Microstructures of co-axially folded vein segments and crenulation cleavage： Evidence for dissolution phenomena in the Chamba Thrust Sheet, western Himalayas

The metasediments in the Chamba region experienced three phases of deformation: DF1, DF2 and DF3.Folded quartz veins are co-folded with the F2 crenulation folds. Their geometric and tectonic significance is studied by microstructures and shortening adjacent to the discrete crenulation cleavage, S2. Microstructures of folded vein segments, their geometric changes and truncation to cleavage (S2) are mainly due to pressure-solution phenomena and the estimated volume loss from reconstructed vein segments range from 16 to 25.5%,which is closely related to volume decrease (26%) calculated from the polydeformed slates of North Wales areas.     

Education as a determinant of fertility: a case study of Kullu Town

Using a sample of 885 females (1/2 of all married women of reproductive age), this study examines the role of education as a determinant of fertility among couples in Kullu town of Himachol Pradesh, India. Of the 885 respondents, only 149 were illiterate. The average family size was 2.88. Findings reveal that 1) the average family size was largest for illiterate respondents (3.57) and for illiterate males (3.76); 2) average family size declined consistently after the middle level of education to 1.29 for post graduate respondents and 2.33 for post graduate males; 3) a negative correlation exists between fertility and education of both husband and wife, with the wife's education having a stronger negative correlation with fertility; and 4) couples with an educational level of matriculation and above have a distinctly smaller family size than those less educated.     

Thermosolutal instability of compressible hall plasma in porous medium

The thermosolutal instability of a plasma in porous medium in the presence of a vertical magnetic field is considered to include the effects of compressibility and Hall currents. The effects of stable solute gradient and compressibility are found to be stabilizing and the Hall currents have a destabilizing effect. The system is stable for (C _p/g)<1;C _p, , andg denoting specific heat at constant pressure, uniform temperature gradient, and acceleration due to gravity, respectively. In contrast to the non-oscillatory modes in the absence of magnetic field and stable solute gradient, the presence of magnetic field (and, hence, Hall currents) and stable solute gradient introduce oscillatory modes for (C _p/g)>1. The case of overstability is also studied wherein the necessary conditions for the existence of overstability are obtained.     

Organic contaminants and characteristics of sediments from Oso Bay,south Texas,USA

The Oso Bay, Texas, sediments from nine sites were analyzed by GC-MS for organics to measure contamination in the bay. In most of the sites sediments contained tetrachloroethene (87–1433 g/kg), bis (2-ethylhexyl)phthalate (40–193 g/kg), and aliphatic hydrocarbons, C₈-C₁₃ (720–2491 g/kg). Sources of these contaminants include a landfill, military facilities, and municipal and industrial discharges. Size analysis of the sediments indicates they contain a high percentage of muddy sand (50–75 percent), which suggests that Oso Bay consists of common bay margin sediments.     

Habitat evaluation for sarus crane in the Keoladeo National Park using IRS LISS III and pan merged data and GIS

The Keoladeo National Park, Bharatpur, a man-made fresh water wetland carved out of a natural depression on the floodplain of two minor tributaries of the Yamuna-Gambhir and the Banganga is the country’s finest waterfowl habitat. This important wetland was set aside as a bird sanctuary in 1956 and it was elevated to the status of a National Park in 1981. It was also designated a Ramsar site- a wetland of international importance under the Ramsar convention. This important wetland has distinction of being the only Indian wetland to be included under both the Ramsar and the World Heritage convention. The attempt has been made to evaluate the habitat of Sarus crane in the Keoladeo National Park using satellite data — IRS LISS III and PAN merged product and GIS. Geocoded data of IRS —1C LISS III of 21 March 1999 on 1: 50,000 scale and PAN data of March 17, 1999 were used to generate the vegetation cover type map and open water. The maps showing drainage, human habitations, contours, roads, etc. were prepared using the Survey of India topographical sheets and contour map of park area. Information regarding habitat parameters was collected from the existing literature and field observations. The Sarus crane mainly fed in the wetland on the rhizome ofNymphaea sp.,Scirpus tuberosus andEleocharis plantaginea. As there were changes in their habitat requirements at different seasons, the sighting of Sarus crane in each habitat were recorded along with the time and activity during observation. The most utilized habitat for the entire period of study was moderately wet grassland followed by pools. The pools were used mainly during the summer. The water depth requirement observed was between 30–40 cm and 20–40 cm. The suitability maps for Sarus crane were then generated using all remote sensing based and conventional information using rule based equations in the GIS within the Keoladeo National Park.     

