In an attempt to find novel anti-mycobacterial agents, novel acetylene containing 2-(2-hydrazinyl... more In an attempt to find novel anti-mycobacterial agents, novel acetylene containing 2-(2-hydrazinyl)thiazole derivatives have been synthesized and evaluated against Mycobacterium tuberculosis.
Electron Paramagnetic Resonance (EPR) is one of the modern techniques useful in dating events tha... more Electron Paramagnetic Resonance (EPR) is one of the modern techniques useful in dating events that are up to 1 million years old and hence very useful in understanding various geologi-cal events. We have made a preliminary attempt to date marine shells found on a beach situated 12 km north of Pondicherry, on the East Coast of India. These samples for dating had been col-lected 2 feet below the surface at 0 m, 30 m and 60 m away from the shoreline towards the west (land). Each sample was divided into four sets three of which were given an additive dose (AD) of 405 Gy, 810 Gy and 1620 Gy. All the samples show similar EPR spectra having g-values g A = 2.0057, g B = 2.0037, g C =2.0007 and g D = 1.9997 corresponding to freely rotating SO 2 – , iso-tropic SO 3 – , freely rotating CO 2 – and orthorhombic CO 2 – , respectively. Absorption lines at g A = 2.0057, g B = 2.0037 and g D = 1.9997 have been used to estimate the ages, assuming the external dose rate to be 1.12 mGy/a. The calculate...
Polymetallic sulfides from two hydrothermal chimneys and talus deposit from the Vienna Woods fiel... more Polymetallic sulfides from two hydrothermal chimneys and talus deposit from the Vienna Woods field of Manus Basin were studied for mineralogy, elemental composition, and S-isotope ratio to understand their evolution. The factors including the nature of source fluid, mineral paragenesis, and related geochemical processes have been discussed. Mineralogy and elemental concentration of Cu and Fe-rich large chimney at the central part of this hydrothermal field was completely different from the smaller Zn-rich peripheral chimney and Fe-rich talus deposit, suggesting the variable degree of alterations generate physico-chemically different source fluids responsible for these hydrothermal structures. Similarly, S-isotope ratios also indicate chemically diverse fluids and different modes of precipitation were involved in their evolution. Distinct mineral zonings and associated elemental and isotopic compositions within individual deposit confirm paragenetic shifts were involved during their growth process.
... Here the rocks were deep yellow coloured which changes to pale-yellow upwards. Shiny white po... more ... Here the rocks were deep yellow coloured which changes to pale-yellow upwards. Shiny white por-tions of feldspar altering to clay could be seen in Page 4. 548 R Deepthy and S Balakrishnan Figure 2. Photographs of weathering profiles in and around Banasandra. ...
Two possible models are available for the generation of komatiitic melts from upper mantle sourc... more Two possible models are available for the generation of komatiitic melts from upper mantle sources: (1) large extents of melting at relatively low pressures and (2) low extents of pseudoinvariant melting at high pressures. For the partial melting of olivine-dominated upper mantle and generation of komatiitic magmas, the [Mg]-[Fe] diagram calculated from olivine-melt KD data is potentially useful in estimating the physical conditions of melting and in evaluating Fe/Mg ratios of mantle sources. Application of this diagram to a suite of komatiitic amphibolites derived by different extents of melting of similar sources from the Kolar Schist Belt, south India, indicates that (1) their magmas were derived at pressures ranging from 3 to 7 GPa by different extents of melting; (2) melt generation occurred in adiabati- cally rising deep mantle diapirs; and (3) diapiric mantle sources had higher Fe/Mg ratios than the undepleted Lesotho garnet lherzolite (PHN 1611). Komatiitic rocks from other Archean terranes in the [Mg]-[Fe] diagram suggests a range of pressures and degree of melting that agree with those proposed from high pressure experimental studies. Although some komatiitic rocks have geochemical features and conditions of melting that may require residual garnet in the magma source regions, such geochemical features can also be inherited from sources without much residual garnet. This is possible if the sources had undergone high pressure melt addition at the time of melting.
In an attempt to find novel anti-mycobacterial agents, novel acetylene containing 2-(2-hydrazinyl... more In an attempt to find novel anti-mycobacterial agents, novel acetylene containing 2-(2-hydrazinyl)thiazole derivatives have been synthesized and evaluated against Mycobacterium tuberculosis.
