Laboratory simulations and field studies of the shallow subsurface have shown that microbes and their extracellular products can influence the mobility of toxic metals from waste disposal sites. Modelling the transport of contaminants in groundwater may, therefore, require the input of microbial ecology data in addition to geochemical data, thus increasing the costs and the uncertainty of predi...

The primary research goal is to develop techniques to determine subsurface turbulence from remote measurements using infrared imaging of the skin layer. We aim to infer flow rate, turbulence intensity and subsurface-generated turbulent structures from surface temperature patterns. We will take advantage of the two complementary indicators of subsurface flow provided by IR imagery: the thermal s...

Siyi Shao). Upper right: Carbonate minerals (white) filling fractures formed from mechanical response to chemical reactions in olivine-rich rocks (Courtesy of Peter Kelemen). Lower Right: Localized geochemical alteration of rock matrix due to fluid flow and reactions along fractures (Source of image unknown). Executive Summary From beneath the surface of the earth, we currently obtain about 80-...

Many air-breathing aquatic foragers may be killed by aerial or subsurface predators while recovering oxygen at the surface; yet the influence of predation risk on time allocation during dive cycles is little known in spite of numerous studies on optimal diving. We modeled diving behavior under the risk of predation at the surface. The relationship between time spent at the surface and the risk ...

We present a detailed theoretical analysis and experimental results on a subsurface microscopy technique that significantly improves the light-gathering, resolving, and magnifying power of a conventional optical microscope. The numerical aperture increasing lens sNAILd is a plano-convex lens placed on the planar surface of an object to enhance the amount of light coupled from subsurface structu...

The search for evidence of past or present life on Mars is the principal objective of the 2020 ESA-Roscosmos ExoMars Rover mission. If such evidence is to be found anywhere, it will most likely be in the subsurface, where organic molecules are shielded from the destructive effects of ionizing radiation and atmospheric oxidants. For this reason, the ExoMars Rover mission has been optimized to in...

[1] Ground-penetrating radar (GPR) has the potential to image the Martian subsurface to give geological context to drilling targets, investigate stratigraphy, and locate subsurface water. GPR depth of penetration depends strongly on the electromagnetic (EM) properties (complex dielectric permittivity, complex magnetic permeability, and DC resistivity) of the subsurface. These EM properties in t...

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 difficult to build in cases complicated by faults and unconformities. Automatic and semiautomatic methods have been ...

This study was designed to evaluate the improved version of the Root Zone Water Quality Model (RZWQM) using 6 yr (1992-1997) of field-measured data from a field within Walnut Creek watershed located in central Iowa. Measured data included subsurface drainage flows, NO3-N concentrations and loads in subsurface drainage water, and corn (Zea mays L.) and soybean [Glycine mar (L.) Merr.] yields. Th...

Detailed airborne, surface, and subsurface chemical measurements, primarily obtained in May and June 2010, are used to quantify initial hydrocarbon compositions along different transport pathways (i.e., in deep subsurface plumes, in the initial surface slick, and in the atmosphere) during the Deepwater Horizon oil spill. Atmospheric measurements are consistent with a limited area of surfacing o...