Collaborative Research: Neogene history of mass transport deposits offshore North Carolina

合作研究：北卡罗来纳州近海大规模运输沉积物的新近纪历史

• 批准号: 2140398
• 负责人: Anne Becel
• 金额: $ 73.03万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2140398&HistoricalAwards=false
• 关键词: Collaborative; Research; Neogene; history; mass

Submarine landslides are a common seafloor feature of the North Atlantic passive margin on both sides of the ocean; their presence on the Eastern North American Margin is the rule rather than the exception. They threaten large population centers along these coasts with possible tsunamis, and move material from the shallow to the deep sea during margin evolution. Despite their high prevalence on passive margins and in particular, on the U.S. east coast, very little about their causes, mechanical behavior, and frequency is understood, and their role in the development of the passive margin as it exists today has not been examined. This project will collect new seismic data with the R/V Marcus Langseth to examine large submarine landslide behavior over the past 23 million years in a region offshore North Carolina that has experienced large, recent submarine landslides. Sediment cores will be retrieved from the Cape Fear Slide, which is the most recent large submarine landslide in the area and still expressed on the seafloor. The cores will provide insights into pre-conditioning and triggering mechanisms. This study will improve understanding of how slope failures operate through time and the manner in which past events might influence subsequent events, and will provide training and international collaboration opportunities for three graduate students and three early-career scientists.This project will collect high-resolution multichannel seismic data and piston cores on the continental rise and slope in the vicinity of the Cape Fear submarine landslide offshore North Carolina. These data will be used to examine the interplay between margin topography, fluid and heat flow, pore pressure, and submarine mass transport deposits. Mass transport deposits, bottom-simulating reflections, and stratigraphic sequences in the Cape Fear region will be seismically imaged. The new high-resolution seismic data will be combined with existing seismic and borehole data to interpret number of events, timing, source areas, volumes, areal extent and runout length, and bounding surfaces of mass transport deposits. The seismic data will be used to assess and model internal characteristics of mass transport deposits and surrounding sediments, including deformation style, present-day pore pressure and temperature distribution, and the presence of gas. This project consists of acquiring 3843 km of 2D high-resolution multichannel seismic data, along with bathymetry, subbottom profiler, and water column data. Seven piston and seven gravity cores will be collected in locations associated with seeps or bottom-simulating reflections. Geotechnical and pore fluid chemical analyses will be performed. The processed seismic data will be interpreted for stratigraphic age control, areal extent, and volume of mass transport deposits. Internal deformation of mass transport deposits will be examined through seismic attribute analysis. Sediment physical properties will be derived using full waveform inversion and quantitative models of conditions for failure will be developed. The results of this project will be relevant to understanding submarine landslides dynamics on passive margins with similar characteristics worldwide.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.

海底滑坡是北大西洋两侧的北大西洋的常见海底特征。他们在北美东部的边缘的存在是规则，而不是例外。他们以可能的海啸威胁了沿这些海岸的大型人口中心，并在边缘进化期间将材料从浅海移至深海。尽管它们在被动边缘，尤其是在美国东海岸的高度流行，但对它们的原因，机械行为和频率的了解很少，而且它们在今天存在的被动边缘发展中的作用尚未被检查。该项目将使用R/V Marcus Langeth收集新的地震数据，以检查过去2300万年的大型海底滑坡行为，该地区在北卡罗来纳州近海地区经历了最近的海底陆地坡道。将从Cape Fear Slide取回沉积物核心，这是该地区最近大型海底滑坡，仍在海底表达。核心将提供有关预先调节和触发机制的见解。这项研究将提高人们对斜率失败如何随着时间的流逝以及过去事件影响后续事件的方式的理解，并将为三个研究生和三名早期职业生涯的科学家提供培训和国际协作机会。该项目将收集高分辨率的多通道地震数据和活塞核心，并在大陆上升起和slope cape Cape Fear Fear cape cape offersarine landsarine northsaline northsare northsare northsare northsare northshore northshore。这些数据将用于检查边缘地形，流体和热流，孔隙压力和海底大量运输沉积物之间的相互作用。质量恐惧区域中的质量运输沉积物，底部模拟的反射和地层序列将进行地震成像。新的高分辨率地震数据将与现有的地震和钻孔数据相结合，以解释事件，时机，来源区域，体积，面积和跳动长度以及大规模运输沉积物的边界表面。地震数据将用于评估和模拟质量传输沉积物和周围沉积物的内部特征，包括变形样式，当今的孔隙压力和温度分布以及气体的存在。该项目包括获取3843公里的2D高分辨率多通道地震数据，以及测深，Subbottom Profiler和水柱数据。将收集七个活塞和七个重力核心在与渗漏或减少底部反射相关的位置中收集。将进行岩土液和孔隙流体化学分析。处理后的地震数据将被解释，以用于地层年龄控制，面积范围和大众传输沉积物的体积。将通过地震属性分析检查大众传输沉积物的内部变形。将使用完整的波形反演来得出沉积物物理特性，并将开发出故障条件的定量模型。该项目的结果将与了解全球具有相似特征的被动利润率上的潜艇滑坡动态有关。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估审查标准来通过评估来获得支持的。