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

造山作用、地形学和第一批雨林的起源：科罗拉多州丹佛盆地的时间校准的同生古植物学柯克约翰逊和罗伯特Raynoldsstrike-0345910摘要丹佛盆地的地层和植物化石提供了一个独特的自然实验室，可以评估和量化退化、造山、地形学和灭绝对古代生态系统演化的影响。 来自该盆地的证据表明，热带雨林生态系统首先在拉腊米德山脉东侧的降雨量极高的地区进化，该山脉位于生物多样性极低的世界，随后发生了第三纪（K-T）灾难。 本项目将测试三个主要假设：1。植物和景观：化石植物群及其代用气候数据可以被映射到古地理学上，并与重要的环境事件相联系，如西部内陆航道的退化、Laramide造山运动和K-T灭绝事件，以提供关于植物群、气候、生态系统和植被演化的见解。热带雨林的起源：由Laramide造山运动和邻近的海道造成的地形条件导致了局部的高降雨。 在古新世早期温暖但生物不发达的后K-T世界，这些条件为热带雨林生态系统的进化奠定了基础。古冲积扇和古扇：冲积扇形成于同造山盆地的边缘，在高地形时期，由于山源河流系统局部化为下切河谷。 这些扇是古地貌特征，控制着古代植被格局，并强烈影响着现代水文。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特定问题。 这项工作还将提供与了解科罗拉多前岭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.