Stratigraphic and Tectonic Analysis of Neogene Coal-Bearing Basins Along the Alaska Range Suture Zone

阿拉斯加山脉缝合带新近纪含煤盆地地层与构造分析

• 批准号: 9725587
• 负责人: Kenneth Ridgway
• 金额: $ 13.31万
• 依托单位: Purdue Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2002-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9725587&HistoricalAwards=false
• 关键词: Stratigraphic; Tectonic; Analysis; Neogene; Coal

9725587 Ridgway This proposal seeks funding for a three-year investigation of Neogene sedimentary basins located along the north-central flank of the Alaska Range. These basins contain the record of basin development along an ancient suture zone, the uplift history of the highest mountain range in North America, extensive low-sulfur coal reserves, and potential petroleum reservoirs. The east-west trending basins were filled by fluvial and lacustrine deposits and consist of the Miocene Usibelli Group (~ 600 m thick) and the Pliocene Nenana Gravel (~ 1000 m thick). The general questions to be addressed include: (1) How do basins form within the interior of collisional/accretionary orogenic settings? Can a conceptual model be developed for basin formation along former suture zones? (2) What can the synorogenic deposits contained within these basins teach us about the Neogene uplift of the Alaska Range? Does the detrital record contain information on how deformation and uplift changed along strike and through time for this orogenic belt? What was the influence of paleoclimate on detrital composition during unroofing of the Alaska Range? (3) Coal from the Usibelli Group is becoming an increasingly important energy source for Alaska and for export to Pacific Rim countries. What were the depositional, tectonic, and climatic controls on coal deposition in these basins? A regionally integrated stratigraphic, paleogeographic and tectonic framework for all the Neogene basins will be needed to answer these questions. A database will be established by reconstructing the depositional systems for each basin; construction of a series of cross sections through the central Alaska Range; and compositional analysis of sandstone's and conglomerates. Major contributions of the proposed research include documentation of the long term evolution of sedimentary basins along a suture zone; delineation of along strike variations in the uplift history of the Alaska Range; and analysis of the distribution of potentially commercial coals for future exploration.

9725587 Ridgway 该提案寻求资助对位于阿拉斯加山脉中北部侧翼的新近纪沉积盆地进行为期三年的调查。 这些盆地包含沿古代缝合带盆地发育的记录、北美最高山脉的隆升历史、广泛的低硫煤储量和潜在的石油储层。 东西走向的盆地充满了河流和湖泊沉积物，由中新世乌斯贝利群（约 600 m 厚）和上新世 Nenana 砾石（约 1000 m 厚）组成。 要解决的一般问题包括：（1）碰撞/增生造山环境内部如何形成盆地？ 能否为沿前缝合带形成盆地建立一个概念模型？ (2) 这些盆地内的同造岩沉积物可以告诉我们关于阿拉斯加山脉新近纪隆起的什么信息？ 碎屑记录是否包含该造山带变形和隆起如何沿着走向和时间变化的信息？ 在阿拉斯加山脉屋顶剥落过程中，古气候对碎屑成分有何影响？ (3) 乌斯贝利集团的煤炭正成为阿拉斯加以及向环太平洋国家出口的日益重要的能源来源。 这些盆地中煤炭沉积的沉积、构造和气候控制因素是什么？ 回答这些问题需要一个针对所有新近纪盆地的区域综合地层、古地理和构造框架。 通过重建每个盆地的沉积系统来建立数据库；建造一系列穿过阿拉斯加山脉中部的横截面；以及砂岩和砾岩的成分分析。 拟议研究的主要贡献包括记录沿缝合带沉积盆地的长期演化；描绘阿拉斯加山脉隆起历史中的沿走向变化；并分析未来勘探的潜在商业煤炭的分布。