龙门山前陆盆地南段须二段沉积特征

Sedimentary characteristics of second Member of Xujiahe Formationin in southern section of Mountain Longmen foreland basin

 邹任洲¹ 李勇¹ 熊鸿浩² 汪正江³ 王伟明¹ 罗峰¹

成都理工大学国家油气藏开发工程重点实验室，四川 成都 610059 东华理工大学地球科学学院，江西 抚州 344000 中国地质调查局成都地调中心，四川 成都 610081）

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, China Faculty of Earth Sciences, East China Institute of Technology, Fuzhou 344000, China Chengdu Center, China Geological Survey, Chengdu 610081, China)

 综合分析南段的测井、单井资料和野外实测5条剖面资料，利用野外实测剖面、测井曲线和岩石学特征综合分析的方法，得出龙门山前陆盆地南段须家河组二段的的沉积类型主要为辫状河三角洲和湖泊沉积。其中可识别出水上分流河道、河漫沼泽、水下分流河道、分流间湾、河口砂坝、远砂坝、滨湖沼泽和滨湖砂坝等微相。在此基础上，通过分析多口单井、野外实测剖面、砂体展布特征，并结合前人的研究成果，得出须二段沉积相空间展布：北部都江堰、郫县、新都地区和西南方向天全地区发育辫状河三角洲平原亚相，往南的新津、蒲江地区和西南雅安地区主要发育辫状河三角洲前缘亚相，南部的峨眉山等地区主要发育湖泊相。

 According to the comprehensive analysis of well logging, single well and field measured data of five sections, based on the method of field measured sections, well log curves and petrological characteristics, it is concluded that the sedimentary types of the second Member of Xujiahe Formation in the southern foreland basin of Mountain Longmen are mainly of the braided river delta and lake sediment. The microfacies of water distributary channel, river flood swamp, underwater distributary channel, distributary bay, mouth bar, far sand dam, lakeside swamp, lakeside bar can be identified. Through the analysis of single wells, the field measured sections, sand body distribution characteristics, and combining previous research results, the spatial distribution of sedimentary facies in the second Member of Xujiahe Formation is concluded: northern Dujiangyan, Pixian county, northern Xindu District and southwestern Tianquan Region developed braided river delta plain subfacies, southern Xinjin and Pujiang Regions and southwest part of Ya′an mostly developed braided river delta front subfacies, southern Mountain Emei District mainly developed lake facies.

10.6056/dkyqt201606002