Geology and palynology of the Triassic succession of Bjørnøya

The Triassic succession of Bjørnøya (200 m) comprises the Lower Triassic Urd Formation (65 m) of the Sassendalen Group, and the Middle and Upper Triassic Skuld Formation (135 m) of the Kapp Toscana Group. These units are separated by a condensed '.'Middle Triassic sequence represented by a phosphatic remainé conglomerate (0.2m).
The Urd Formation consists of grey to dark grey shales with yellow weathering dolomitic beds and nodules. Palynology indicates the oldest beds to be Diencrian; ammonoid faunas in the middle and upper part of the formation arc of Smithian age. The organic content (c. 1 %) includes kerogen of land and marine origin, reflecting a shallow marine depositional environment.
The Skuld Formation is dominated by grey shales with red weathering siderite nodules. There are minor coarsening upwards sequences; the highest bed exposed is a 20 m thick, very fine-grained sandstone. Palynomorphs indicate a late Ladinian age for the lower part of the formation, and macrofossils and palynomorphs indicate Ladinian to Carnian ages for the upper part. Sedimentary structures, a sparse marine fauna and microplankton indicate deposition in a shallow marine environment. The organic residues contain dominantly terrestrially derived kerogen.     

Laser-heated diamond anvil cell experiments at high pressure: Melting curve of nickel up to 700 kbar

Laser-heated experiments in a diamond anvil cell have been performed on high pressure melting of nickel up to 700 kbar. The laser heating system consists of diamond anvil cell, Nd:YAG and argon lasers, spectrograph with diode array, computer with software, CCD camera with monitor and optics. Experiments on melting of tungsten, nickel and platinum at 1 bar outside the diamond anvil cell and melting of nickel below 80 kbar in the cell were carried out to check the system for pressure and temperature measurements. The results show that for solid pressure medium the uncertainties in measurements of pressure at the experimental spot vary between ±5 kbar at 100 kbar and ±25 kbar at 660 kbar. Spectroradiometrically determined temperature is reliable within ±70 K. Melting was detected in situ by visual observation. The melting point of nickel at 660 kbar has been found to be 2557 ±66 K.     

Garnet-clinopyroxene geothermometer

A garnet-clinopyroxene geothermometer based on the available experimental data on compositions of coexisting phases in the system MgO-FeO-MnO-Al₂O₃-Na₂O-SiO₂ is as follows: $$T({\text{}}K) = \frac{{8288 + 0.0276 P {\text{(bar)}} + Q1 - Q2}}{{1.987 \ln K_{\text{D}} + 2.4083}}$$ where P is pressure, and Q1, Q2, and K _D are given by the following equations $$Q1 = 2,710{\text{(}}X_{{\text{Fe}}} - X_{{\text{Mg}}} {\text{)}} + 3,150{\text{ }}X_{{\text{Ca}}} + 2,600{\text{ }}X_{{\text{Mn}}} $$ (mole fractions in garnet) $$\begin{gathered}Q2 = - 6,594[X_{{\text{Fe}}} {\text{(}}X_{{\text{Fe}}} - 2X_{{\text{Mg}}} {\text{)]}} \hfill \\{\text{ }} - 12762{\text{ [}}X_{{\text{Fe}}} - X_{{\text{Mg}}} (1 - X_{{\text{Fe}}} {\text{)]}} \hfill \\{\text{ }} - 11,281[X_{{\text{Ca}}} (1 - X_{{\text{Al}}} ) - 2X_{{\text{Mg}}} 2X_{{\text{Ca}}} ] \hfill \\{\text{ + 6137[}}X_{{\text{Ca}}} (2X_{{\text{Mg}}} + X_{{\text{Al}}} )] \hfill \\{\text{ + 35,791[}}X_{{\text{Al}}} (1 - 2X_{{\text{Mg}}} )] \hfill \\{\text{ + 25,409[(}}X_{{\text{Ca}}} )^2 ] - 55,137[X_{{\text{Ca}}} (X_{{\text{Mg}}} - X_{{\text{Fe}}} )] \hfill \\{\text{ }} - 11,338[X_{{\text{Al}}} (X_{{\text{Fe}}} - X_{{\text{Mg}}} )] \hfill \\\end{gathered} $$ [mole fractions in clinopyroxene Mg = MgSiO₃, Fe = FeSiO₃, Ca = CaSiO₃, Al = (Al₂O₃-Na₂O)] K _D = (Fe/Mg) in garnet/(Fe/Mg) in clinopyroxene. Mn and Cr in clinopyroxene, when present in small concentrations are added to Fe and Al respectively. Fe is total Fe²⁺+Fe³⁺.     

Evaluation of reservoir temperatures and local utilization of geothermal waters of the Konkan Coast, India

Geochemical studies on fifteen geothermal manifestations (38–70°C) from the Konkan coast geothermal province of India have been used to evaluate the reservoir temperatures. Activity studies of the minerals and the waters present in the reservoirs suggest that the thermal waters are in equilibrium with montmorillonite, kaolinite and quartz at about 100°C. Reservoir temperatures of these geothermal systems as estimated by geochemical thermometers, are 88 to 128°C, and thus too low for economic electricity production.     

