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秦岭造山带印支期造山作用控制着济源盆地的形成与演化,对盆地中沉积物物源进行研究,有利于恢复造山带造山-隆升的细节.通过对济源盆地中生代泥岩地球化学的系统分析,发现样品的CIA(化学风化指数)校正值在早-中三叠世、晚三叠世、早-中侏罗世和中侏罗世后期的平均值分别为68.5、76.4、86.0和73.7,这一演化特征可能反映其经历了古气候控制的化学风化过程.但是三叠纪样品CIA值明显过低,可能与源区活动的构造背景相关;ICV(成分变异指数)值显示沉积物具有初次沉积的特征,反映了源区早期发生过弧-陆碰撞或具备陆缘弧特征的克拉通基底隆升.而早-中侏罗世样品表现为高的CIA值,ICV值显示沉积物具有再循环特征,其初次沉积可能发生在弧后盆地中,后随造山带的隆升,被剥露再搬运而沉积下来.泥岩物源区构造环境判别结果显示,沉积物主要来自活动大陆边缘和被动大陆边缘,且含有较多大陆岛弧(陆缘弧)的信息.由此说明,中生代济源盆地盆缘构造活动经历了由克拉通基底隆升到造山带剥露的过程,这一过程与秦岭造山带印支期的造山作用密切相关.
The Indosinian orogeny of the Qinling orogenic belt controls the formation and evolution of the Jiyuan Basin and studies the sedimentary provenance in the basin is conducive to the restoration of orogenic or uplift details of the orogenic belt.Based on the systematic analysis of the Mesozoic mudstone geochemistry in the Jiyuan Basin The results showed that the correction values of CIA (chemical weathering index) were 68.5, 76.4, 86.0 and 73.7 respectively in the early-middle Triassic, Late Triassic, early-middle Jurassic and Middle Jurassic, This evolutionary feature may reflect the chemical weathering process under paleoclimate control, but the CIA value of the Triassic samples was significantly lower than that of the source region, and the ICV (compositional variation index) value indicated that the sediments had the first Sedimentary characteristics reflect the early craton basement uplift that occurred in the source area during the previous episode of arc-continent collision or continental arc, while the early-middle Jurassic samples show high CIA values, indicating that the sediments have a The primary sedimentation may occur in the backarc basin and later with the uplifting of the orogenic belt, which is deposited after being stripped and then transported.The structural environment of the mudstone provenance shows that the sediments mainly come from the active continental margin Passive continental margin and contains more continental island arcs (continental margins), indicating that the basin margin tectonic activity in the Jiyuan Basin experienced a process of uplift from the cratonic basement to the orogenic belt, Indosinian orogeny of the Qinling orogenic belt is closely related.