古地理学报2016，Vol.18Issue(4)：631-642,12.DOI:10.7605/gdlxb.2016.04.047
鄂尔多斯盆地南缘奥陶系平凉组等深流沉积
Contourites of the Ordovician Pingliang Formation in southern margin of Ordos Basin
摘要
Abstract
The contourites,gravity flow deposits and deep water autochthonous deposits,consisting of limestone,mudstone with sandstone with radiolarian chert and volcanic tuff interbeds,were developed in the Ordovician Pingliang Formation in the southern margin of Ordos Basin.Contourites were divided into calciruditic contourites,calcarenitic contourites,calcisiltitic contourites,calcilutitic contourites and silt-sandy contourites.Ripples and bioturbation were well shaped on top of calcisiltitic contourites.The ripples, with wave length 1 -5cm and wave height 0.2-0.5cm,were asymmetric and showed migration direction obviously.The complete and incomplete sedimentary sequences were composed of superimposed calcarenit-ic contouritse,calcisiltitic contourites and calcilutitic contourites,and displayed upward fine-coarse-fine trend with thickness several millimeters to centimeters.The sequences consisted of not only superimposed multilayer,but also single layer,or appeared between two adjacent muddy layers or stylolites;and the thickness of the upward-coarsening sequences and the upward-fining ones were asymmetrical.Contour cur-rent moved from the east to the west with path subparallel to the slope.The deep water autochthonous de-posits and gravity flow deposits were developed in the lower part of the Lower Pingliang Formation;by con-trast,the deep water autochthonous deposits and contourites were favored in the upper part.The contou-rites were mainly influenced by tectonic movements,relative sea-level rise,current energy,palaeotopog-raphy and motion path.关键词
等深流/等深流沉积/等深积岩/鄂尔多斯盆地/平凉组Key words
contour current/contour current deposit/contourite/Ordos Basin/Pingliang Formation分类
天文与地球科学引用本文复制引用
李华,何幼斌,黄伟,刘朱睿鸷,张锦..鄂尔多斯盆地南缘奥陶系平凉组等深流沉积[J].古地理学报,2016,18(4):631-642,12.基金项目
国家自然科学基金项目（批准号41472096、41502101）、湖北省创新群体基金项目（编号2015CFA024）及长江青年基金项目（批准号2015cqn26）联合资助。［Co-funded by the National Nature Science Foundation of China （No.41472096，41502101），Group innovation fund of Hubei （No.2015CFA024） and the Yangtze Youth Fund （No．2015cqn26）］ （）
