Tectonostratigraphic units and stratigraphic sequences of the nonmarine Songliao basin, northeast China

• Published in: Basin Research
• Main Authors: Zhi‐qiang, Feng, Cheng‐zao, Jia, Xi‐nong, Xie, Shun, Zhang, Zi‐hui, Feng, Cross, Timothy A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2010
• Subjects: Okhotsk; Pacific; okhotsk sea
• Online Access: http://dx.doi.org/10.1111/j.1365-2117.2009.00445.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-2117.2009.00445.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2117.2009.00445.x

ABSTRACT Through tectonostratigraphic analysis of the nonmarine, intracontinental Songliao basin in northeast China, four episodes of deformation are recognized: mantle upwelling, rift, postrift thermal subsidence and structural inversion. The episodes are related to regional geodynamics and plate motions. Each episode is associated with a specific stratigraphic signature. The first period of deformation occurred during the Middle and Late Jurassic when asthenospheric upwelling heated, thinned and stretched the lithosphere. These events may have been caused by the narrowing of the Okhotsk Sea through subduction. This deformation is characterized by doming, extension, widespread volcanism and intrusion, and erosion. Volcanics interfinger with alluvial fan and alluvial plain facies systems tracts. The second rifting episode began in the latest Jurassic and continued into the Early Cretaceous. It resulted in the formation of a large number of isolated, NNE‐trending fault blocks of ‘basin‐and‐range’ style. Rifting may have been caused by the formation and subduction of the Izanagi and Pacific Plates. Coal‐bearing fluvial, floodplain, lacustrine and fan‐delta strata and widespread volcanic rocks filled the fault‐block basins. Volcanic strata hundreds to several thousand meters thick in the Huoshiling and Yingcheng Formations record multiple intrusive events during the rifting stage in the basin. These events were concurrent with episodes of intrusion and volcanic eruption in northeast China. The third phase of regional postrift deformation and subsidence, which began with the Lower Cretaceous Denglouku Formation, was caused by lithospheric cooling and extension, modulated by multiple compressional events. Subsidence in the Songliao basin permitted accumulation of thick postrift deposits, in contrast with other Cretaceous basins in Mongolia and northeast Asia. Three compressional episodes, which episodically interrupted the long‐term cooling subsidence, originated from development of the Okhotsk suture and subduction ...