The Siwalik Group extending east-west collinear to the Himalayan southern front records Himalayan denudation history. In this study, we present sandstone petrography, heavy mineral assemblages, Nd isotopes and chemical composition of detrital garnet from the Siwalik succession along the Muksar Khola section. This study reveals the Tibetan Tethys Himalaya, Higher Himalayan Crystalline and Lesser Himalaya Sequence as the source of sediments and records a provenance change from the middle Miocene to Pliocene/Pleistocene. This was observed as a shift from shallow to deeper parts of the Higher Himalayan Crystalline as a source area around 10.6 Ma. The Lesser Himalaya Sequence supplied a significant amount of sediments after 7.5 Ma, but the deeper part was only exposed after the late Pliocene to Pleistocene. Around 4.0 Ma an increase in the sediments from the Higher Himalayan Crystalline was observed. This provenance study reveals two stages of the exhumation of the eastern Nepal Himalaya. The first occurred between 11.0 and 5.5 Ma and the second after 4.0 Ma, due to the activation of an out-of-sequence thrust known as the Sun Koshi Thrust, and formation of the Lesser Himalayan duplex respectively.

西瓦利克集团将东西线延伸到喜马拉雅南部前线，记录了喜马拉雅剥蚀的历史。在这项研究中，我们介绍了沿Muksar Khola断面的Siwalik演替过程中的砂岩岩石学，重矿物组合，Nd同位素和碎屑石榴石的化学成分。这项研究揭示了藏特提斯喜马拉雅山，喜马拉雅高结晶度和小喜马拉雅山序列作为沉积物的来源，并记录了从中新世中期到上新世/更新世的物源变化。观察到这是高喜马拉雅晶体从浅部向深部的转变，其源区约为10.6 Ma。小喜马拉雅山序列在7.5 Ma之后提供了大量的沉积物，但较深的部分仅在上新世晚期至更新世之后才暴露出来。大约4。观测到0 Ma时，喜马拉雅山高级结晶的沉积物增加。这项出处研究揭示了尼泊尔东部喜马拉雅山掘尸的两个阶段。第一次发生在11.0至5.5 Ma之间，第二次发生在4.0 Ma之后，这是由于分别被称为太阳高志推力的失序推力的激活和小喜马拉雅双峰的形成所致。