Big Ideas in Volcanology #08:


#08.6 _ Other science fields and new techniques can help develop the current theories

Alone, volcanology and generically geology can’t fully explain most of the processes involved in the dynamics of Earth’s hydrosphere. For this reason, interaction with other sciences are of crucial importance. Among these, planetary science, atmospheric science, paleochemistry, astrobiology and many others.

For example, radiogenic nuclides have been widely exploited in geochronology but represent also an important tool for the exploration of this Big Idea. If compared to the quantity of the radioactive 'parent isotope' in a system, the quantity of the radiogenic 'daughter product' is used as a radiometric dating tool.

Some of the most important radiogenic isotope systems used in geology

Radiogenic isotopes tracers also permit to measure the age of a rock exploiting its “DNA like” (or “fingerprints”, if you prefer!) evidences. Variations in the abundance of these isotopes compared with the quantity of a non-radiogenic isotope of the same element, can reveal information about the age of a rock or the source of air or water.

In isotope geochemistry, the enrichment δ represent the ratio of heavy isotope to light isotope in the sample over the ratio of a standard:

In the equation, the two stable isotopes of carbon (i.e. 12C and 13C) are ratioed. Other stable isotopes exploited in geology are 14N and 15N (measure the amount of exchange of air between the stratosphere and troposphere using data from the greenhouse gas N2O) and 16O, 17O and 18O (track water movement, paleoclimate and atmospheric gases such as O3 and CO2). Examples of radiogenic isotopes of geological interest are Ar-Ar, K-Ar, Pb-Pb, U-Pb, Sm-Nd,


Earth’s hydrosphere comes from Volcanic Degassing

#08.1                    #08.2                    #08.3                    #08.4                    #08.5                    #08.6