Search

Your search keyword '"Connor, Charles B."' showing total 21 results
Start Over Author "Connor, Charles B." Search Limiters Full Text
21 results on '"Connor, Charles B."'

11. Risk Analysis

Author

Austin, John H., Connor, Charles B., and Hill, Brittain E.

Published
1997

14. Is uplift of volcano clusters in the Tohoku Volcanic Arc, Japan, driven by magma accumulation in hot zones?: A geodynamic modeling study

Author

George, Ophelia, Malservisi, Rocco, Govers, R.M.A., Connor, Charles B., Connor, Laura J., and Tectonophysics

Abstract

In many volcanic arcs, the rate of tectonic uplift cannot be explained by lithospheric plate motion alone but may be associated with dynamic uplift. Buoyant forces associated with underplated magma bodies lift the upper crust and leads to relatively high rates of topographic change. One such region is northern Honshu, Japan, where Quaternary volcano clusters are spatially associated with uplifted crust and isostatic gravity anomalies. Axisymmetric inversion of Bouguer gravity data for the Sengan volcano cluster shows that these gravity anomalies can be modeled by 30 km radius bodies emplaced at ∼15 km depth. Axisymmetric, finite element models, generated using GTECTON, of a layered Earth representative of the Tohoku crust indicate that the deformation of these midcrustal intrusions produces elevated topography on the surface directly above the intrusion that is bounded by a shallow peripheral trough. The wavelengths of vertical deformation produced by these bodies are sensitive to the thickness of the models' elastic layer and relatively insensitive to the models' rheology. This suggests that the amplitude of the vertical deformation represents a trade-off between the size of the intrusion and the thickness of the elastic layer and is less strongly influenced by the rheology of the lithosphere into which the bodies are emplaced. Our results are consistent with hot zone and hot finger models for the arc and indicate that Tohoku Volcanic Arc features such as gravity anomalies and uplifted basement are related to crustal magma intrusions and hot zones rather than directly related to mantle processes.

Published
2016

21. Relationship between dike and volcanic conduit distribution in a highly eroded monogenetic volcanic fi eld: San Rafael, Utah, USA.

Author

Kiyosugi, Koji, Connor, Charles B., Wetmore, Paul H., Ferwerda, Brian P., Germa, Aurélie M., Connor, Laura J., and Hintz, Amanda R.

Subjects
*GEOLOGICAL mapping, *AQUEDUCTS, *DIKES (Geology), *VOLCANIC fields, *VOLCANIC hazard analysis, *GEOLOGICAL statistics
Abstract

We mapped 63 conduits, ~2000 dike segments, and 12 sills in the San Rafael subvolcanic field, Utah (United States), where this Pliocene magmatic system is eroded to a depth of ~0.8 km and is exceptionally well exposed. Although the number of mapped conduits, dikes, and sills might represent minimums, depending on the level of erosion and exposure, mapped dikes are more numerous around the areally extensive sills and interact with sills and conduits in complex ways. We analyze conduit distribution using kernel density methods and compare results with dike and sill distribution. We find that the distribution of conduits matches the major features of dike distribution, including development of clusters and distribution of outliers. These statistical models are then applied to the distributions of volcanoes in several recently active volcanic fields, where intrusion distributions must be inferred from very sparse data, and compared with San Rafael conduit distribution. This comparison supports the use of statistical models in probabilistic hazard assessment for distributed volcanism. Specifically, renewed dike intrusion and potential eruptions in active basaltic systems can be assessed probabilistically from the distribution of older volcanoes in distributed volcanic systems. [ABSTRACT FROM AUTHOR]

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results