Collaborative Research: Clinker Geochronology and Geomorphic Evolution of the Powder River Basin, Wyoming

合作研究：怀俄明州粉河盆地的熟料地质年代学和地貌演化

• 批准号: 0649425
• 负责人: Peter Reiners
• 金额: $ 11.6万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2008-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0649425&HistoricalAwards=false
• 关键词: Collaborative; Research; Clinker; Geochronology; Geomorphic

Clinker, rock metamorphosed by natural coal burning, has formed in the Powder River Basin (and other areas of the Rocky Mountains) since at least Pliocene. Clinker dominates the topographic form of many of the basins in which it is found, because it is more resistant to weathering than surrounding unaltered bedrock. It also preserves a record of the spatial-temporal patterns of fluvial incision, lateral backwasting, and plateau formation in these landscapes, because coal only burns when close to the surface, above the water table and ventilated with surface oxygen. Using (U-Th)/He ages of detrital zircons that are reset during clinker formation, we will map the patterns of coal burning and shallow exhumation in detail in several regions of the PRB in Wyoming and Montana, as well as characterize clinker ages over a broader scale throughout the basin. Model predictions of clinker age-patterns in individual drainages and across the landscape suggest that our results will be able to discriminate between at least some of these possible climatological or tectonic mechanisms driving landscape evolution. This work will form the basis of collaborative research between Reiners and Riihimaki, as well as individuals in the BLM and the Northern Cheyenne Tribe, and undergraduate students from Yale and Bryn Mawr.

熟料，自然煤燃烧变质的岩石，至少从上新世开始就在粉河盆地（和落基山脉的其他地区）形成。熟料在许多盆地的地形中占主导地位，因为它比周围未改变的基岩更耐风化。它还保存了河流切割，侧向回耗和高原形成在这些景观的时空模式的记录，因为煤只有在接近地表时才燃烧，在地下水位以上，并与地表氧气通风。使用（U-Th）/He年龄的碎屑锆石，在熟料形成过程中复位，我们将映射的煤燃烧和浅剥露的模式在几个地区的PRB在怀俄明州和蒙大拿州，以及在更广泛的范围内整个盆地的熟料年龄的特点。模型预测的熟料年龄模式在个别排水系统和整个景观表明，我们的研究结果将能够区分至少有一些可能的气候或构造机制驱动景观演变。这项工作将形成赖纳斯和Riihimaki之间的合作研究的基础，以及在BLM和北方夏延部落的个人，和耶鲁大学和布林莫尔的本科生。