COLLABORATIVE RESEARCH: Sequence of Thrusting and Implications for Mechanical Models of Thrust Belts

最近发展的冲断带模型要求逆冲楔在断层发育过程中发生内部变形以达到并保持一个临界锥度角。虽然已知有许多机制可以实现这一目标，但该模型一直受到质疑，理由是冲断带内部缺乏广泛的内部变形和持续的屈服，并且有证据表明冲断带是以“背驮式”方式发展的。本研究旨在确定锥度保持机制是否在足够大的范围内运行，以允许楔形模型发挥作用。研究人员将对落基山脉和南阿巴拉契亚山脉的断层序列进行研究，并依次从平衡剖面中恢复断层序列，并将结果与原始剖面的正演模拟预测结果进行比较。结果有望建立楔形模型在推力板就位中的可行性。

A recently developed model for thrust belts requires that the thrust wedge deform internally to attain and maintain a critical taper angle during fault development. Although a number of mechanisms are known that would accomplish this, the model has been questioned on the grounds that there is a lack of extensive internal deformation and continuous yielding within thrust belts and that there is evidence that thrusts develop in piggy-back fashion. This study seeks to determine if taper angle-maintaining mechanisms operate in sufficient magnitude to allow the wedge model to function. Fault sequences in both the Rocky Mountains and the southern Appalachians will be studied and sequentially restored from balanced cross-sections and results compared to products predicted from forward modeling with the original section. Results are expected to establish the viability of the wedge model for thrust sheet emplacement.