Colloquium Series: "Earth's Deep Carbon Cycle - Origin, Ingassing, Storage, and Outgassing"

Date: 

Monday, September 21, 2015, 4:00pm to 5:00pm

Location: 

Haller Hall (Geology Musem 102)

Speaker: Dr. Rajdeep Dasgupta (Rice University)

Abstract:

Earth is unique among the terrestrial planets in our solar system in having a fluid envelope that fosters life. The secrets behind Earth’s habitable climate are well-tuned cycles of carbon (C) and other volatiles. While on time-scales of ten to thousands of years the chemistry of fluids in the atmosphere, hydrosphere, and biosphere is dictated by fluxes of carbon between near surface reservoirs, over hundreds of millions to billions of years it is maintained by chemical interactions of carbon between Earth’s interior, more specifically the mantle, and the exosphere. This is because of the fact that the estimated total mass of C in the mantle is greater than that observed in the exosphere and the average residence time of carbon in the mantle is between 1 and 4 Ga. But how did Earth’s mantle attain and maintain the inventory of mantle carbon over geologic time? And is the residence time of carbon in the mantle, as constrained by the present-day fluxes, a true reflection of carbon ingassing and outgassing rates throughout Earth’s history? Also, when in the planet’s history did its mantle carbon inventory become established and how did it change through geologic time? The answers to these questions are important because of carbon’s importance in a number of fields of Earth sciences. In this presentation, I will attempt to shed light onto some of these topics.

About Rajdeep:

Rajdeep Dasgupta is an Earth scientist, who specializes in magmatic and other deep processes of Earth and terrestrial planets. Rajdeep was born and raised in Kolkata (formerly Calcutta), West Bengal, India. He studied geology in the undergraduate days to try something different and to fulfill his passion for nature and chemistry. After finishing both BSc and MSc degree from Jadavpur University, India in 1998 and 2000, respectively, he moved to the US to pursue doctoral research. Rajdeep obtained his PhD from University of Minnesota, Twin Cities, MN in 2006. He also held a two-year post-doctoral research fellow position in Columbia University before joining Rice University, Houston, TX as a faculty member of Earth Science in 2008. 
Raj’s research group at Rice investigates differentiation of Earth and other terrestrial planetary bodies chiefly using high pressure-temperature laboratory experiments. An overarching theme of his research is the role of volatile species such as carbon, sulfur, and water in evolution and properties of the planets from core to atmosphere and from the time of planet formation to the modern framework of plate-tectonic cycles. Dasgupta’s research has received recognition through a Clarke medal of the Geochemical Society (GS; 2011), Hisashi Kuno award of the Volcanology, Petrology, and Geochemistry section of the American Geophysical Union (2012), and a James B. Macelwane medal of the AGU (2014). He has also won one of the Packard Fellowships for Science and Engineering in 2010 and an NSF-CAREER grant in 2013.

Please see attached background reading relating to this talk

dasgupta_2013.pdf1.57 MB