Geology 101 Lab Report

At noon on April 11th, 2016 my geology 101 lab class conducted a field study of two faults located on East Owens Ave (36.188378, -115.014308). The day was sunny with scattered clouds, but it had rained the day prior. These two faults are of particular importance due to their close proximity to surrounding neighborhoods. Our goal was to see how faults behave in the real world and draw conclusions on the public policy of Las Vegas concerning faults.

Outcrop #1: The first fault outcrop was a normal fault that featured three distinct layers of rock. These rocks were granite, schist, and gneiss. The schist is part of the larger Vishnu rock group. Both the layers of gneiss and schist exhibit foliation, while the layer of granite does not. This is because granite is an igneous rock, while gneiss and schist are metamorphic. The layers of rock are what allowed us to determine that the fault was indeed a fault. When looking at the fault from a distance, it was apparent that the different layers were offset from each other along the fracture in the rock, proving that there is motion between the two bodies of rock.

If the granite was as old or older than the metamorphic rocks, then it would have been metamorphosed with them. The interbedding between the granite and schist further corroborates this hypothesis, because that tells us that as the molten layer of granite pushed its way through the schist, part of the schist was melted into the granite. The gneiss present at the fault was probably a product of local metamorphism and then through time was pushed into the layers of schist. This means that the schist is the oldest layer present at outcrop one, followed by the gneiss, and finally by the