Did the eruption of the Tarim LIP control the formation of Paleozoic hydrocarbon reservoirs in the Tarim basin, China?

The Tarim basin not only is one of the main targets for hydrocarbon exploration in China, but also hosts the Early Permian LIP, thereby providing an ideal laboratory to investigate how the LIP eruptions interact with the petroleum system in the volcanic-affected basins. Six major second-order domes were identified in the first-order dome that involves the entire Tarim LIP, based on seismic probing and lithofacies and stratigraphic observations in boreholes and the stratigraphic sections. These second-order domes are characterized by abundant Permian basaltic dykes and volcanic craters, indicative of the origin from the LIP eruption. They also are the sites of the almost all Paleozoic oil and gas reservoirs in the Tarim basin. Dating on authigenic illites collected from 20 Silurian bituminous and oil-saturated sandstone samples in the Tarim basin, along with literature data, indicates that hydrocarbon charge and emplacement in the Paleozoic reservoirs prevalently occurred during 300-255 Ma, approximately concurrent with the eruption of the Tarim LIP lavas (300-262 Ma). Therefore, we propose that the LIP eruption not only created the second-order domes that provided space for the oil and gas charge but also triggered the rapid release of hydrocarbon through the volcanic vents, thereby controlling the formation of Paleozoic oil and gas fields in the Tarim basin. (c) 2021 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Automated summary

The Tarim basin in China is a main target for hydrocarbon exploration and hosts the Early Permian LIP. Six major second-order domes were identified in this area, characterized by Permian basaltic dykes and volcanic craters, where almost all Paleozoic oil and gas reservoirs are located. The eruption of the LIP is proposed to have created space for oil and gas charge and triggered the rapid release of hydrocarbons, controlling the formation of Paleozoic oil and gas fields.