摘要
依据对钻井、测井和地震资料,认为东营凹陷北部坨71块古近系沙河街组三段下部为近源浊积成因的砂砾岩体.岩性为暗色泥岩夹砂砾岩、砂岩和粉砂岩,颗粒粗,分选中到差,成分成熟度低.递变层理、叠覆递变层理、块状层理、滑塌、撕裂屑、直立砾、漂砾、重荷等沉积构造广泛发育.自然电位和电阻率曲线由高幅箱形到低幅齿化,与不同岩性和沉积相具有良好的对应关系.在地震剖面上近源浊积扇外形呈丘状,内部为杂乱反射.根据岩性、电性和沉积序列组合特征,在研究区识别出内扇、中扇和外扇.在上述基础上,归纳了近源浊积扇标志,为识别该类成因扇体提供借鉴.
It is held that the glutenite occurring in the lower part of the third member of the Paleogene Sha-hejie Formation originates from proximal turbidity according to the data of drilling cores, well-logging and seism in Tuo-71 block of Dongying Sag. It consists of dark mud shale with glutenite, sandstone and siltstone. The grain of the sediment is coarse, its sorting is poor to moderate, and its compositional maturity is low. This sequence is interpreted as proximal turbidity fan, evidenced by the presences of the sedimentary structures, such as graded bedding, superposition graded bedding , massive bedding, and of the depositional structures including slumps,rip-up cuttings, boulder and load cuttings. The spontaneous potential and resistance: curve change from box-like shape with high amplitude to tooth shape with low amplitude, which are closely related to different lithology and sedimentary facies. The proximal turbidity fan deposits appear dune-shaped in the seismic profiles. The seismic reflection is disordered. According to lithology, electrical behavior and sedimentary sequences, the proximal turbidity fan can be divided into three sub-facies, including inner fan, middle fan and outer fan. At last, the characters of the proximal turbidity are summarized up, which can provide a reference for identifying this kind of proximal turbidity fans.
出处
《西安石油大学学报（自然科学版）》
CAS
2005年第4期39-42,共4页
Journal of Xi’an Shiyou University（Natural Science Edition）
关键词
东营凹陷
沙河街组
近源浊积扇
砂砾岩体
沉积特征
Dongying Sag
Shahejie Formation
proximal turbidity fan
glutenite body
depositional feature
