GEOSTATISTICAL ANALYSIS OF THE NORTHERN SNAKE RANGE DECOLLEMENT

The Northern Snake in Eastern Nevada is a metamorphic core complex (MCC) in the extended Basin and Range province in western North America. Here, a classic MCC is well developed, consisting of; 1) normal faulted upper plate rocks exhibiting brittle behavior, transitioning into 2) mylonitic rocks of the metamorphic lower plate exhibiting ductile behavior. The boundary between the two plates consists of a low angle detachment fault, or decollement. The decollement is usually thought to represent the brittle-ductile transition at depths of 10-12 km. The decollement serves a large scale structural boundary in the North Snake Range. In order to more fully understand the decollement and its role in MCC development, we use a GIS and geostatistical techniques to analyze the geometry of a part of the decollement in the Northern Snake Range. The GIS allowed us to gather and organize large amounts of data related to the decollement. First, we overlaid digital elevation models (DEM’s) with the geological data in order to extract elevation points along the decollement. Using various geostatistical techniques, we use known elevation points to interpolate elevation points where the decollement has been eroded through. With the interpolated surface, we can analyze the decollement for any trends in its structure and shape. Future study of other MCC's in the Basin and Range can be compared to the information we find in the North Snake Range to better understand their structural development.