澳大利亚North Carnarvon盆地晚三叠世Mungaroo组大型浅水辫状河三角洲沉积充填特征及模式  

Large-scale shallow braided river delta depositional characteristics and depositional pattern of Mungaroo Formation in Late Triassic, North Carnarvon Basin, Australia

作　　者：夏晨晨 朱红涛[1,2] 杨香华[1,2] 黄众 庄文娟[4] 曹秀荣[1,2] 曾智伟[1,2] 

机构地区：[1]中国地质大学构造与油气资源教育部重点实验室,湖北武汉430074 [2]中国地质大学资源学院,湖北武汉430074 [3]中海油研究总院,北京100027 [4]华北油田公司勘探开发研究院,河北任丘062550

出　　处：《中南大学学报（自然科学版）》2015年第8期2983-2991,共9页Journal of Central South University:Science and Technology

基　　金：国家科技重大专项(2011ZX05030);教育部科技项目霍英东教育基金会资助项目(132020)~~

摘　　要：对澳大利亚North Carnarvon盆地三叠纪Mungaroo三角洲的钻井、地震、岩心、薄片等资料进行分析,结合季风强盛期、减弱期、间歇期的气候交替变化,建立研究区不同季风阶段对应的浅水辫状河三角洲的沉积充填序列、迁移演化规律,并总结其沉积模式。研究结果表明:Mungaroo三角洲具有以下典型沉积特征:主体发育三角洲平原相带,普遍发育正粒序河道充填沉积;河道砂岩与富有机质泥岩(薄煤层)频繁互层;碎屑颗粒分选和磨圆均较差,但石英颗粒含量较高;主要发育平行-亚平行地震相,局部发育叠瓦状前积地震反射;季风性气候控制明显,高山植物孢粉与低地植物孢粉交互式变化。The drilling, seismic, cores and thin section data of Mungaroo delta in North Carnarvon Basin of Australia were analyzed. Sedimentary sequence and migration evolution of shallow braided river delta in different monsoon stages were built through the sedimentary background, sedimentary features and intermittent stage of monsoon climate change, and the depositional model of Mungaroo Formation, North Carnarvon Basin was built. The results show that Mungaroo delta has five typical sedimentary characteristics： Delta plain facies is well developed and normal graded channel deposition is widespread; Channel sandstone and the mudstone rich of organic matter are interbedded frequently; Clast granules are poorly sorted and rounded but rich of quartz granule; Mungaroo Formation in late Triassic generally develops parallel-subparallel seismic facies and locally imbricate progradation reflection seismic facies; Sporopollen of alpine vegetation and lowerland plant changes interactively under the control of monsoon climate.

关 键 词：浅水辫状河三角洲 季风气候 沉积充填演化 Mungaroo组 NORTH Carnarvon盆地 

分 类 号：P534.51[天文地球—古生物学与地层学]