Large-N Seismic Recordings at the Source Physics Experiment (SPE) Phase II Site

Date: 4/24/2019

Time: 04:00 PM

Room: Cascade I

The Source Physics Experiment (SPE) is a multi-institutional, multi-disciplinary project that consists of a series of chemical explosions conducted at the Nevada National Security Site (NNSS). The goal of SPE is to understand the complicated effect of geological structures on seismic wave propagation and source energy partitioning, develop and validate physics-based modeling, and ultimately better monitor nuclear explosions. The SPE program is multi-phase with the completion of Phase I located in hard rock (granite) in 2017 and the initiation of Phase II (DAG – Dry Alluvium Geology) located in weak rock (alluvium) in 2018. A large-N seismic array was deployed at the SPE Phase II site to image the full 3-D wavefields from multiple planned explosions. The large-N seismic array consists of 500 three-component geophones covering an area of approximately 2 x 2 km. This array started operation in December 2018 and will continue into 2019. The recordings include the DAG-2 chemical explosion (50 tons on Dec 19, 2018), earthquakes, ambient noise and a series of weight drops. In this work, we present first analysis of the data recorded at the DAG large-N array and compare them with predictions. We investigate how well the large-N array may improve our understanding of subsurface structure and source characteristics.

Presenting Author: Ting Chen

Authors