天山北缘辫状河型洪积扇沉积特征及其对准噶尔盆地西北缘古代洪积扇油气勘探的指导意义  

Sedimentary Characteristics of Braided Alluvial Fan in North Tianshan Mountain and Its Significance for Oil-gas Exploration of Ancient Alluvial Fans in Northwest Junggar Basin

作　　者：余宽宏 金振奎[2] 李桂仔[3] 何苗 郭秀娟[2] 杨婷[2] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266580 [2]中国石油大学(北京)地球科学学院,昌平102249 [3]中海油能源发展股份有限公司工程技术分公司,天津300457

出　　处：《高校地质学报》2015年第2期288-299,共12页Geological Journal of China Universities

基　　金：山东省自然科学基金青年基金(ZR2014DQ016);国家重点基础研究发展计划(973)(2014CB239002);中国石油大学(华东)科研启动基金(Y1301058)联合资助

摘　　要：通过天山北缘白杨河及玛纳斯河现代辫状河沉积作用为主的洪积扇的研究,认为此类洪积扇以活动的辫流带和洪水期才发生沉积的漫洪带为特征。扇面上不能全区同时发生沉积,而是选择扇面低势能区发生沉积。辫状河道呈条带状分布,与常规砾质辫状河沉积特征类似,并向扇缘散开,沉积的砾石条带物性好。洪积扇的发育受构造、气候、水系的共同控制,这些条件决定了洪积扇的沉积特征及发育规模。准噶尔盆地西北缘三叠系古代洪积扇以辫状河道沉积作用为主,是发育在盆地边缘低坡度洪积扇,更倾向于辫状河沉积特征。This study was based on field study on Baiyanghe and Manas alluvial fans in North Tianshan Mountain. Braided belt is the main sedimentary area on the surface of arid braided alluvial fan. Sediments were unloaded in low potential area and sedimentary area laterally migrated along with the low potential area migrated. Braided channels show as string on the surface of alluvial fan and distributed in a wider area in the margin of fan. Gravel sediments in the braided belt have good porosity and permeability. Sedimentary characteristics and scale of alluvial fans are controlled by tectonic activities, climatic conditions, provenance supplies and river system.Braided alluvial fans are main ancient alluvial fans types in the northwest Junggar Basin and they occurred in the basin margin, showing more sedimentary characteristics of braided river.

关 键 词：天山北缘 辫状河型洪积扇 准噶尔盆地 古代洪积扇 

分 类 号：P618.13[天文地球—矿床学]