Seismic interferometry processing is applied to an active seismic survey collected on ocean bottom seismometers (OBS) deployed at 900-m water depth over a carbonate/ hydrates mound in the Gulf of Mexico. Common midpoint processing and stacking of the extracted Green’s function gives the subsurface PP reflectivity, with a horizontal resolution of half the receiver spacing. The obtained seismic s...

Subsurface environment sensing and monitoring applications such as detection of water intrusion or a landslide, which could significantly change the physical properties of the host soil, can be accomplished using a novel concept, Wireless Signal Networks (WSiNs). The wireless signal networks take advantage of the variations of radio signal strength on the distributed underground sensor nodes of...

ground penetrating radar (gpr) method as a high resolution non-destructive geophysical method is used for detection of shallow subsurface targets. this method is based on the transmission of electromagnetic waves inside the earth and recording the reflected waves from the subsurface. as the method uses high-frequency electromagnetic waves in the frequency ranges of 12.5 to 2500 mhz (called gpr ...

Much of the row crop production agriculture in the Midwest occurs on soils developed from glacial till, but little research has addressed herbicide biodegradation in subsurface till. This study investigated the ability of indigenous microorganisms to mineralize the herbicide 2,4-D (2,4-dichlorophenoxyacetic acid) at sites in Iowa and Indiana. Microorganisms were able to mineralize 2,4-D, with r...

Excessive application of swine manure to a field over long durations can increase nitrate-nitrogen (NO 3 -N) leaching as a result of accumulation of more nutrients in the root zone than the subsequent crops may need. The objective of this study was to use the GLEAMS (V.2.1) model to compare measured versus simulated effects of swine manure application with urea-ammonium-nitrate (UAN) on subsurf...

The hydrology of vernal pools near Mather Air Force Base in Sacramento County was investigated to assess the relative importance of direct precipitation, overland flow, and subsurface flow on the water level regime of vernal pools located on a Redding-Red Bluff soil complex, and to determine if constructed pools affected the hydrology of naturallyoccurring pools. Studies included direct continu...