Overpressure and Fluid Flow in New Jersey Continental Slope: Implications for Slope Stability and Cold Seeps

新泽西大陆斜坡的超压和流体流动：对斜坡稳定性和冷渗的影响

• 批准号: 0003467
• 负责人: Peter Flemings
• 金额: $ 10.8万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2003-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0003467&HistoricalAwards=false
• 关键词: Overpressure; Fluid; Flow; New; Jersey

Overpressure and Fluid Flow in New Jersey Continental Slope: Implications for Slope Stability and Cold SeepsPrincipal Investigator: Peter B. FlemingsObservations, theory, and experiments will be used to characterize the temporal and spatial evolution of fluid pressure and stress on the continental slope, offshore New Jersey. PI will image the porosity of the slope sediments using core data, well logs, and seismic velocities. Fluid pressures will be predicted using a porosity-effective stress relationship. This approach will provide a regional map of the porosity and fluid pressures. Greg Mountain (Lamont-Doherty Earth Observatory) will aid them in correlating the pressure distribution to key Miocene-to-present stratigraphic surfaces. Fluid pressures will also be correlated with exposed submarine canyons to evaluate the impact high pressures have on slope stability. A numerical model that couples consolidation theory and groundwater mechanics will simulate the porosity and pressure evolution. Porewater geochemical data will be used in concert with porosity data to validate the flow model. PI will perform laboratory experiments, at ExxonMobil Upstream Research Company, on samples from ODP Site 1073 to determine the compressibility and permeability of slope sediments. The experiments will also provide fluid pressure estimates that can be compared to the pressures predicted from porosity and those simulated in the flow models. After constraining the fluid pressures, their origins, and their distribution, we will evaluate the stress evolution, which is intimately tied to the fluid pressures and to slope stability.The proposed research will provide quantitative insights into how hydrodynamics and state of stress are linked on rapidly deposited margins. This local study has broad application to a variety of geological settings and societal problems. The study has the potential to estimate the location of sea floor seeps and the volume of fluids they expel; fluid flux relates to the size and diversity of biotic communities that use nutrients supplied by seep fluids. The pressure-stress field is important to understand for subsurface exploration and to evaluate slope stability. A definitive understanding of the origin of pressures and the focussed flows they can generate will be easily exportable to industry. The coupling of fluid pressure and stress will define the role excess fluid pressures play in sculpting continental slopes and may serve as a way to evaluate potential submarine landslide hazards.

新泽西州陆坡的超压和流体流动：对斜坡稳定性和冷泉的影响主要研究员：Peter B.Flemings将利用观测、理论和实验来描述新泽西州近海大陆斜坡上流体压力和应力的时空演变。PI将使用岩心数据、测井和地震速度来成像斜坡沉积物的孔隙度。流体压力将使用孔隙度-有效应力关系进行预测。这种方法将提供孔隙度和流体压力的区域图。Greg Mountain(Lamont-Doherty地球观测站)将帮助他们将压力分布与关键的中新世到现在的地层面进行关联。流体压力也将与裸露的海底峡谷相关联，以评估高压对斜坡稳定性的影响。将固结理论和地下水力学相结合的数值模型将模拟孔隙度和压力的演化。孔隙水地球化学数据将与孔隙度数据配合使用，以验证流动模型。PI将在埃克森美孚上游研究公司对来自ODP1073站点的样品进行实验室实验，以确定斜坡沉积物的可压缩性和渗透性。这些实验还将提供流体压力估计，可以与根据孔隙度预测的压力和流动模型中模拟的压力进行比较。在约束了流体压力及其来源和分布之后，我们将评估与流体压力和斜坡稳定性密切相关的应力演化。拟议的研究将提供关于快速沉积边缘上流体动力学和应力状态如何联系的定量见解。这项地方性研究对各种地质背景和社会问题都有广泛的应用。这项研究有可能估计海底渗漏的位置和它们排出的流体的数量；流体流量与使用渗漏流体提供的营养的生物群落的大小和多样性有关。压力应力场对于地下勘探和评价边坡稳定性具有重要意义。对压力的来源及其可能产生的集中流动的明确理解，将很容易输出到工业中。流体压力和应力的耦合将确定过量流体压力在塑造大陆斜坡中所起的作用，并可能作为评估潜在海底滑坡危险的一种方法。