Color observations from the High Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter reveal zones of localized fluid alteration (cementation and bleaching) along joints within layered deposits in western Candor Chasma, Mars. This fluid alteration occurred within the subsurface in the geologic past and has been exposed at the surface through subsequent erosion. These f...

Humans are exposed to chemicals in contaminated groundwaters that are used as sources of drinking water. Chemicals contaminate groundwater resources as a result of waste disposal methods for toxic chemicals, overuse of agricultural chemicals, and leakage of chemicals into the subsurface from buried tanks used to hold fluid chemicals and fuels. In the process, both the solid portions of the subs...

A next challenge in planetary exploration involves probing the subsurface to understand composition, to search for volatiles like water ice, or to seek evidence of life. The Mars rover missions have scraped the surface of Mars and cored rocks to make ground breaking discoveries. Many believe that the chance of finding evidence of life is expected to increase by going deeper. Deploying a system ...

Controlled Source Electromagnetic (CSEM) is an important technique in hydrocarbon exploration, because it uses the large contrast in electrical resistivity to distinguishes between water and hydrocarbons. In a shallow sea environment, the airwave that is refracted from the air-water interface dominates the recorded signal at large offsets. Therefore, the hydrocarbon detection ability of the CSE...

Volatile organic compounds (VOC) are present at over two-thirds of Superfund, Resource Conservation and Recovery Act of 1976 (RCRA), and U.S. Department of Defense sites (EPA 1996). Thus, remediation of VOCs is a top concern to the Environmental Protection Agency. Trichloroethylene (TCE) is a persistent VOC contaminant that infiltrates soil and ground water from improper disposal of dry cleanin...

Data gathered with the Dynamic Albedo of Neutron (DAN) instrument onboard rover Curiosity were analyzed for variations in subsurface neutron flux and tested for possible correlation with local geological context. A special DAN observation campaign was executed, in which 18 adjacent DAN active measurements were acquired every 0.75–1.0m to search for the variations of subsurface hydrogen content ...

This study was conducted to evaluate the performance of DRAINMOD /DRAINMOD-N on an experimental drainage field at Southeast Purdue Agricultural Center (SEPAC), based on the comparison between observed and predicted subsurface drain flows and nitrate-nitrogen losses via drainage. The site was under conventional drainage management, consisting of two replications of three tile drain spacings—5m, ...

The hyporheic zone of three reaches of Sycamore Creek, Arizona consisted of an average 63 cm depth of predominantly sand or fine gravel (0.5-5 mm). Sediments were highly porous (1923% interstitial space) and interstitial water volume was 3-4 times that of surface water. Spatial distribution of temperature, sediment organic matter, interstitial nutrients, and subsurface oxygen indicate that phys...

Access to clean water for drinking and sanitation is a human right. Today water scarcity is a large problem and inequality in access to safe water is a striking truth. In Mozambique, the US foreign aid agency Millennium Challenge Corporation introduced the Rural Water Point Installation Program to increase access to safe water and sanitation – a step towards reducing poverty. 600 water points –...

Snowmelt in mountainous areas is an important contributor to river water fl ows in the western United States. We developed a distributed model that calculates solar radia on, canopy energy balance, surface energy balance, snow pack dynamics, soil water fl ow, snow–soil–bedrock heat exchange, soil water freezing, and lateral surface and subsurface water fl ow. The model was applied to describe r...