大港滩海区埕北断阶带古近系层序界面的识别方法  

Identification method of sequence boundary for Eogene of Chengbei step-fault zone in Dagang offshore area

作　　者：曲希玉[1] 刘立[1] 刘娜[1] 吴文波[2] 

机构地区：[1]吉林大学地球科学学院,长春130026 [2]大港油田集团公司井下技术服务公司,天津大港300282

出　　处：《世界地质》2007年第4期484-491,共8页World Geology

基　　金：大港油田科技攻关项目(200312技984);大港油田第一采油厂项目(DGYT-2006-JS-J891)资助

摘　　要：通过对大港滩海区埕北断阶带层序地层的研究,将研究区古近系划分为3个三级层序,总结了5种识别层序界面的方法:①地震识别法;②钻井识别法;③测井识别法;④古生物组合识别法;⑤地球化学识别法。在研究区,方法①表现为区域性的上超和削截;方法②表现为岩性和泥岩颜色的突变;方法③表现为各种曲线和地层倾角的突变;方法④表现为古生物组合类型的变化;方法⑤表现为Fe2+/Mn2+值由下向上由逐渐增大,转为突然变小。其中方法①、③、④是层序界面的主要识别标志,方法②可作为参考标志,而方法⑤的应用效果较差。By research on the sequence strata in the studied area, the Eogene can be divided into three 3rdorder sequences, and five methods for identifying sequence boundary were introduced, including ①seismic method, ② drilling method, ③logging method, ④paleontological method, and ⑤ geochemistry method. The first method appears as onlap and truncation in regionality, the second as abrupt change in lithology and color of mudstone, the third as abrupt change in all curves and stratigraphic dips, the fourth as change in type of palaeobiocoenosis, and the fifth as the ratio of Fe^2＋ and Mn^2＋ increasing from bottom to top, then decreasing abruptly. Of which the methods 1, 3 and 4 are item key in identification of sequence boundary, the second can be witness marker, but the fifth is poor in application effect.

关 键 词：层序界面 识别方法 大港滩海区 

分 类 号：P534.6[天文地球—古生物学与地层学] P631[天文地球—地质学]