Gravity flow and internal wave and internal tide deposits in Upper Miocene of SE area, Yinggehai Basin

Integrated with cores, micro-resistivity images and conventional logs, deposits in the 1st member of the Huangliu Formation of the Upper Miocene in the SY and SE areas in the Dongfang tectonic belt of the Yinggehai Basin were analyzed in detail. It was shown that a set of fine-grained deposits of submarine fan developed in the 1st member of the Huangliu Formation, and the deposits were reformed by internal wave and internal tide of deep-water tract current during gravity flow deposition process, forming 5 typical lithofacies: 1) fine-grained sandstone with bidirectional sand ripple; 2) laminated sand and shale with flaser, wavy and lenticular bedding; 3) fine-grained sandstone with double mud layers or mud stripe; 4) Massive and graded fine-grained sandstone; 5) fine sandstone with floating mud clasts or mud debris. The 1st member of the Huangliu Formation in the SE area was mainly gravity flow deposits and partially internal wave and internal tide deposits, and the 2 kinds of deposits coupled locally.