroleum geology, the study of dissolution-based rock formation in deep carbonate reservoirs provides insight into pore development mechanism of petroleum reservoir space, while predicting reservoir distribution in deep-ultradeep layers. In this study, we conducted dissolution-precipitation experiments simulating surface to deep burial environments (open and semiopen systems). The effects of temperature, pressure, and dissolved ions on carbonate dissolution-precipitation were investigated under high temperature and pressure (∼200 ∘ C; ∼70 Mpa) with a series of petrographic and geochemical analytical methods. The results showed that the window-shape dissolution curve appeared in 75∼150 ∘ C in the open system and 120∼175 ∘ C in the semiopen system. Furthermore, the dissolution weight loss of carbonate rocks in the open system was higher than that of semiopen system, making it more favorable for gaining porosity. The type of fluid and rock largely determines the reservoir quality. In the open system, the dissolution weight loss of calcite was higher than that of dolomite with 0.3% CO 2 as the reaction fluid. In the semiopen system, the weight loss from dolomitic limestone prevailed with 0.3% CO 2 as the reaction fluid. Our study could provide theoretical basis for the prediction of high quality carbonate reservoirs in deep and ultradeep layers.

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