Collaborative Research: Holocene Geology and Anthropology: Paleoclimate, Landscape Evolution, and Human Occupation of the Western Lake Titicaca Basin, Peru

合作研究：全新世地质学和人类学：秘鲁西喀喀湖盆地的古气候、景观演化和人类居住

• 批准号: 0227550
• 负责人: Paul Baker
• 金额: $ 14.06万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0227550&HistoricalAwards=false
• 关键词: Collaborative; Research; Holocene; Geology; Anthropology

ABSTRACTThe ultimate goal of this collaborative study is to determine how Holocene climate variability affected landscape evolution in tributary valleys of the western Lake Titicaca basin and how Holocene landscape evolution in those tributaries influenced human activities. To meet this goal we will work at the intersection of three disciplines: paleoclimatology, fluvial sedimentology, and archaeology. We will create a proxy-based, high-resolution (decadal), properly interpreted paleoclimate time series for the western Lake Titicaca basin by collecting and analyzing sediment cores from small, high-sedimentation-rate lakes. We will generate new sedimentologic and geomorphic data, from three river valleys in the same region, and use those data to create a basinwide model of fluvial evolution in the context of regional climate change and base level. And, we will generate new archaeological data that will begin to fill the gaps in our knowledge of the early prehistory (especially the record of the Archaic Period, ca. 10,000 to 3500 cal BP) of the basin. These data will address important questions about the character of the initial occupation of the basin, the dynamics of the sedentarization process, and the expansion of agropastoral settlements following sedentarization.In this study we aim to produce the best-dated and best-understood reconstruction of Holocene precipitation in tropical South America. This record is needed to answer important paleoclimate questions (such as the nature of the sea-surface temperature forcing of the tropical atmosphere), but it also essential to our ultimate research goal. Once climate variability is securely known, we can address questions concerning the evolution of fluvial landscapes within the proper climatological context. Holocene fluvialsedimentology in the western Titicaca basin is largely controlled by precipitation variability, which affects both riverine discharge and base level (the level of Lake Titicaca). Few studies of fluvial evolution have been done with the complete knowledge of the relevant records of both climate and base level, so this is an unusual opportunity to increase our understanding of both the rates and processes of sediment aggradation and downcutting, as well as possible non-linearities in the fluvial response to climate and base-level variability. Because fluvial variability is a key factor in both landscape evolution and the lives of both modern and ancient occupants of the basin, a secure knowledge of climate and landscape variability will allow us to address serious issues relating climate change and human activities. The new archaeological data we will collect will complement ongoing work elsewhere in the basin and the data, gathered within a highly resolved paleoclimatic context accompanied by a well-constrained reconstruction of natural landscape evolution, unrivaled in many other research settings, will allow us to document the relative timing of environmental and cultural change.

这项合作研究的最终目标是确定全新世气候变化如何影响西部喀喀湖盆地支流山谷的景观演变，以及这些支流的全新世景观演变如何影响人类活动。为了实现这一目标，我们将致力于三个学科的交叉：古气候学、河流沉积学和考古学。我们将通过收集和分析来自小的、高沉积速率的湖泊的沉积岩芯，为西部的喀喀湖盆地创建一个基于替代的、高分辨率(十年制)、适当解释的古气候时间序列。我们将从同一地区的三个河流流域产生新的沉积学和地貌数据，并使用这些数据在区域气候变化和基准面的背景下创建一个盆地范围的河流演变模型。而且，我们将产生新的考古数据，开始填补我们对盆地早期史前(特别是约10,000至3,500卡BP的古代时期的记录)的知识空白。这些数据将解决有关盆地最初被占领的特征、定居过程的动态以及定居后农牧定居点的扩张等重要问题。在这项研究中，我们的目标是重建南美洲热带地区全新世降水的最新日期和最好的理解。这一记录对于回答重要的古气候问题(如热带大气海洋表面温度强迫的性质)是必要的，但对于我们最终的研究目标也是必不可少的。一旦气候变异性得到可靠的了解，我们就可以在适当的气候学背景下解决有关河流景观演变的问题。喀喀湖盆地西部全新世河流沉积学在很大程度上受降水变化的控制，降水变化对河流流量和基准面(喀喀湖水位)都有影响。在完全了解气候和基准面的相关记录的情况下，很少对河流演变进行研究，因此，这是一个不同寻常的机会，可以增加我们对沉积物堆积和下切的速度和过程以及河流对气候和基准面变化的响应中可能的非线性的了解。由于河流变化是景观演变和盆地现代和古代居住者生活中的一个关键因素，对气候和景观变化的可靠知识将使我们能够解决与气候变化和人类活动有关的严重问题。我们将收集的新考古数据将补充盆地其他地方正在进行的工作，在高度分辨的古气候背景下收集的数据，以及对自然景观演变的严格限制的重建，将使我们能够记录环境和文化变化的相对时间。