An experimental investigation of LNAPL migration in an unsaturated/saturated sand

Accidental spills of hydrocarbons, such as Light Non-Aqueous Phase Liquids (LNAPLs), are one of the most common sources of subsurface contamination. Migration of LNAPL in a porous medium is influenced by various factors such as the number of fluids present in the unsaturated/saturated zones and the proportion of pores occupied by each fluid. The results for relationship between matric suction and degree of saturation are presented in this paper for water–air, water–LNAPL and LNAPL–air systems in a sand. A simple and reliable setup using Buchner funnel was designed to obtain these relations. It was found that the relationship between matric suction head and degree of saturation is hysteretic for all the fluid systems (water–air, water–LNAPL and LNAPL–air). Furthermore, the amount of hysteresis depended upon the fluid system, with the maximum hysteresis occurring for water–air system. The results suggest that the amount of trapped air depends upon the reversal degree of saturation from drying to wetting.     

Environmental impact assessment in the Moradabad industrial area (rivers Ramganga-Ganga interfluve), Ganga Plain,India

Sediment samples collected in the Moradabad area, lying in the interfluve of the Ganga and Ramganga Rivers, were analysed for heavy metals, after studying the geomorphology of the area. Geomorphologically, the area can be divided into three terraces - the T₀, T₁ and T₂ surfaces. The rivers on these three surfaces show varying amounts of pollution depending upon the input from industries and urban settlements. The Ramganga River on the T₀ surface shows the highest amount of pollution. However, the pollution levels in all these rivers show a downstream dilution effect. The characteristic feature of the vast interfluve area (T₂ surface) is the presence of several, independent basins which are closed and rarely interact with each other or with any river. The sediments are redistributed and redeposited within the basin itself, and thus these basins serve as sinks. The sediments of one such basin in the study area show significant concentrations of arsenic, chromium, copper, nickel, lead, zinc and organic carbon. The concentrations of heavy metals in such a basin will show exponential increases with time, because there is no activity to funnel out the sediments and dilute the effect of pollution. This increase will pose more threats, as ultimately it will make its way laterally and vertically through the sediments, thereby polluting groundwater.     

Change detection in Sal forest in Dehradun Forest Division using remote sensing and geographical information system

The review of study site have revealed the change in vegetation cover of Sal Dense to Sal Medium and Sal Open in 6 forest Mosaics owing to biotic and abiotic conditions prevailing in the specific areas. Analysis carried out using thematic map derived from aerial photograph of 1976 and satellite data of IRS 1C LISS III False Colour Composite (FCC) of March 1999 revealed the cause for change in forest density classes. Deforestation, encroachment and agriculture have been identified as the underlying causes, which have affected some specific locations to a marked extent. There has been a progressive and remarkable change among vegetation classes from 1976 to 1999. It is evident from forest type and density map that Sal density has significantly reduced from Sal Dense 65.61 % in 1976 to Sal Dense 11.12% in the year 1999 followed by Sal Open 11.18 % and Sal Medium 18.24 %. The overall change has been estimated to be 42.11% of the total forested area.     

A new approach to verify the model core with idealized experiments

Summary ?A newly developed ocean general circulation model has been tested and verified with some idealized experiments. Generally two types of idealized experiments have been done here. First types are called as “symmetric experiments” and second types are called as “transport experiments”. The first types of experiment help to correct the model core and any deficiency from boundary conditions. The second types of experiment are the type of validation experiment. In both the experiments there are no continents, so in the first type of experiments where symmetric forcings are provided one can expect that model should maintain the symmetric nature. In the second type of experiments one can expect that model should respond correctly to the wind forcings, if no wind curl is present in the wind forcing there will be no circulation in the extratropics and if there is no wind the equator there will be no circulation. The model reproduces the possible envisaged results of these experiments and gives the confidence for performing the realistic integration. Received February 20, 2002; accepted July 7, 2002 Published online: February 20, 2003