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通过对准噶尔西北缘和什托洛盖盆地新近系白杨河剖面详细的沉积学和磁组构的研究,探讨了准噶尔西北部山地约7Ma以来的构造变化.白杨河剖面由下至上可划分为塔西河组、独山子组和西域组,分别对应于浅湖相、扇三角洲相和砾质辫状河相.古流向和砾石成分分析表明,剖面物源来自和什托洛盖盆地北侧山地.根据沉积学和磁化率与磁组构参数(P j、T、L和F)的变化,准噶尔西北部地区约7Ma以来的构造-环境演变可划分为3个阶段:阶段Ⅰ(6.80~3.50Ma):浅湖相,磁化率和磁组构参数值为剖面最低,且变化幅度很小,代表了构造环境比较稳定,地势高差较小或物源区较远;阶段Ⅱ(3.50~2.58Ma):扇三角洲相,沉积速率、磁化率和磁组构参数值显著增大,表明准噶尔西北部山地强烈隆升;阶段Ⅲ(<2.58Ma):砾质辫状河相,磁化率和磁组构参数值进一步增大,可能是构造隆升与气候变化共同作用的结果.3.50Ma准噶尔西北部山地强烈的构造隆升与天山地区和青藏高原周缘约3.00~4.00Ma的构造隆升具有准同时性,是印度-欧亚板块陆内俯冲挤压远程效应表现.
Based on the detailed sedimentary and magnetic organization of the Neogene Beiyang section in the northwestern margin of Junggar and the Shittoruai Basin, the tectonic changes since about 7 Ma in the northwestern Junggar have been discussed. The Baiyanghe section can be divided into towers Xihe Formation, Dushanzi Formation and Western Formation respectively correspond to shallow lacustrine facies, fan deltaic facies and gravel braided river facies.The analysis of paleocurrent and gravel composition shows that the source of the profile comes from the mountainous side of the northern side of the Straitloag Basin The changes of sedimentology and magnetic susceptibility and magnetic fabric parameters (P j, T, L and F) and the tectonic-environmental evolution since about 7 Ma in the northwestern Junggar can be divided into three stages: Stage Ⅰ (6.80-3.50 Ma) : Shallow lacustrine facies, magnetic susceptibility and magnetic structure parameters of the lowest profile, and the magnitude of change is small, representing the relatively stable tectonic environment, small terrain elevation or source area far; stage Ⅱ (3.50 ~ 2.58Ma) : The fan delta facies, deposition rate, magnetic susceptibility and magnetic parameter increase significantly, indicating strong uplift in the northwestern part of Junggar. Stage III (<2.58Ma): gravelly braided river facies, magnetic susceptibility and magnetic structure parameters Further increase in value may be due to tectonic uplift and co-operation with climate change The result .3.50Ma northwestern Junggar mountain intense tectonic uplift and Tianshan area and the periphery of the Tibetan Plateau tectonic uplift of about 3.00 ~ 4.00Ma quasi simultaneity, India - subduction squeeze remote effect performance within the Eurasian land.