| Situated in south of Himalayas-the loftiest mountain ranges in the world, Bay of Bengal hosted most of erosion products from Himalayan and Tibetan Plateau. As the result, an enormous submarine sedimentary fan, as so called "Bengal Fan" has been deposited in the floor of Bay of Bengal. There is a clear relationship between Bengal Fan and Himalayas-Tibetan Plateau in the cause of terrigenous deposits erosion, delivery and sedimentation. During the formation of Bengal Fan, the greatest turbidite body in the world, turbidity currents sedimentation is the main dynamics to build the sedimentary framework. So the sedimentation rate of the fan is relatively high and it can be regarded as an ideal subject to carry out short-term and high-resolution paleoclimatic research. Ninetyest (90°E) Ridge is a submarine mountains of the Bay of Bengal. It is mainly documented by pelagic and himipelagic sedimentation. So the sedimentation rate of the ridge area is relatively low. On the other hand, this area is minor reformed by turbidity and bottom currents activity, so it contains some initial information of the sedimentary process. As such, it can be served as an ideal situation to so some long-term research on paleoceanography.Many proxy records have been developed to define the change of paleoclimate and paleocanograpphy. Here we present the stable isotope, weight content of CaCO3, magnetic susceptibility and grain size records of MD77190, MD81345 from the Bengal deep sea fan and DSDP216, DSDP217, ODP758, MD81349 from the Ninetyest Ridge to discuss the response of the sedimentary records to the rapid uplift of Himalayas and Tibetan Plateau. The coupling relationship of the global or regional paleoclimatic and paleoceanographic changes, such as mid-Plestocene Transition, mid-Brunhes Dissolution Event and the rapid climate variability during the last glaciation have also been discussed. The results shoe that the sedimentary records of the studied region have well documented not only the rapid uplift of Himalayas and Tibetan Plateau over the past 5.2Ma, but also the mid-plestocene transition and mid-Brunhes dissolution event, The results also suggest that the climatic changes in the low latitudes have a good response not only to the glacial-interglacial cycles and climatic instability in the high latitudes, but also to insolation of summer in the low latitudes.Firstly, basted on the theory analysis and comparison, we make a discussion about the climatic implications that the proxy indicators bear and the regional evolution concerned. Then we argue the Paleoclimatic and paleoenvironmental changes of the studied region since Pliocene time. The changes of magnetic susceptibility, mass accumulation rate (MAR) of CaCO3 and non-CaCO3 MAR form ODP site758 indicate that the loaded terrigenous sediments increased at 5.1MaB.R, 3.9-3.4 MaB.R, 1.7MaB.P. and 0.8MaB. P. These accompanied the rapid uplift of Himalayas since Pliocene. Among the four changes, the last two changes were relatively obvious; they indicate that the two uplifts were relatively significant. The last three changes coincided with the uplifts of Tibetan Plateau, so called "Episode A of Qinghai-Tibet Movement (3.6MaB.P.)", "Episode A of Qinghai-Tibet Movement (1.7MaB.P.)" and "Kunlun-Huanghe Movement (1.2-0.6MaB.P.) and thelast two changes coincided with the main period transition of the Indian monsoon. These suggest that the sedimentary records of the studied area have response to the uplifts of Himalayas and Tibetan Plateau and changes of paleoclimate. It can be regarded as a "watch" of the uplift. The changes of the CaCO3 content, coarse fraction (>150nm) content and planktonic foraminifer faunal variations from ODP site758 show that the dissolution of CaCO3 was great during 0.55-0.4MaB.P.. Because the first two proxy indicators clearly decreased and the amount of dissolution-sensitive species reduced, in the same time, the amount of dissolution-resistant species increased in this period. The event has been found in Atlantic Ocean, Pacific Ocean, the oth...
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