Research Frontiers in Appalachian Geology: A Pre-EARTHSCOPE (USArray) Workshop Proposal

阿巴拉契亚地质学研究前沿：EARTHSCOPE (USArray) 研讨会提案

• 批准号: 0345385
• 负责人: Akhaury Sinha
• 金额: $ 3.35万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0345385&HistoricalAwards=false
• 关键词: Research; Frontiers; Appalachian; Geology; Pre

EarthScope is the largest earth science initiative to date, designed to make new and fundamental contributions to our understanding of the 4-D evolution of continental North America. The U.S.Array component of this initiative "will dramatically improve the seismic imaging of the continental lithosphere and deeper mantle, and integrate these images to unresolved issues of continental structure, evolution and dynamics" (www.Earthscope.org). Towards this vision, it is necessary that earth science researchers begin the process of critically evaluating both the status of our current knowledge regarding the 4-D evolutionary record of continent formation, as well as formulating new questions that will provide the intellectual challenge for EarthScope. The Appalachian orogen within the continental United States provides a geologic template to explore some of the key questions concerning continental evolution .For example:How do terranes accrete? What is the structure in three dimensions of the accreting terrane and its continental infrastructure? Recognizing structural features in 3-D of deeply eroded terranes and associated suture zones will allow for a more rigorous interpretation of both modern accretionary processes, as well as helping discriminate buried suture zones common in the central United States.What is the effect of lithospheric structure and its deformation history on the development of volcanic rifted margins within the present passive margin along the eastern seaboard? Can seismic data be used effectively to image buried passive margins, foreland basins and infer basin geometry? Can new knowledge of terrane accretionary mechanisms or thrust tectonics be related to presence/absence of long lived Paleozoic depocenters? What lithospheric structure is associated with neotectonic activity in the Appalachians? A number of destructive mid-plate earthquakes have occurred in the region, and detailed imaging of the lithosphere holds the potential to answer fundamental questions about mid-plate seismicity.Can high resolution seismic data become the most critical discriminant for distinguishing the 1500Ma granite-rhyolite province of the mid-continent from the 1000 Ma Grenville province assumed to underlie the Paleozoic Appalachians? It may provide the missing link in interpreting the origin of many of the igneous/volcanic rocks of the Appalachian orogen.What are spatial and temporal scales of deformation across the continent? The Appalachian orogen has been at a plate boundary for most of its history, and the record of its deformation history/mechanisms can be recognized into the interior of North America . Developing such geologic relationships across the continent is an EarthScope vision.The workshop will provide an open forum for all earth scientists to collaboratively formulate new research opportunities within the EarthScope program, particularly those involving the natural laboratory provided by the Appalachian Mountains. Another significant objective of the workshop, in keeping with the broader goals of EarthScope, will be to initiate the process of developing synoptic databases that identify the current state of knowledge in the Appalachian orogen. Database scientists will be invited to facilitate the understanding of the research benefits of analyzing multidisciplinary data through use of information technology. The workshop will be widely advertised and open to all, but it is planned that the attendance be limited to approximately 50 individuals, including graduate students and agency representatives. This will enable timely and explicit formulation of science themes that can take advantage of EarthScope facilities, especially the US Array component. The workshop steering committee includes A.K.Sinha (Principal Investigator, Virginia Tech, [e-mail]), J.F.Read, (Virginia Tech), Art Goldstein (Colgate University) and Larry Brown (Cornell University), and will oversee the development of the workshop agenda. They will also prepare the final workshop report for publication in a national earth science society magazine, as well as for submission to NSF.The workshop format will consist of breakouts coupled with plenary sessions. Plenary sessions will present both current and bold new ideas, and will be followed by a round of breakouts. The reports from the breakout sessions will lead to a consensus set of recommendations for advancing research opportunities in the Appalachian region. These recommendations will constitute the final workshop report.

EarthScope是迄今为止最大的地球科学计划，旨在为我们理解北美大陆的4-D演变做出新的和根本性的贡献。该计划的美国阵列部分“将大大改善大陆岩石圈和更深地幔的地震成像，并将这些图像与大陆结构，演变和动力学的未解决问题相结合”（www.Earthscope.org）。为了实现这一愿景，地球科学研究人员有必要开始批判性地评估我们目前关于大陆形成的4-D进化记录的知识状况，并制定新的问题，这将为EarthScope提供智力挑战。位于美国大陆的阿巴拉契亚造山带提供了一个地质模板，可以用来探索有关大陆演化的一些关键问题，例如：岩石是如何增生的？在三维空间中，增生的火山岩及其大陆基础结构是什么？认识到在3-D的深度侵蚀的火山岩和相关的缝合带的结构特征，将允许一个更严格的解释现代增生过程，以及帮助歧视常见的埋藏缝合带在美国中部。什么是岩石圈结构的影响和它的变形历史上的火山裂谷边缘的发展，在目前的被动边缘沿着东海岸？地震数据能否有效地用于对埋藏的被动边缘、前陆盆地成像并推断盆地几何形状？新的知识的加积机制或逆冲构造是否与存在/不存在的长寿古生代沉积中心？什么样的岩石圈结构与阿巴拉契亚山脉的新构造活动有关？一些破坏性的中板块地震发生在该地区，详细的岩石圈成像有可能回答有关中板块地震活动的基本问题。高分辨率地震数据能否成为区分1500 Ma花岗岩流纹岩省的大陆中部和1000 Ma格伦维尔省假设下的古生代阿巴拉契亚山脉最关键的判别因素？它可能提供了解释阿巴拉契亚造山带的许多火成岩/火山岩的起源缺失的环节。什么是空间和时间尺度的变形在整个大陆？阿巴拉契亚造山带在其历史上的大部分时间都处于板块边界，其变形历史/机制的记录可以被识别到北美内部。在整个非洲大陆发展这样的地质关系是EarthScope的愿景。该研讨会将为所有地球科学家提供一个开放的论坛，以合作制定EarthScope计划内的新研究机会，特别是那些涉及阿巴拉契亚山脉提供的天然实验室的机会。讲习班的另一个重要目标是，根据地球观测仪的更广泛目标，启动建立天气数据库的进程，以确定阿巴拉契亚造山带的知识现状。数据库科学家将被邀请，以促进通过使用信息技术分析多学科数据的研究效益的理解。讲习班将广泛宣传，并向所有人开放，但计划出席人数限于约50人，包括研究生和机构代表。这将有助于及时和明确地制定科学主题，这些主题可以利用EarthScope的设施，特别是美国阵列组件。 研讨会指导委员会包括A.K.Sinha（弗吉尼亚理工大学首席研究员，[e-mail]）、J.F.Read（弗吉尼亚理工大学）、Art Goldstein（高露洁大学）和Larry Brown（康奈尔大学），并将监督研讨会议程的制定。他们还将准备研讨会的最终报告，以便在国家地球科学学会杂志上发表，并提交给NSF。研讨会的形式将包括分组讨论和全体会议。 全体会议将提出当前和大胆的新想法，并将随后进行一轮突破。分组会议的报告将导致一套共识的建议，以推进阿巴拉契亚地区的研究机会。这些建议将构成研讨会的最后报告。