Centre for Earth Sciences (CEaS)
Recent Submissions
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Quantification of Air-Sea CO2 exchange from the Southern Ocean during last deglaciation
Glacial and interglacial cycles are natural, rhythmic patterns of global climate. These cycles are primarily driven by variations in solar forcing, commonly known as Milankovitch cycles. The solar forcing includes eccentricity ... -
A geochemical and Ca, Sr, Nd isotopic study of the mantle: case studies of Kimberlites, Ophiolites, Abyssal Peridotites, and Layered Igneous Complexes
The Earth’s mantle constitutes 67% of its mass and despite mantle convection, it is geochemically and isotopically heterogeneous as evident from the compositions of mantle derived basaltic melts. It is a dynamic system ... -
An investigation into the axial dipole field and mantle-induced heterogeneity in Earth
The Earth’s axial dipole field is generated by dynamo action in the planet’s outer core. It is understood from observations that the convection in the outer core is influenced by the lateral heterogeneity in the overlying ... -
Damping of magnetic-Coriolis waves with imposed magnetic field orthogonal to the axis of rotation
Small-scale columnar structures (<10 km radius) in Earth's outer core result from inertial waves. In highly conducting fluid, magnetic field behaviour resembles stretched elastic strings and transmits disturbances as Alfvén ... -
Precambrian ocean, life, and syn to post-collisional records in the Himalayas (Kumaun)
The Ph.D. thesis focuses on the central sector of the Himalayas, i.e., Kumaun. Here, an attempt has been made to understand the poorly understood genesis of magnesium carbonates (sparry magnesite) of the Precambrian ... -
Constraining the Lithium Seawater Mass and Isotope Budget: Diagenetic Processes Through Marine Pore Waters
Silicate weathering consumes CO2 and controls cation fluxes to the ocean, thus playing a critical role in modulating long-term seawater chemistry and climate. There are very few markers of seawater chemistry whose value ... -
A stable Strontium isotopic (δ88/86Sr) study of seawater from the Bay of Bengal, coastal groundwater from the Bengal Basin, and the Ganges, Brahmaputra, Mahanadi, and Godavari rivers in India
Strontium (Sr) is an alkaline earth element that has four naturally occurring stable isotopes, 84Sr, 86Sr, 87Sr and 88Sr. During measurements of the radiogenic Sr isotope ratio (87Sr/86Sr), which is a widely used tracer ... -
Crustal evolution and tectonic processes of the Madras Block, India
The Neoarchaean (2.8–2.5 Ga) era in the earth’s history witnessed significant crustal growth related to the amalgamation and dispersion of ancient continents. The processes leading to the formation and destruction of the ... -
Reconstruction of temperature for Cenozoic and Proterozoic Ocean water using clumped isotope thermometry
Clumped isotope thermometry is a novel tool which is used for the determination of formation temperature for carbonates of diverse origin and understanding different marine and terrestrial processes. The primary interest ... -
Stable isotope and biogeochemical study of arsenic contamination in shallow groundwater at seasonal time intervals from West Bengal (Nadia district)
Seasonal monitoring of groundwater is essential to ascertain safe water for the population and ecosystem for drinking, irrigation, domestic purposes and to keep track of groundwater quality with natural (climate change ... -
Understanding the dynamics and evolution of cratons
The earth is the only rocky planet in the solar system that exhibits plate tectonics. One of the basic tenets of plate-tectonics is that it recycles the lithosphere within a few hundred million years. No oceanic lithosphere, ... -
A geochemical and Nd-Sr-Ca isotopic study of silicate weathering, crustal recycling and petrogenesis of carbonatites
Weathering of silicate rocks releases cations and anions which are transported to the oceans by rivers where calcium carbonate precipitates from the seawater. This process results in the net consumption of atmospheric ... -
Improved laboratory and computational models for thermal core–mantle interaction
The Earth's magnetic field is generated by thermochemical convection within its fluid outer core. The near-stationary high-latitude magnetic flux concentrations in the present day field indicate that convective ... -
A Geochemical and Sr, Ca, Mg, Li isotopic study of the Godavari River draining the Deccan basalts
Chemical weathering of continental silicate rocks releases cations and anions which are eventually precipitated as carbonates on the ocean floor. This entire process transfers carbon from the atmosphere to the oceans leading ... -
Tectonic evolution and tin mineralisation of the Karagwe–Ankole Belt, Rwanda
Studies of the tectonic evolution and associated ore genesis through time are fundamental to understanding Earth’s crustal growth, evolution, and related enrichment in metal deposits. The present PhD research work has ... -
A geochemical, Nd-Sr, and stable Ca isotopic study of siliciclastic and chemical sedimentary rocks, volcanic tuffs, and authigenic glauconites from Proterozoic sedimentary basins of India
The Archean-Proterozoic transition is marked by globally synchronous changes in tectonothermal and climatic patterns along with development of widespread epicontinental seas, with extensive shelf-sedimentation. The Indian ... -
Assessing the potential of stable calcium isotope ratios for paleotemperature reconstruction from studies of laboratory-precipitated inorganic carbonates and modern corals, fish otoliths and foraminifera
Determining paleo-seawater composition and temperature is critical for reconstructing Earth’s surface conditions through time and has major implications for understanding the origin and evolution of life on Earth. ... -
Investigating the role of mantle convection in affecting surface deformation and topography in the Indian plate and the India-Eurasia collision zone
The India-Eurasia collision zone has been a subject of various studies that have tried to explain the forces behind the high elevation and large scale continental deformation in this region. However, the relative contribution ... -
Geochemical and isotopic study of the Lonar and Dhala impact craters and jarosites from Kutch, India as analogues to understand planetary surface processes
Impact cratering and aqueous alteration are two important processes that have modified the Earth’s surface over time and better understanding of these processes on Earth allow us to understand the surface evolution of other ... -
Stable isotope geochemistry of carbonatites: New insights into the petrogenesis and evolution
Carbonatites are carbonate-rich magmatic rocks that are commonly thought of having a mantle origin and are thus, of great interest to geologist for understanding the chemical evolution of the upper mantle. This thesis ...
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