Integrated stratigraphic, geomorphic, sedimentologic, numeric, and experimental study of hangingwall ramp architecture in continental half grabens

陆相半地堑上盘斜坡构造的地层学、地貌学、沉积学、数值和实验综合研究。该项目将地貌学和沉积学的野外研究与实验和计算方法相结合，以阐明构造和气候对不同沉降和倾斜的非海相伸展盆地地层层序发育的控制。该研究的动机是这样一种假设，即上盘斜坡上的不同沉降，或上盘斜坡上大型流域的沉积物通量，或两者兼而有之，控制了盆地大部分地区的沉积堆积、地层结构、沉积物保存和沉积物口径，以及不整合面和沉积旁道面的发育。预测特定相模式的数值模拟将使用实验方法和在新墨西哥州里约热内卢大裂谷的一个绘制良好、年代确定的伸展盆地收集的现场数据进行测试。新的磁地层资料将加强该项目所需的年代数据库。PIs的研究方法与传统地层学方法的不同之处在于，它将地貌学和地层学方法结合起来，模拟沉积大陆序列，预测半地堑背景下沉积物的扩散模式。由此产生的对盆地填充结构起源的见解将对美国干旱西部含水层结构的概念化产生直接影响。

Integrated stratigraphic, geomorphic, sedimentologic, numeric, and experimental study of hangingwall ramp architecture in continental half grabens.ByGary A. Smith and John W. GeissmanEAR-0344146This project integrates geomorphic and sedimentologic field studies with experimental and computational approaches to elucidate tectonic and climatic controls on the development of stratigraphic sequences within differentially subsiding and tilting, nonmarine extensional basins. The research is motivated by the hypothesis that differential subsidence across the hangingwall ramp, or sediment flux from large drainage basins on the hangingwall ramp, or both, controls the accumulation, stratigraphic architecture, sediment preservation, and caliber of sediment throughout much of the basin, as well as the development of unconformities and sedimentary bypass surfaces. Numerical simulations predicting specific facies patterns will be tested using experimental methods and field data collected in a well-mapped, well-dated extensional basin in the Rio Grande rift of New Mexico. New magnetostratigraphic data will enhance the chronological database required for the project. PIs research approach differs from traditional stratigraphic methods primarily through integration of geomorphic and stratigraphic methods for modeling aggrading continental successions to predict patterns of sediment dispersal in half graben settings. The resulting insights into the origin of basin-fill architecture will have immediate implications for conceptualizing aquifer structure in the arid western United States.