NSFGEO-NERC: Impact of the Plio-Pleistocene Transition on Provenance and Sediment Routing from the Himalaya to the Deep-Sea Bengal Fan

喜马拉雅山脉代表着地球上最大的山脉，主要居住在尼泊尔、印度、巴基斯坦和中国。喜马拉雅山脉在数百万年前印度与亚洲相撞时开始上升，这改变了地球的气候，改变了海洋循环和化学物质，并影响了生物进化的进程。喜马拉雅山脉的侵蚀导致了地球上最大的沉积物堆积在孟加拉湾，即深海孟加拉扇。在这个沉积物记录中隐藏着喜马拉雅山脉的历史--现在被侵蚀的山峰。过去的珠穆朗玛峰，埋在大陆架和印度洋最深部分的沉积物下。2015年，一支由多国组成的探险队在一艘专门设计的钻井船“乔伊德斯决议号”上发现了长达1.5英里的钻芯，其中包含了这一记录。新的研究将利用这些岩心的沉积物来追踪喜马拉雅山脉侵蚀的历史，以及世界上最大的两条河流--恒河和雅鲁藏布江--是如何在过去300-500万年间将沉积物输送到孟加拉湾的。像喜马拉雅山脉这样的巨型山脉在地质史上是罕见的，但没有喜马拉雅山脉就没有湿润的亚洲季风，没有肥沃的洪泛平原或含水层，就没有古老的印度河文明，也没有山脉。世界上那个地方的珠穆朗玛峰。因此，这项研究的结果将告诉我们气候变化、景观演变，以及世界上人口最稠密的地区之一是如何形成我们今天所看到的。以这种方式了解过去，可以帮助我们更好地了解生活在这一令人难以置信的地理特征影响下的10%世界人口的未来。

The Himalayas represent the largest mountain chain on Earth, and reside mostly in Nepal, India, Pakistan and China. The Himalayas began rising many millions of years ago when India collided with Asia, which changed Earth's climate, altered ocean circulation and chemistry, and impacted the course of biological evolution. Erosion of the Himalayas resulted in deposition of the largest pile of sediment on the planet in the Bay of Bengal, the deep-sea Bengal Fan. Within this sediment record lies the history of the Himalayas - the now eroded Mt. Everests of the past, buried under sediment of the continental shelf and the deepest parts of the Indian Ocean. In 2015, a multi-national expedition on the Joides Resolution, a specially designed drill ship, recovered ~1.5 miles of drill core that contains this record. New research will use sediment from these cores to trace the history of Himalayan erosion and how two of the world's largest rivers, the Ganges and Brahmaputra, delivered this sediment to the Bay of Bengal over the last 3-5 million years. Giant mountain ranges like the Himalayas are a rarity through geologic history, but without the Himalayas there are no drenching Asian monsoons, no fertile floodplains or aquifers, no ancient Indus Civilization, and no Mt. Everests in that part of the world. The results of this research will therefore tell us about climate change, landscape evolution, and how one of the world's most densely populated areas came to be as we see it today. Understanding the past in this way can help us better understand the future for the 10% of the world's population that lives under the influence of this incredible geographic feature.