Displacement History of the Chugach-Prince William Terrane

楚加奇王子威廉·泰拉尼的位移历史

• 批准号: 9118170
• 负责人: Michael McWilliams
• 金额: $ 6.72万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-01-15 至 1993-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9118170&HistoricalAwards=false
• 关键词: Displacement; History; Chugach; Prince; William

A strong discordance exists between displacement estimates for Cordilleran tectonic terranes inferred from paleomagnetic studies as opposed to geologic studies. Existing paleomagnetic data from southern Alaska suggest large northward displacements of the Chugach-Prince William (CPW) terrane with respect to the southern Alaska terrane since the lower Tertiary, but geologic evidence suggests the two terranes were juxtaposed in early Tertiary time. However, the paleomagnetic data base for the CPW terrane is small and highly variable and may therefore be unreliable. This study will resolve the discrepancy by detailed paleomagnetic analysis of a suite of ophiolitic and dike rocks already obtained from the Kenai Peninsula and Knight-Island. The results will clarify the tectonic evolution of the northern Cordillera, particularly the Alaskan segment, and will have bearing on orogen-parallel displacement estimates for accreted terranes in other orogenic belts.

从古地磁研究中推断的科迪勒构造地体的位移估计与从地质学研究中推断的结果之间存在着强烈的不一致。阿拉斯加南部现有的古地磁数据表明，自下第三纪以来，楚加赫-威廉王子(CPW)地体相对于阿拉斯加南部地体发生了较大的向北位移，但地质证据表明，这两个地体在早第三纪并置。然而，CPW地体的古地磁数据库很小，变化很大，因此可能不可靠。这项研究将通过对已从基奈半岛和奈特岛获得的一套蛇绿岩和脉岩进行详细的古地磁分析来解决这一差异。这一结果将阐明科迪勒拉北部，特别是阿拉斯加段的构造演化，并将对其他造山带中造山带增生地体的造山带平行位移估计产生影响。