A seismic and gravity survey along the eastern front of the Sierra Nevada, California, between southern Owens Valley and the Garlock fault, outlines a series of basins with maximum depths ranging from 5,000 to 9,000 ft. These basins follow the front of the Sierra Nevada in a continuous chain with one interruption of about 10 miles near Little Lake. The gravity anomalies indicate that the basins...

We demonstrate that observed contrasts of upper crustal structures across large continental strike-slip faults are sufficient to produce artificial vertical Moho offsets of several kilometers in studies using laterally homogenous models. This can have significant impact on efforts to understand how the observed surface displacement is accommodated in the deep crust. An existing hypothesis that ...

[1] A compilation of the apatite and zircon fission track ages of the Alpine chain points to markedly different patterns of cooling and exhumation of the Eastern Alps compared to the central andWestern Alps. The site of exhumation and shortening in the Western Alps migrated outward, whereas it was more stationary in the Eastern Alps, where it created a narrower metamorphic belt. A correlation o...

During Leg 185 two deep-water sites will be drilled, one seaward of the Mariana Trench (Ocean Drilling Program Hole 801C) and one seaward of the Izu-Bonin Trench (Site BON8A). The primary objectives are to investigate sediment subduction along this arc-trench system and to characterize the chemical fluxes during alteration of the oceanic crust. Despite the simple setting and shared subducting p...

Carbon can be a major constituent of crustal and mantle fluids, occurring both as dissolved ionic species (e.g., carbonate ions or organic acids) and molecular species (e.g., CO2, CO, CH4, and more complex organic compounds). The chemistry of dissolved carbon changes dramatically with pressure (P) and temperature (T). In aqueous fluids at low P and T, molecular carbon gas species such as CO2 an...

Fifteen North Cascade Arc basalts and andesites were analyzed for Mg isotopes to investigate the extent and manner of crustal contributions to this magmatic system. The δ 26Mg of these samples vary from within the range of ocean island basalts (the lightest being −0.33 ± 0.07‰) to heavier compositions (as heavy as −0.15 ± 0.06‰). The observed range in chemical and isotopic composition is simila...

9 Shear zones channelize fluid flow in the Earth’s crust. However, little is known about 10 deep crustal fluid migration and how fluids are channelized and distributed in a deforming lower 11 crustal shear zone. This study investigates the deformation mechanisms, fluid-rock interaction 12 and development of porosity in a monzonite ultramylonite from Lofoten, northern Norway. The 13 rock was def...

Wave propagation in heterogeneous media is not only characterized by reflection, transmission and conversion of seismic energy but also by effects such as scattering and tunneling and can be observed on many scales. We investigate elastic wave propagation in the lower crust of the earth. It is remarkable that distance and time scales in a deep crustal reflection problem can be easily transforme...

Detection of deep and hidden mineralization using the surface geochemical data is a challenging subject in the mineral exploration. In this work, a novel scenario based on the spectrum–area fractal analysis (SAFA) and the principal component analysis (PCA) has been applied to distinguish and delineate the blind and deep Mo anomaly in the Dalli Cu–Au porphyry mineralization area. The Dalli miner...