Integrated geophysical study of the Klamath Mountains, northern California and southwest Oregon

Enrique Casana, University of Texas at El Paso


The Klamath Mountains make-up a fundamental tectonic element of the North American Cordillera. They form the largest exposure of pre-Tertiary rocks between the Sierra Nevada and North Cascades (Snoke and Barnes, 2006); in addition, their importance as an area of study is enhanced by the fact that they provide the type example of accretion by thrust faulting of terrane slices (Irwin, 1960; 1981). This region has been studied in detail in the past and out of these investigations has come an immense amount of geologic information. However, new tools and information exist that will allow us to identify the geometry and the extent of the many geologic units within the province, as well as the spatial extent of faulting in the Western edge of the North American Continent. This study integrates the analysis of gravity, magnetic, seismic and remote sensing data of the Klamath Mountains province (KMp) to advance our understanding of the Mesozoic accretionary processes that led to the formation of a major portion of the North American continental lithosphere. Large gravity and aeromagnetic data sets were acquired and processed resulting in data grids that identify two large, low-gravity regions within the area. One low underlies the Klamath terranes, and a second one, roughly the same size, lies a short distance to the northeast. Further analysis of these two features lead to the conclusion that the first anomaly is related to compensation at depth of the high density materials that make-up the KMP, while the second gravity trough is related to a large north-trending graben structure and the low density materials within it. The end-product of this study is a set of five density models of areas within the study area. In general, these models do a good job at incorporating all the different data sets and producing reliable, large scale cross-sections of the area.* ^ *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation).^

Subject Area


Recommended Citation

Casana, Enrique, "Integrated geophysical study of the Klamath Mountains, northern California and southwest Oregon" (2007). ETD Collection for University of Texas, El Paso. AAI1445688.