I will cover three linked approaches, namely high precision analyses of (i) nucleosynthetic isotope anomalies, (ii) radiogenic isotopes
and (iii) trace elements.
The radiogenic isotopes
accumulate in the water and provide an estimate of how long the water has been buried.
The longer a fluid sits in the Earth over time, the more it interacts with the rock and creates radiogenic isotopes
of the noble gases.
However, little work has been done so far on the isotopic characteristics of oil shale, especially radiogenic isotopes
The Earth has cooled since its formation, yet the decay of radiogenic isotopes
New ages obtained are more consistent with the geological record, which opens new perspectives in crustal evolution studies based on radiogenic isotopes
," he said.
Drishnaswami through clever use of natural radioactive and radiogenic isotopes
and selected elements have been able to investigate the details and determine the time scales of chemical scavenging and solute-particle interactions in the sea and ground waters, sedimentary processes on the sea and lake beds, growth and turnover of ferro-manganese deposits, river-ocean interactions and material transport through estuaries, air-sea gas exchange of CO2 and erosion of the Himalaya and the Deccan Traps on the chemical and isotopic evolution of the oceans and long term global change.
Clearly, metasomatism coincident with magmatism is important, but it cannot yield the large variations in daughter radiogenic isotopes
observed among islands because they require millions or billions of years to develop from parent isotopes having long half-lives.
General topics include basic principles of atomic physics, including nuclear systematics decay modes of radionuclides, radioactive decay and geochronometry, radiogenic isotope
geochronometers, including a complete range of methods, the geochemistry of radiogenic isotopes
, including igneous rocks, water, and sediment, and the oceans, short-lived radionuclides, and fractionation of stable isotopes.
in seawater and sedimentary systems.
By measuring the proportions of radiogenic isotopes
(nuclides formed by radioactive decay at known rates), it is possible to fix the time of a rock's crystallization.
(isotopes produced by radioactive decay of parent isotopes--lead 206 produced by decay of uranium 238, for instance) are important natural tracers for determining when rocks were formed.