Orogeny, orography, and the origin of the first rainforests: Paleobotany of the temporally-calibrated synorogenic Denver Basin, Colorado

造山作用、地形学和第一批热带雨林的起源：时间上的同生代丹佛盆地的古植物学，科罗多·柯克·约翰逊和罗伯特·雷诺兹EAR-0345910 EAR-0345910摘要时间校准的丹佛盆地的地层和植物化石提供了一个独特的、自然的实验室，在其中评估和量化退化、造山、地形和灭绝对古代生态系统演化的影响。来自盆地的证据表明，热带雨林生态系统最初是在白垩纪-第三纪(K-T)大灾难之后的极低生物多样性世界中隆起的拉莱姆前缘山脉东侧降雨量极高的地区进化的。该项目将检验三个主要假说：1.植物群和景观：植物群化石及其替代气候数据可以绘制到古地理图上，并与重要的环境事件联系起来，如西部内陆海道的退化、拉拉米亚造山运动和K-T灭绝事件，以提供对植物群、气候、生态系统和景观演变的洞察。热带雨林的起源：由拉莱姆造山运动和邻近的海道造成的地形条件导致局部高降雨量。这些条件，在古新世早期温暖但生物退化的后K-T世界，为热带雨林生态系统的演化奠定了基础。幽灵峡谷和古扇：由于山脉来源的河流水系被定位到切割的山谷中，在高起伏时期，冲积扇形成于同造山盆地的边缘。这些扇是古地貌特征，控制着古代植被模式，并强烈影响现代水文。该项目将整合古生物学、地质学和水文学的广泛领域的研究，以回答有关生物进化和灭绝的具体问题。这项工作还将提供与了解科罗拉多前线地区地下水资源的分布和数量直接相关的数据。

OROGENY, OROGRAPHY, AND THE ORIGIN OF THE FIRST RAINFORESTS: PALEOBOTANY OF THE TEMPORALLY-CALLIBRATED SYNOROGENIC DENVER BASIN, COLORADOKirk Johnson and Robert RaynoldsEAR-0345910ABSTRACTThe strata and fossil plants of the time-calibrated Denver Basin provide a unique, natural laboratory in which to evaluate and quantify the influence of regression, orogeny, orography, and extinction on the evolution of ancient ecosystems. Evidence from the basin suggests that the tropical rainforest ecosystem first evolved in areas of extremely high rainfall on the eastern flanks of the uplifting Laramide Front Range in the extraordinarily low biodiversity World that followed the Cretaceous-Tertiary (K-T) cataclysm. This project will test three major hypotheses:1. Floras and Landscapes: Fossil floras and their proxy climate data can be mapped onto paleogeography and linked to significant environmental events such as the regression of the Western Interior Seaway, the Laramide Orogeny, and the K-T extinction event to provide insight about the evolution of floras, climates, ecosystems and landscapes.2. Origin of Rainforests: Orographic conditions caused by the Laramide Orogeny and an adjacent seaway resulted in localized high rainfall. These conditions, in the warm but biologically depauperate post-K-T world of the early Paleocene, set the stage for the evolution of tropical rainforest ecosystems.3. Ghost Canyons and Ancient Fans: Alluvial fans form on the margins of synorogenic basins during times of high relief due to the localization of mountain-sourced river systems into incised valleys. These fans are paleogeomorphic features that controlled ancient vegetation patterns and strongly influence modern day hydrology.This project will integrate research across broad areas of paleontology, geology and hydrology to answer specific questions about biotic evolution and extinction on an evolving synorogenic landscape. This work will also provide data that is directly relevant to the understanding of the distribution and quantity of groundwater resources of the Colorado Front Range.