We have modified the kinetic equations for the absorption of hydrogen in transition metals to include the effects of strong subsurface bonding. The new equations show that the subsurface, self-trapped hydrogen acts as a valve for the admission of hydrogen into the bulk. The explanation for a number of experimental facts, not well understood before, neatly follows. Discrepancies between theory a...

Wave-equation migration with the velocity of the primaries maps non-diffracted waterbottom multiples to an hyperbola in subsurface-offset-domain-common-image-gathers. Furthermore, for positive surface offsets, the multiples are mapped to non-positive subsurface offsets if sediment velocity is faster than water. The larger the offset in the data space, the larger the subsurface offset and the sh...

[1] Previous studies have tested the long‐term coupling between air and terrestrial subsurface temperatures working under the assumption that linear trends in surface air temperature should be equal to those measured at depth within the subsurface. A one‐ dimensional model of heat conduction is used to show that surface trends are attenuated as a function of depth within conductive media on tim...

Nonpoint source contamination of surface and groundwater resources with nitrate-N (NO3-N) has been linked to agriculture across the midwestern USA. A 4-yr study was conducted to assess the extent of NO3-N leaching in a central Iowa field. Water flow rate was monitored continuously and data were stored on an internal datalogger. Water samples for chemical analysis were collected weekly provided ...

magnetotelluric (mt) method is an electromagnetic technique that uses the earth natural field to map the electrical resistivity changes in subsurface structures. because of the high penetration depth of the electromagnetic fields in this method (tens of meters to tens of kilometers), the mt data is used to investigate the shallow to deep subsurface geoelectrical structures and their dimensions....

Subsurface scattering and light transport in volumetric media are critical to achieve a realistic depiction of a material. We describe several analytical approximations and methods for volumetric light transport in media of various optical properties that are efficient and easy to compute. Most natural materials exhibit a sudden surge in brightness called the opposition effect around the zero p...

Subsurface modeling from seismic and borehole data is important for reservoir prediction, geophysical exploration and production. A reasonable model should honor borehole rock properties and conform to seismic structural and stratigraphic features. Such a subsurface model can be di cult to create in cases complicated by faults and unconformities. Automatic and semi-automatic methods have been p...

A corrosive environment leaves in-service conductive structures prone to subsurface corrosion which poses a severe threat to the structural integrity. It is indispensable to detect and quantitatively evaluate subsurface corrosion via non-destructive evaluation techniques. Although the gradient-field pulsed eddy current technique (GPEC) has been found to be superior in the evaluation of corrosio...

[1] In this paper for the first time I show that themultidecadal variations of observed tropical North Atlantic (TNA) sea surface temperature (SST) are strongly anticorrelated with those of the observedTNA subsurface ocean temperature, with long-term trends removed. I further show that the anticorrelated change between the TNA surface and subsurface temperature is a distinctive signature of the...

[1] Scale and slope dependence of hydrologic response are investigated for two channel network source areas (unchanneled valleys) in the Oregon Coast Range. Observations of response to both natural and applied precipitation reveal that runoff occurred as subsurface flow in which water passed through partially saturated soil, into the shallow fractured bedrock, to emerge as subsurface partial so...