Defining and Modeling the Response of a Low Gradient Coastal System to Rapid Sea-Level Rise during the Late Pleistocene

在过去120年中，海平面上升的速度有所加快，从19世纪的全球速度约为零，到20世纪的平均速度约为1.7毫米/年，再到目前的3.4 +/-0.4毫米/年。对130，000年至80，000年前海平面高水位标志物的地质观察表明，全球海平面在数千年内达到约+2米的高度（相对于现代海平面），随后可能迅速上升至约+6米。这项提案的目标是确定北卡罗来纳州和弗吉尼亚州的海岸在这些时期对海平面变化的反应。该项目将收集北卡罗来纳州和弗吉尼亚州地区的地球物理数据和沉积物岩心。这些沉积物记录了过去海平面快速上升期间发生的侵蚀和沉积作用造成的变化，可以为该地区未来的状况提供模拟。 该项目为研究生和本科生提供培训。该提案将涉及了解低梯度海岸系统对海平面上升的地质和地貌动力学反应的目标。在东北卡罗来纳州和弗吉尼亚州，晚更新世海侵到高位沉积物发生在沿海平原和现代河口下的海洋同位素第5阶段古海岸线的向海方向。将在该区域的两个研究区收集地球物理数据和沉积物岩心。这些数据将在未来用于开发该地区相关系和层序地层框架的三维模型，开发数字水动力模型以了解沿海系统对海平面快速上升的反应，该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识产权进行评估来支持。优点和更广泛的影响审查标准。

Rates of sea-level rise have accelerated over the last 120 years, from global rates of approximately zero in the 19th century, to an average rate in the 20th century of approximately 1.7 mm/y, to the present rate of 3.4 +/- 0.4 mm/y. Geologic observations of sea-level high-stand markers from 130,000 to 80,000 years ago suggest that global sea level attained a height of approximately +2 m (relative to modern sea level) for several millennia, possibly followed by a rapid rise to approximately +6 m. The goal of this proposal is to determine how the coasts of North Carolina and Virginia responded to sea level changes during these times. This project will collect geophysical data and sediment cores in the North Carolina and Virginia region. The deposits contain a record of past changes due to erosion and sedimentation that occurred during rapid sea level rise that could provide an analog for future conditions in this region. The project provides training for graduate and undergraduate students. This proposal will address the objective of understanding the geological and morphodynamic response of a low-gradient coastal system to sea-level rise. In eastern North Carolina and Virginia, late Pleistocene transgressive to high-stand deposits occur seaward of the Marine Isotope Stage 5 paleoshoreline on the coastal plain and beneath the modern estuaries. Geophysical data and sediment cores will be collected in two study areas in the region. These data will be used in the future to develop a 3D model of facies relationships and the sequence stratigraphic framework of the region, to develop numerical hydrodynamic models to understand the response of the coastal system to rapid sea level rise, and to place vertical constraints on Pleistocene sea levels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.