Geologic Investigation of the Lewis Thrust System, Glacier National Park, Montana

刘易斯逆冲断层是加拿大落基山脉南部晚白垩世至早第三纪发育的主要构造单元之一，经常被引用为解释逆冲几何学和运动学的经典例子。美国地质勘探局为更新冰川国家公园地质而发起的测绘工作因预算限制而提前结束，然而，相当复杂的结构的发现为这项研究提供了基础。将通过构造填图和随后的运动学标志研究，研究无序逆冲作用形成的双重断裂带的可能性。结果将允许准确记录刘易斯系统断层之间的几何关系，导致对这一重大推力的重要例子的历史进行全面重新评估。

The Lewis thrust fault is one of the major tectonic elements developed during late Cretaceous to early Tertiary time in the southern Canadian Rocky Mountains, and is often cited as a classic example to illustrate thrust geometry and kinematics. Mapping initiated by USGS to update the geology of Glacier National Park prematurely ended due to budget constraints, however, the discovery of considerable structural complexity provided the basis for this research. Possible development of a duplex fault zone developed by out-of-sequence thrusting will be investigated by structural mapping, and subsequent study of kinematic indicators. Results will allow accurate documentation of geometric relationships between the faults of the Lewis system leading to a full re-evaluation of the history of this important example of a major thrust.