Qingshan Gr
Type Locality and Naming
Jiaolai Basin. Tan Xichou erected the Qingshan bed in 1923. Du Benming et al. (1991) named it as the Qingshan Group. The type locality for the designation is in Qingshan of the Laiyang County, Shandong. The reference section is from Wawukuang to Xidoushan about 12 km southeast of the Laiyang City, Shandong. It is an upward succession of the Qugezhuang Fm or coeval Houkuang Fm, Bamudi Fm, Shiqianzhuang Fm and Fanggezhuang Fm.
Synonym: Qingshan Fm; the Xiwa Fm is a similar grouping of the Bamudi Fm, Tianjialou Fm (=Shiqianzhuang Fm ?) and Fanggezhuang Fm
Lithology and Thickness
The Qingshan Group is dominated by volcanic rocks, which is divided in ascending order into three members (now formations). First member is built up by gray green and purple gray sandstone with green gray silty mudstone and purple conglomerate and boulder conglomerate. Second member light gray and yellow green tuff, tuffaceous sandstone, andesite breccia, agglomerate and breccia, with the gravels being made up of andesite and small amounts of rhyolite. Third member basalt andesite, and andesite breccia interbedded with agglomerate, with andesitic conglomerate in the upper part. The formation is 935 m thick.
Relationships and Distribution
Lower contact
The base of the formation marked by gray brown gravel-bearing grit is distinguished from medium and coarse-grained sandstone of the underlying Laiyang Fm (Laiyang Gr) and is in disconformable contact with the latter.
Upper contact
The top marked by the appearance of red sandy mudstone lies unconformably under the overlying Wangsi Fm (Wangsi Gr).
Regional extent
The formation occurs in Mengyin, Pingyi, Laiwu, Zouping, Linxun, Yiyuan, and in Tancheng, Juxian and Anqiu of the Yimu river domain in west Shandong; Zhucheng, Jiaozhou, Jimo, Laixi and Laiyang of east Shandong where it covers a large area and is represented by intermediate and acid rocks. In west Shandong, it is dominated by moderately basic rocks occurring as a stripe. In Weifang and Tancheng between east and west Shandong, it is dominated by intermediate and slightly alkaline volcanic rocks, covering a small area. In the Zhujia Village of Laiyang, it lies unconformably on the Proterozoic metamorphosed rocks.
GeoJSON
Fossils
In Zhujiazhuang of Laiyang, it yields bivalves Nippononaia laiyangensis, N. zhujiazhuangensis, Nakamurania chingshanensis, N. elongata, N. subrotunda, Sphaerium yanbianensis; estherias Yanjiestheria sinensis, Orthestheriopsis sp.; ostracods Cypridea koskulensis; to the northwest of the Doushan Village, Reptilia Psittacosaurus sinensis, P. youngi; Chelonia Peishanemys latipous; in Zhujiazhuang and Huangxian, sporopollen grains such as the Cicatricosisporites-Classopollis-Asteropollis assemblage.
Age
Depositional setting
It is of volcanic facies.
Additional Information