Electron Paramagnetic Resonance (EPR) is one of the modern techniques useful in dating events tha... more Electron Paramagnetic Resonance (EPR) is one of the modern techniques useful in dating events that are up to 1 million years old and hence very useful in understanding various geologi-cal events. We have made a preliminary attempt to date marine shells found on a beach situated 12 km north of Pondicherry, on the East Coast of India. These samples for dating had been col-lected 2 feet below the surface at 0 m, 30 m and 60 m away from the shoreline towards the west (land). Each sample was divided into four sets three of which were given an additive dose (AD) of 405 Gy, 810 Gy and 1620 Gy. All the samples show similar EPR spectra having g-values g A = 2.0057, g B = 2.0037, g C =2.0007 and g D = 1.9997 corresponding to freely rotating SO 2 – , iso-tropic SO 3 – , freely rotating CO 2 – and orthorhombic CO 2 – , respectively. Absorption lines at g A = 2.0057, g B = 2.0037 and g D = 1.9997 have been used to estimate the ages, assuming the external dose rate to be 1.12 mGy/a. The calculate...
Polymetallic sulfides from two hydrothermal chimneys and talus deposit from the Vienna Woods fiel... more Polymetallic sulfides from two hydrothermal chimneys and talus deposit from the Vienna Woods field of Manus Basin were studied for mineralogy, elemental composition, and S-isotope ratio to understand their evolution. The factors including the nature of source fluid, mineral paragenesis, and related geochemical processes have been discussed. Mineralogy and elemental concentration of Cu and Fe-rich large chimney at the central part of this hydrothermal field was completely different from the smaller Zn-rich peripheral chimney and Fe-rich talus deposit, suggesting the variable degree of alterations generate physico-chemically different source fluids responsible for these hydrothermal structures. Similarly, S-isotope ratios also indicate chemically diverse fluids and different modes of precipitation were involved in their evolution. Distinct mineral zonings and associated elemental and isotopic compositions within individual deposit confirm paragenetic shifts were involved during their growth process.
... Here the rocks were deep yellow coloured which changes to pale-yellow upwards. Shiny white po... more ... Here the rocks were deep yellow coloured which changes to pale-yellow upwards. Shiny white por-tions of feldspar altering to clay could be seen in Page 4. 548 R Deepthy and S Balakrishnan Figure 2. Photographs of weathering profiles in and around Banasandra. ...
Two possible models are available for the generation of komatiitic melts from upper mantle sourc... more Two possible models are available for the generation of komatiitic melts from upper mantle sources: (1) large extents of melting at relatively low pressures and (2) low extents of pseudoinvariant melting at high pressures. For the partial melting of olivine-dominated upper mantle and generation of komatiitic magmas, the [Mg]-[Fe] diagram calculated from olivine-melt KD data is potentially useful in estimating the physical conditions of melting and in evaluating Fe/Mg ratios of mantle sources. Application of this diagram to a suite of komatiitic amphibolites derived by different extents of melting of similar sources from the Kolar Schist Belt, south India, indicates that (1) their magmas were derived at pressures ranging from 3 to 7 GPa by different extents of melting; (2) melt generation occurred in adiabati- cally rising deep mantle diapirs; and (3) diapiric mantle sources had higher Fe/Mg ratios than the undepleted Lesotho garnet lherzolite (PHN 1611). Komatiitic rocks from other Archean terranes in the [Mg]-[Fe] diagram suggests a range of pressures and degree of melting that agree with those proposed from high pressure experimental studies. Although some komatiitic rocks have geochemical features and conditions of melting that may require residual garnet in the magma source regions, such geochemical features can also be inherited from sources without much residual garnet. This is possible if the sources had undergone high pressure melt addition at the time of melting.
Uploads
extents of melting of similar sources from the Kolar Schist Belt, south India, indicates that (1) their magmas were derived at pressures ranging from 3 to 7 GPa by different extents of melting; (2) melt generation occurred in adiabati- cally rising deep mantle diapirs; and (3) diapiric mantle sources had higher Fe/Mg ratios than the undepleted Lesotho garnet lherzolite (PHN 1611). Komatiitic rocks from other Archean terranes in the [Mg]-[Fe] diagram suggests a range of pressures and degree of melting that agree with those proposed from high pressure experimental studies. Although some komatiitic rocks have geochemical features and conditions of melting that may require residual garnet in the magma source regions, such geochemical features can also be inherited from sources without much residual garnet. This is possible if the sources had undergone high pressure melt addition at the time of melting.
extents of melting of similar sources from the Kolar Schist Belt, south India, indicates that (1) their magmas were derived at pressures ranging from 3 to 7 GPa by different extents of melting; (2) melt generation occurred in adiabati- cally rising deep mantle diapirs; and (3) diapiric mantle sources had higher Fe/Mg ratios than the undepleted Lesotho garnet lherzolite (PHN 1611). Komatiitic rocks from other Archean terranes in the [Mg]-[Fe] diagram suggests a range of pressures and degree of melting that agree with those proposed from high pressure experimental studies. Although some komatiitic rocks have geochemical features and conditions of melting that may require residual garnet in the magma source regions, such geochemical features can also be inherited from sources without much residual garnet. This is possible if the sources had undergone high pressure melt addition at the time of melting.