Oceans at MIT

Striving to understand, harness and sustain Earth's defining frontier.

http://oceans.mit.edu

America/New_York

20171105T020000 -0400 -0500 20181104T020000 EST 20180311T020000 -0500 -0400 EDT 20170512T100000-n91e8qdrst0dg1c0kqh59dudk0@google.com 20180503T093227Z MIT Seminar | PAOC Chemical Oceanography and Biogeochemistry Identifying Traces of Primitive Life in Ancient Rocks The early life fossil record is based upon a limited number of often controversial graphitic microfossils. The main complication resides in the poor preservation of organic biosignatures in the (meta)sedimentary rock record. Biodegradation and fossilization processes, as well as the increase of temperature and pressure conditions during diagenesis and metamorphism inevitably alter the original biochemical signatures of organic molecules. Thus, at a certain stage, biogenic and abiotic organics may become very difficult to distinguish. During this talk, I will show how combining characterization of natural samples using advanced spectroscopic techniques (STXM-based XANES & Raman microspectroscopies) and simulation of fossilization processes in the laboratory sheds new light on the potential preservation of microorganism molecular biosignatures in ancient rocks. 20170512T100000 20170512T110000 Building E25, Room 119 0

COG3 Seminar – Julien Alleon (MIT)