Sequence stratigraphy and facies architecture of fluvio-deltaic depositional systems

河三角洲沉积体系层序地层与相结构

• 批准号: RGPIN-2014-05780
• 负责人: Bhattacharya, Janok
• 金额: $ 2.19万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=645410
• 关键词: Sequence; stratigraphy; facies; architecture; fluvio

The proposed research program is focused on investigating the sequence stratigraphy and 3D facies architecture of shallow marine, paralic, and fluvial depositional systems. The primary focus is on Cretaceous sedimentary sequences in the Western Interior Seaway of North America. Detailed field and subsurface studies are designed to answer questions about the larger-scale stratigraphic controls on sedimentary basin fills (e.g. eustasy versus tectonics), and equally important questions relating to the formative processes of smaller-scale sedimentary units (e.g. bedforms and bars). **High-resolution outcrop and subsurface stratigraphic analysis, integrated with chronometric and biostratigraphic control, enable the elucidation of the nature and degree of cyclicity in a global Greenhouse. There is evidence of climate-driven Milankovitch-scale cyclicity, suggesting that the Cretaceous was not an ice-free time, as has been hypothesized by some. Comparison of time-stratigraphic analysis within multiple sedimentary basins, including largely completed studies in Utah, Wyoming, and Alberta, with newly proposed analysis of intervening basins in New Mexico, Montana, and the NWT, can help unravel the relative control of tectonic versus eustatic processes, which remains an area of controversy. The research is also focused in quantifying source-to-sink relationships, and in particular using information from the depositional system (especially provenance and paleodischarge studies of the fossilized trunk rivers) to make inferences about paleo-drainage basin size and relief, connectivity of drainage systems within mountain belts, paleoclimate, and plate-tectonic reconstructions.**At the smaller-scale, the research is focused on elucidating the fundamental architectural elements and event-processes that build the sedimentary record of deltaic and shelf sedimentary systems. Facies architectural element analysis is now quite mature in the examination of aeolian, fluvial, and deep-water sedimentary systems, but is not as well documented for paralic and shallow-marine systems. Recent results from my research program have demonstrated that many of the mouth-bars, described in previous studies, are actually composite features. We have discovered the fundamental "unit" bars that scale to the formative physical processes of decelerating river-mouth plumes. This work, however, is preliminary and requires other examples as well as integration with fluid-flow modeling, numerical modeling, and integration with studies of modern systems to present a synthesis of the physical processes and time scales over which deltaic shorelines grow and decay. This is significant, not only for predicting how coastlines evolve in the face of global change, but the 3D stratigraphic organization of sediment bodies is also of fundamental importance to the characterization and modeling of analog reservoirs, such as are common in oil and gas deposits both in Canada and globally.

拟议的研究计划的重点是研究浅海，副层和河流沉积系统的序列地层和3D相结构。主要重点是北美西部内部海道的白垩纪沉积序列。详细的领域和地下研究旨在回答有关沉积盆地填充物（例如Eustasy与构造学）的较大规模地层控制的问题，以及与较小规模沉积单位的形成过程有关的同样重要的问题（例如，床形和酒吧）。 **高分辨率露头和地下地层分析，与等级和生物地层控制集成在一起，使全球温室中的循环性质和程度阐明了。有证据表明，气候驱动的米兰科维奇尺度循环性，表明白垩纪不是一个无冰的时间，正如某些人所假设的那样。在多个沉积盆地内的时间间隔分析的比较，包括在犹他州，怀俄明州和艾伯塔省的大部分完成的研究，以及对新墨西哥州，蒙大拿州和NWT的介入盆地的新提议分析，可以帮助揭示构造与eusticatic过程的相对控制，而构造和eustatic过程仍然是一个有争议的领域。这项研究还集中在量化来源之间的关系上，尤其是使用沉积系统中的信息（尤其是对化石树干河流的出处和古培养业研究），以推断有关古流域大小和浮雕的大小和浮雕，山地腰带，古气流，古层，古构造的基金会的山地质量。建立三角洲和货架沉积系统沉积记录的建筑元素和事件处理。现在，在检查风格，河流和深水沉积系统中，相当成熟，但对于寄生虫和浅层盐系统而言，相当有充分的文献记载。我的研究计划的最新结果表明，以前的研究中描述的许多口腔实际上是复合特征。我们已经发现了基本的“单位”条，该条尺寸为减速河羽的形成性物理过程。但是，这项工作是初步的，需要其他例子，并与流体流建模，数值建模以及与现代系统的研究集成，以呈现出三角洲海岸线生长和衰减的物理过程和时间尺度的综合。这是重要的，不仅对于预测海岸线面对全球变化的发展方式，而且沉积物体的3D地层组织对模拟储层的表征和建模也至关重要，例如在加拿大和全球的石油和天然气沉积中常见。