A study of sequence stratigraphy of the Early Cretaceous coal-bearing series in the southeastern Songliao Basin, NE China

Abstract

The Early Cretaceous is an important coal accumulation period in China. Abundant coal resources were formed in the southeastern margin of Songliao Basin. Sequence stratigraphy and coal accumulation of the Early Cretaceous in the southeastern margin of Songliao Basin have been studied on the basis of extensive outcrop and borehole data. Based on regional unconformity, basal erosional surfaces of incised valley fills, and abrupt depositional facies-reversal surface, six sequence boundaries have been identified, which subdivide the Early Cretaceous coal-bearing series into 5 third-order sequences. Sequence I corresponds to Huoshiling Formation, sequences II and III correspond to member I and member II of Shahezi Formation. Sequences IV and V correspond to member I and member II of Yingcheng Formation. Sequence I developed at the initial subsiding stage, sequence II and III developed during the stable subsiding stage, while sequence IV and V developed during the basin shrinkage stage. The major coal seams were developed in the sequence II and III, which ensured the relative balance between the increase rate of the accommodation space and the rate of peat accumulation for a longer period, thus forming a thick coal seam.

Characteristics and evolution of inertinite abundance and atmospheric pO2 during China’s coal-forming periods

“…The coal-bearing strata were mainly formed in alluvial fans, fan deltas, lakeside deltas, and lacustrine environments. The coal-rich belts were mainly located on the sides of main faults near basin margins, with their distribution directions consistent with basin trends (Cai et al 2011;Shao et al 2013).…”

Characteristics of Early Cretaceous wildfires in peat-forming environment, NE China

“…NE China includes Heilongjiang, Jilin and Liaoning Provinces and the eastern part of Inner Mongolia Autonomous Region with a vast area of roughly 1.6 million km 2 (Shao et al 2013). Tectonically, the region consists of Hailar Basin and Erlian Basin in the west, Songliao Basin in the center, and Sanjiang Basin in the east (Fig.…”

“…1 (Li 1988), formed mainly in continental environments. Lower Cretaceous successions are unconformably overlain by Upper Cretaceous sedimentary rocks, and unconformably underlain by the Upper Jurassic (Shao et al 2013).…”

Sequence palaeogeography, lacustrine basin evolution, and coal accumulation in the Lower Cretaceous Fuxin continental faulted basin, China

“…The Early Cretaceous was an important period for coal accumulation in China (Shao, Shao, et al, ; Li et al, ). Over the past decade, considerable attention has been paid to coal accumulation in continental faulted basins in northeastern China (Gao, Shao, & Li, ; Guo, Shao, Hilton, Wang, & Zhang, ; Shao, Shao, et al, ; Wang et al, ; Wang et al, ; Wang et al, ) including the Fuxin Basin in the western part of Liaoning Province.…”

“…The Early Cretaceous was an important period for coal accumulation in China (Shao, Shao, et al, ; Li et al, ). Over the past decade, considerable attention has been paid to coal accumulation in continental faulted basins in northeastern China (Gao, Shao, & Li, ; Guo, Shao, Hilton, Wang, & Zhang, ; Shao, Shao, et al, ; Wang et al, ; Wang et al, ; Wang et al, ) including the Fuxin Basin in the western part of Liaoning Province. As an important coal‐bearing basin, the sedimentary environment, palaeontology, tectonic evolution, and coal accumulation have been investigated in detail (Cai et al, ; Chen, ; Chen, Yang, & Zhou, ; Gao, He, Ma, & Yang, ; Guo, ; Li, ; Liu & Chen, ; Qiu, ; Shang, ; Wang, ; Wang, Liu, & Sun, ; Wang, Xiang, & Huang, ; Zhang & Zhang, ; Zhao, Wang, & Jiang, ; Zhu, Shen, Lu, & Yan, ).…”