Southern Sierra Nevada continental dynamics project. Final technical report

摘要

The main objective of this study was to determine whether or not the Southern Sierra Nevada Mountain Range is supported by a crustal root. A secondary goal was to evaluate the relationship between the Sierra Nevada Range and the adjoining Death Valley extensional province. As part of the project, two seismic profiles were executed. The first was a north-south profile running from Ridgecrest to Chafant Valley. The second was an east-west profile from Death Valley to Coalinga. An NPE shot was recorded on the east-west receiver line, and the data were analyzed by forward modeling with a staggered-grid finite-difference code. Concurrently, the authors initiated an in-depth study of lower crustal and upper mantle xenoliths hosted by Neogene volcanic rocks of the central and southern Sierra Nevada region. This initial work focused on thermobarometric estimates of representative xenolith samples aimed at understanding the vertical composition of the Sierra Nevada lithosphere.