No abstract

The present study attempts to delineate different groundwater potential units using remote sensing and geographic information system (GIS) in Khallikote block of Ganjam disrict, Orissa. Thematic maps of geology, geomorphology, land use and land cover, drainage density, lineament density, slope and DEM (digital elevation model) were prepared using the Landsat Thematic Mapper data in 3 spectral bands, band 7 (mid-infrared light), band 4 (near-infrared light), Band 2 (visible green light). Relationship of each layer to the groundwater regime has been evaluated through detailed analysis of the individual hydrological parameters. The SMCE (Spatial MultiCriteria Evaluation) module in ILWIS (Integrated Land and Water Information System) supports the decision-making process for evaluating the ground water potential zones in the area. The study shows that more than 70% of the block is covered by medium to excellent category having good ground water potential.

No abstract

Selenium is an essential trace element in human diet with carcinogenic effect when consumed in excess. This paper examines the depthwise variartion of selenium in the aquifers of northeastern Punjab (India) in the Indo-Gangetic Plains in a piedmont zone. Out of 210 km2 hydrogeologically studied area in parts of Hoshiarpur and Nawanshahr districts of Punjab State, about 50% of area was found affected by high selenium concentration problem in groundwater. Three aquifer groups were identified, i.e., aquifer group I, II and III with depth ranges of about 75-95 m (thickness ~90 m), 120-230 m (thickness ~110 m) and beyond 255 m, respectively. A clay horizon of about 15-35 m thickness separates aquifer group of I and II and that of about 15-30 m thickness aquifer group of II and III. Aquifer group I is unconfined, aquifer group II is semi-confined and aquifer group III is confined in nature. High concentrations of selenium is observed in aquifer groups I and II with concentrations decreasing with depth. Aquifer group III is devoid of selenium. The symptoms of high contents of selenium started emerging when people deepened their wells in the 1970s to a depth of 20-45 m in a sandy clay horizon. This, however, is yet to be verified and warrants further investigation.