摘要
The only major breakthrough in the exploration of the Sinian of the Sichuan Basin has been the Weiyuan gas field. Taking the typical structures in the Sichuan Basin as examples, an apatite fission track simulation was applied to constrain the thermal evolutionary history of the source rocks in this study. Combined with trap formation and evolution, the formation, destruction, and accumulation history of the Sinian reservoirs were analyzed from a dynamic perspective. The Sinian reservoirs underwent several primary stages： the paleo-reservoir formation and destruction in the late Silurian, hydrocarbon recharge in the Permian-Triassic, the cracking of oil to gas and dissolved-gas in the late Triassic-Mid-Late Jurassic, and the exsolution and accumulation of dissolved-gas as a result of episodic uplift since the Late Cretaceous. The exsolution process of dissolved-gas is of great significance to the accumulation of natural gas. The formation of the Weiyuan gas field is also related to this process. The Sinian in the Sichuan Basin has a broad exploration prospect, and exploration targets focused on the Leshan-Longnüsi Paleo-uplift tectonic zone with weak influences on potential hydrocarbon reservoirs from the late tectonism and transformation.
The only major breakthrough in the exploration of the Sinian of the Sichuan Basin has been the Weiyuan gas field. Taking the typical structures in the Sichuan Basin as examples, an apatite fission track simulation was applied to constrain the thermal evolutionary history of the source rocks in this study. Combined with trap formation and evolution, the formation, destruction, and accumulation history of the Sinian reservoirs were analyzed from a dynamic perspective. The Sinian reservoirs underwent several primary stages： the paleo-reservoir formation and destruction in the late Silurian, hydrocarbon recharge in the Permian-Triassic, the cracking of oil to gas and dissolved-gas in the late Triassic-Mid-Late Jurassic, and the exsolution and accumulation of dissolved-gas as a result of episodic uplift since the Late Cretaceous. The exsolution process of dissolved-gas is of great significance to the accumulation of natural gas. The formation of the Weiyuan gas field is also related to this process. The Sinian in the Sichuan Basin has a broad exploration prospect, and exploration targets focused on the Leshan-Longnüsi Paleo-uplift tectonic zone with weak influences on potential hydrocarbon reservoirs from the late tectonism and transformation.
基金
funded by the National Key Basic Research Programs (973) "Deep hydrocarbon accumulation mechanism of China’s marine carbonate strata" (2005CB422106)
"The structure evolution in middle and upper Yangtze region and multi-period hydrocarbon accumulation in lower Paleozoic" (2012CB214805)
