冀北坳陷长龙山组沉积相与地球化学特征研究  

Study on sedimentary facies and geochemical features of Changlongshan Formation in Jibei Depression

作　　者：陈小军[1] 罗顺社[1] 张建坤[1] 王丽云 

机构地区：[1]长江大学油气资源与勘探技术教育部重点实验室,湖北荆州434023 [2]中国石油东方地球物理公司研究院乌鲁木齐分院,新疆乌鲁木齐830016

出　　处：《断块油气田》2010年第3期270-273,共4页Fault-Block Oil & Gas Field

基　　金：中国石油化工集团公司海相油气勘探前瞻性项目"燕山地区中新元古界沉积相与层序地层学研究"(GO800-06-ZS-350)

摘　　要：通过对野外剖面、室内薄片资料的研究和岩性特征及相标志的分析认为,长龙山期海侵范围急剧扩大,形成了一套成熟度较高的滨浅海相碎屑岩沉积,可划分为无障壁海岸和浅海陆棚2个相区:前者主要发育在下部,进一步可细分为前滨、近滨2种亚相;后者主要发育在上部,以滨外陆棚亚相为主。地球化学特征分析表明,微量、常量元素平均质量分数具有相同的变化规律,且所反映的沉积环境与宏观结论相一致,表现为前滨较高,至近滨骤减,在滨外陆棚激增,这与近滨沉积期海平面发生较大幅度的下降及整个长龙山期有大量陆源物质侵入直接有关。上述分析讨论为进一步研究该区沉积相特征及有利储集相带的预测奠定了基础。After observing field profile,studying slices and analyzing the lithology and facies indices of Changlongshan Formation,it is considered that its scope of transgression spreads rapidly and forms a set of higher-maturity littoral-neritic facies sedimentary rocks.Changlongshan Formation can be divided into barrierless coast and neritic shelf facies.The former mainly develops in the lower part,which can be further subdivided into foreshore and nearshore subfacies.The latter mainly develops in the upper part and dominated by offshore shelf subfacies.Geochemical behavior analysis shows that the average content of trace and major elements has the same variation law,and the reflected sedimentary environment is consistent with the macro conclusions with higher content in foreshore,abruptly decreasing in nearshore and surging in offshore shelf subfacies that has a direct relationship with nearshore sedimentary period of large drop in sea level relatively and the intrusion of a large number of terrestrial materials in the whole Changlongshan period.Combined with the above study,the depositional model and evolution characteristics of Changlongshan Formation are proposed,which can provide a basis for further study on the sedimentary facies characteristics and prediction of favorable facies belts of the reservoir.

关 键 词：沉积相 地球化学特征 沉积模式及演化 长龙山组 冀北坳陷 燕山地区 

分 类 号：TE122[石油与天然气工程—油气勘探] P512[天文地球—地质学]