Jura-Cretaceous Back-Arc Basin Evolution and Collisional Tectonics of West-Central British Columbia

英国中西部Skeena群的盆地分析 哥伦比亚号将用于评估早白垩世构造 和碰撞力学。 要测试的模型是， 最初的碰撞导致了两个 晚侏罗世至早侏罗世的俯冲带和隆升 白垩纪斯基纳拱。渐进碰撞导致扩张 在西边一个活跃的弧形后面 拱门下陷了 在早白垩世和Skeena群沉积在 弧后盆地 本研究将解决的两个假设 弧后沉降是拉张作用的结果， （2）沉降是由于缩短，构造变形， 载荷和岩石圈挠曲。 区分标准将 包括沉积物物源、相分析、沉降史 古水流分析、成岩历史和微量元素 层间火山岩地球化学 本研究结果 将对侏罗纪的进化产生重要影响 白垩纪太平洋盆地和法拉隆板块。

A basin analysis of the Skeena group of west-central British Columbia will be undertaken to evaluate Early Cretaceous tectonics and mechanics of terrane collision. The model to be tested is that initial terrane collision resulted in the mergence of two subduction zones and uplift of the Late Jurassic to earlier Cretaceous Skeena Arch. Progressive collision led to the expansion of the arch behind an active arc to the west. The arch subsided in the Early Cretaceous and the Skeena Group were deposited in the back-arc basin. The two hypotheses that this study will address are (1) back arc subsidence was the result of extension or transtension, or (2) subsidence was due to shortening, tectonic loading and lithospheric flexure. Distinguishing criteria will include sediment provenance, facies analysis, subsidence history, paleocurrent analysis, diagenetic history, and trace element geochemistry of interbedded volcanics. The results of this study will have important implications for the evolution of the Jurassic- Cretaceous Pacific basin and the Farallon plate.