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对天山南麓库车坳陷砂岩全岩主元素分析表明, 沉积记录在下三叠统-中三叠统、上侏罗统-下白垩统、下白垩统-古新统、中新统-上新统等4个界面发生较大变化或突变, 这与砂岩骨架、碎屑重矿物的成分(组合)变化基本一致. 中生代~新生代沉积过程呈5段式发展: (1) 碎屑组合主要表现为从褐红色粗碎屑沉积到灰色-深灰色细碎屑沉积、红色中-细碎屑沉积、红色-杂色碎屑夹膏盐沉积, 最后转变为褐灰色粗碎屑沉积, 岩屑成分成熟度相应呈不稳定-稳定-不稳定-较不稳定- 极不稳定组合产出, 后晚侏罗世以碳酸盐岩等沉积岩岩屑的增加为显著特征; (2) 砂岩全岩的CaO和Fe2O3*+MgO 含量呈较高值-低值-高值-较高值-最高值序列变化, 后晚侏罗世急剧增高; (3) Al2O3/(CaO+Na2O)和 ln(Q/(L+CE))等反映碎屑成分风化指数的综合指标也呈较低值-高值-低值-较低值-最低值变化, 在后晚侏罗世显著降低. 第1和第2阶段和后 3 个阶段样品在 A-CN-K 和A-CNK-FM图上明显可分. 研究表明, 早-中三叠世、晚侏罗世-早白垩世是研究区古构造-古气候重要的变革期或转折期, 而晚白垩世、中-上新世前后不同的沉积体系域和类似的砂岩风化指数说明主要与古构造变动即山盆差异升降有关.
Analysis of the main rock elements in the Kuqa sag in the southern foot of the Tianshan Mountains shows that the sedimentary records were recorded in Lower Triassic-Middle Triassic, Upper Jurassic-Lower Cretaceous, Lower Cretaceous-Paleo-Cenozoic, and Middle Miocene- (4) The changes of the four interfaces of the sandstone framework and the detrital heavy minerals are basically the same, and the depositional processes of the Mesozoic to Cenozoic are developed in five stages: (1) The main combination of detrital assemblages The results show that from coarse reddish brown sediments to gray-dark gray fine detrital sediments, red medium-fine detrital sediments, red-variegated detritus salt deposits, and finally into brown-gray coarse detrital sediments, cuttings The compositional maturity is correspondingly unstable - stable - unstable - less stable - very unstable combination output, and later Late Jurassic is characterized by the increase of lithic fragments such as carbonate rocks; (2) (CaO + Na2O) and ln (QO) in the late Jurassic range from high value to low value to high value to high value to the highest value. / (L + CE)), etc. The comprehensive index reflecting the weathering index of detritus also showed the lower value - high value - low value - low value - the lowest value change. In the late Jurassic Significantly decreased.The samples in the first and second stages and the last three stages were clearly distinguishable on the A-CN-K and A-CNK-FM maps.The results show that the Early-Middle Triassic, Late Jurassic-Early Cretaceous The Cenozoic is an important paleo-climate change or turning point in the study area. The sedimentary system and similar sandstone weathered indices before and after the Late Cretaceous, Meso-Pliocene are mainly explained by paleo- related.