鲁西隆起北侧博兴洼陷新生界碎屑重矿物记录及其对构造古地理环境的指示  

Characteristics of Mesozoic and Cenozoic heavy minerals in the Boxing Sag and their tectono-paleogeographic implications

作　　者：许承武[1] 李忠[1] 韩登林[1] 韩银学[1] 彭守涛[1] 刘嘉庆[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029

出　　处：《地质科学》2009年第1期257-267,共11页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金（批准号：40672083）资助.致谢 感谢河北省地质矿产局实验室李林庆高级工程师在样品前期处理方面给予了大量帮助,感谢两位审稿人对本文提出的宝贵意见.

摘　　要：对鲁西隆起北侧博兴洼陷新生界碎屑重矿物组份和稳定性组合的研究发现：古近纪孔店组沉积期、沙河街组四段沉积晚期和沙河街组二段沉积期金红石、电气石、锆石和白钛矿等稳定碎屑重矿物占优势，指示盆-山的构造古地理分异较弱；沙四段沉积早期、沙三段和沙一段沉积期绿帘石、榍石等不稳定碎屑重矿物占优势，表明构造古地理分异强烈。新近纪馆陶组稳定重矿物自下而上逐渐占据优势，表明该时期构造活动逐渐趋缓；明化镇组自下而上不稳定重矿物逐渐占优势，指示构造活动逐渐加强。根据砂岩中自生矿物赤（褐）铁矿的分析，认为其含量较高的孔店组、沙四段、沙一段沉积期气候干旱，而含量较低的沙四段沉积末期—沙二段沉积期气候湿润；新近纪里赤（褐）铁矿含量向上增大，可能指示气候干旱程度加剧。The paper studied characteristics of heavy minerals from drill cores in the Boxing Sag. According to the heavy mineral components and stability index, the Cenozoic in West Shandong area could be divided into nine periods with varied tectonic activities. The steady minerals, such as futile, tourmaline and zircon were in the ascendant at the sedimentary periods of the top part of 4^th Member and 2^nd Member, Shahejie Formation, which showed a tectonic active setting during the both periods. The unstable minerals such as epidote and sphene predominated in sedimentary periods of the Kongdian Formation, lower part of 4^th Member, 3^rd Member and 1^st Member, Shahejie Formation, which indicated these periods being violent mobilities in structures. The steady minerals gradually dominated in sedimentary period of the Guantao Formation from the bottom to the top, which comprehended the tectonic activity being gradually inactive again. The unsteady minerals gradually dominated again in sedimentary period of the Minghuazhen Formation, and showed the tectonic activity becoming strong in Neogene. Based on the contents of hematite and linonite, the palaeoclimate evolution of the Boxing Sag, Dongying Depression in Late Mesozoic--Cenozoic could be divided into five periods, namely, the sedimentary periods of the Late Mesozoic （humid to semi-humid） , the Kongdian Formation to the 4^th Member, Shahejie Formation（arid to semi-arid） , the 3^rd Member to 2^nd Member of Shahejie Formation（humid to semi-humid） , the 1 s, Member of Shahejie Formation（ arid to semi-arid）and the Guantao to Minghuazhen Formations（arid to semi-arid）.

关 键 词：碎屑重矿物 构造古地理 古气候 新生界 博兴洼陷 鲁西隆起 

分 类 号：P588.21[天文地球—岩石学]