Subsurface waters have been classified into meteoric water, ocean water, evolved connate water, magmatic water and juvenile water. Geothermal water is mostly meteoric and oceanic water although andesitic waters near subduction areas often contain significant proportions of evolved connate and magmatic waters. Geothermal waters have been classified with respect to their anion and cation contents...

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...

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...

The Geological Survey of the Netherlands (GSN) produces 3D stochast ic geological models of the upper 50 meters of the Dutch subsurface. The voxel models are regarded essential in answering subsurface questions on, for example, aggregate resources, groundwater flow, land subsidence studies and the planning of large-scale infrastructural works such as tunnels. GeoTOP is the most recent and detai...

A three-dimensional numerical model is proposed for modeling the TP transport in the Horizontal Subsurface Flow (HSSF) and Wavy subsurface Flow (WSSF) constructed wetland in this article. Both numerical simulations and physical experiments indicate that the removal efficiency of WSSF is higher than that of HSSF. The difference of performance in removing pollutants, e.g., Total Phosphorus (TP), ...

Isotopic tracer and temperature measurements at large volume cold springs in the central Oregon Cascades are used to understand the pattern of groundwater flow. Standard oxygen and hydrogen isotope interpretations are used to determine the mean recharge elevation for springs. Carbon and helium isotopes are used to measure the component of dissolved magmatic gas in the spring waters. Inferences ...

[1] The spatial distribution of subsurface soil textural properties across the landscape is an important control on the hydrological and ecological function of a watershed. Traditional methods of mapping soils involving subjective assignment of soil boundaries are inadequate for studies requiring a quantitative assessment of the landscape and its subsurface connectivity and storage capacity. Ge...

Conventional material removal of BK7 optical glass will normally result in brittle fracture at the surface, generating severe subsurface damage and poor surface finish. Subsurface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. However, through ductile mode grinding it is possible to reduce the surface and subsurface cracks. It is m...

Introduction: Estimates of the global inventory of water on Mars based on a determination of the amount of water required to erode the outflow channels suggest that a quantity equivalent to a global ocean 0.5 to 1 km deep may be stored in the planet’s subsurface [1, 2]. As this inventory post dates the timing of the most efficient processes that may have lead to its removal, the majority of thi...