Displacement History of the Chugach-Prince William Terrane

根据古地磁研究推断的科迪勒拉构造地体的位移估计与地质研究推断的位移估计存在很大的不一致。来自阿拉斯加南部的现有古地磁资料表明，自下第三纪以来，Chugach-Prince William （CPW）地体相对于阿拉斯加南部地体有较大的北移，但地质证据表明，这两个地体在早第三纪并置。然而，CPW地块的古地磁数据库很小且变化很大，因此可能不可靠。这项研究将通过对已经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。研究结果将澄清北科迪勒拉的构造演化，特别是阿拉斯加段，并将对其他造山带的造山带平行位移估计产生影响。

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.