Collaborative Research: Reconstruction of a continuous, high-resolution record of late Quaternary paleohydrology and paleoclimate of the Amazon basin

该奖项将提供资金重建亚马逊盆地3万年的高分辨率气候变化记录，并从化石有孔虫地球化学中重建赤道大西洋西部南北海表温度梯度的高分辨率记录。现场工作将包括亚马逊海底峡谷和扇复合体北部和南部上部大陆斜坡的高分辨率Chirp地震反射剖面，以确保在取心点连续和整合沉积，并使用R/V Knorr上新的长芯取心能力收集一套新的活塞芯和地面多芯。分析研究将集中于两个“目标”岩心，一个在亚马逊扇的北部，一个在亚马逊扇的南部，利用粘土矿物学来阐明陆地沉积物来源，配对分析浮游有孔虫的微量元素比率（Mg/Ca和Ba/Ca）和氧同位素来确定百年尺度分辨率的海温和盐度（SSS）。作为SST和SSS的补充措施，将对藻脂进行Alkenone Uk37和D/H分析。最后，将进行丰度分析和陆源植物蜡的D/H和d13C测量，以评估冰川-去冰川-全新世气候过渡期间大陆水文和植被的变化。pi还将产生花粉时间序列，以确定主要植被类型的变化是否与气候变化有关。更广泛的影响包括与巴西科学家密切相关的国际合作，研究生和本科生参与这项研究的所有阶段，以及对地球关键热带地区气候变率的研究。

Baker/Hollander AbstractThis award will provide funds to reconstruct a high-resolution, 30,000 year record of Amazon Basin climate change and to reconstruct a high-resolution record of the North-South sea surface temperature (SST) gradient of the western equatorial Atlantic from fossil foraminifera geochemistry. Fieldwork will consist of high resolution Chirp seismic reflection profiling of the upper continental slope north and south of the Amazon submarine canyon and fan complex to ensure continuous and conformable sediment deposition at the coring site and the collection of a new suite of piston cores and surface multi cores using the new long coring capability on the R/V Knorr. Analytical research will focus on two "target" cores, one north and one south of the Amazon fan, employing clay mineralogy to elucidate terrestrial sediment sources, paired analyses of planktonic foraminifer with minor element ratios (Mg/Ca and Ba/Ca) and oxygen isotopes to determine SST and salinity (SSS) at centennial scale resolution. Alkenone Uk37 and D/H analyses on algal lipids will be conducted as complementary measures of SST and SSS. Finally, abundance analysis and D/H and d13C measurements of terrigenous plant waxes will be conducted to assess continental hydrological and vegetation variability across the glacial-deglacial-Holocene climatic transition. The PIs will also produce a pollen time series to determine whether changes in major vegetation type were associated with changes in climate. Broader Impacts include a tightly linked international collaboration with Brazilian scientists, the involvement of graduate and undergraduate students in all phases of this research and the study of climate variability in a critical tropical region of the planet.