Hydromagnetic cylindrical shock in self-gravitating gas

Chisnell-Chester-Whitham method has been used to study the propagation of diverging hydromagnetic cylindrical shock through an infinitely electrically conducting self-gravitating gas having an initial density distribution ₀= r^-w where is the density at the axis of symmetry andw is a constant, simultaneously for the two cases, viz.: (i) when the shock is weak and (ii) when it is strong. The magnetic field is taken to be axial and initially of constant strength. Analytical relations for shock velocity and shock strength have been obtained. the expressions for the pressure, the density and the particle velocity immediately behind the shock have also been derived.     

Assessment of groundwater pollution due to tannery industries in and around Dindigul, Tamilnadu, India

The overexploitation of groundwater in some parts of the country induces water quality degradation. The untreated industrial effluents discharged on the surface causes severe groundwater pollution in the industrial belt of the country. This poses a problem of supply of hazard free drinking water in the rural parts of the country. There are about 80 tanneries operating in and around Dindigul town in upper Kodaganar river basin, Tamilnadu, India. The untreated effluents from the tanneries have considerably affected the quality of groundwater in this area. To assess the extent of groundwater deterioration, a detailed analysis of groundwater quality data has been carried out. The concentration of cations such as Calcium (Ca²⁺), Magnesium (Mg²⁺), Sodium (Na⁺) and Potassium (K⁺), and anions such as Bicarbonate (HCO₃^–), Sulphate (SO₄^2–), Chloride (Cl^–) and Nitrate (NO₃^–) in the groundwater have been studied. Apart from these constituents, pH, electrical conductivity (EC), total dissolved solid and total hardness (TH as CaCO₃) were also studied. The correlation of these constituents with the EC has been carried out. The highest correlation is observed between EC and chloride with a correlation coefficient of 0.99. Progressive reduction in correlation coefficients for Mg²⁺, (Na⁺ + K⁺), Ca²⁺ and SO₄^2– are observed as 0.91, 0.87, 0.86 and 0.56, respectively. It is found that the quality of groundwater in the area under investigation is deteriorated mainly due to extensive use of salt in the leather industries.     

Studies on the Effect of DDT on the Regeneration of Cutaneous Wounds in Mystus (mystus) vittatus Bl. (Bagridae)

The effects of DDT on the regeneration of cutaneous wounds has been studied in Mystus (mystus) vittatus. The fishes were locally collected, they were inflicted incised wounds surgically and kept in 0.01 and 0.15 ppm concentrations of DDT. The regenerating skin at different stages of development ranging from 15 min to 25 d after the injury was studied through microtomy sections. The following toxic effects were studied:

• A small amount of DDT accumulated in the subcutis at the 25 days stage,
• the regeneration of wounds under DDT stress has been slower, delayed or irregular,
• the secretion of fibrinous exudate has been copious,
• epithelization and fibroblastic activities have been slower,
• the higher concentration of 0.15 ppm of DDT produced more toxic effects than the lower concentration of 0.01 ppm,
• the earlier stages of wound healing up to 3 d have been more adversely affected than later stages.

     

Application of GIS for land-use/land-cover change analysis in a mountainous terrain

Integration of remote sensing data with other spatial/non-spatial data was carried out using ARC/INFO software package. A simple classification technique was adopted for land cover/land-use change analyses in relation to elevation, slope, aspect and bio-climatic classes. Suitability assessment of land where agricultural extension occurred between 1963 and 1993 was made using GIS software package. Expansion of agriculture and was found to be maximum in 2200-2400 m elevation zone and 20–30° slope classes. When topographic aspects were considered expansion was maximum on south east and west facing slopes. The loss of vegetal cover is estimated to be 15 per cent between 1963–1993. However regeneration of forest was found to be maximum in elevation ranges of 1600–2000 metre and mostly having 20–30° average slope, Land deterioration over the two mapping periods was identified and strategies were suggested to mitigate the problem.     

Terrain analysis of Panna District,Bundelkhand, Madhya Pradesh,using LANDSAT imagery

Visual interpretation of LANDSAT imagery in bands 6 and 7 covering Panna district, Bundelkhand, Madhya Pradesh was carried out for terrain analysis and present land use. The physiographic units viz. hills and hill ranges, escarpments, ridges, table-land, pediment, piedmont plain and sub-units of second order were identified and delineated using inter pretation elements. Area of each unit and sub-unit is calculated and presented in the table showing extent, tone, texture, shape and land use. Land use in relation to physiographic units is also described in the paper and shown in the form of small scale map. Visual interpretation technique helps in broad terrain analysis on scale 1:1 million. This information could be used for making a rapid resource inventory.     

Physiography of the tons basin,Western Himalaya

Landsat RBV imagery on 1:500,000 was interpreted to prepare small scale physiography map of the part of the Tons basin. Aerial photographs on 1:60,000 to 1:80,000 scale were interpreted to prepare medium scale physiography map of the basin. The basin has been sub-divided into three physiographic regions viz. High to very high mountains constituting of glaciated and temperate high mountains; Low to moderately high mountains and very low maountains. The physiographic regions have been further sub-divided based on landforms, slope and dissection index. The major physiographic units are summits, repose slopes, serrated ridges with horn/arates; mountain and valley glaciers, morains, solufluction terraces, intrenched incised river valleys, engrown valleys, alluvial terraces, rocky slopes/cliffs and debris.