Early Earth Focus Group
Chairs: Andrew D. Czaja and Martin Van Kranendonk
The search for life beyond Earth requires understanding the conditions under which life originates and evolves, the factors influencing the emergence of complex life, and the ability to interpret the “fingerprints” left by primitive biospheres on the geologic record or in the atmospheres of extrasolar planets. Such understanding must be informed by examination of the history of the only planet on which life is known to exist-the Earth. Hence, study of life and the environment on the early Earth is a critical aspect of astrobiology research.
The aim of the Early Earth Focus Group (EEFG) is to facilitate collaborative activities centered on this topic that bring together researchers from multiple NAI teams as well as researchers from outside the NAI (including researchers based outside the U.S.). To this end, the group currently includes approximately 120 researchers. These individuals all actively requested membership in the group.
The primary activity of the group has been to develop the case for organized stratigraphic drilling of ancient sedimentary intervals of unique astrobiological interest—a “mission to early Earth.” To this end, the group has sponsored a series of meetings and field expeditions, and ultimately proposed a “Deep Time Drilling Project” to begin with a set of three pilot drill cores in the Archean stratigraphy of Western Australia . These activities helped spur the creation of the NAI’s Astrobiology Drilling Program (ADP) in Fall 2003.
The major activity was a field expedition to Western Australia in the summer of 2001. The primary goals were to 1) obtain samples from the earliest geologic record ( Jack Hills region) and 2) to become familiar with the local stratigraphy and astrobiologically-relevant localities in order to develop concepts for a pilot astrobiology drilling project (Pilbara region).
A formal proposal for funding of the pilot project was submitted to the NAI and an update of the projects plans were provided at a “break out” session at the Astrobiology Science Conference. EEFG Initiated exploration of collaboration with researchers in Russia and Finland to sample sediments from the early Proterozoic. Discussions were initiated at the Russian Astrobiology Workshop in March and during the visit to Finland in June 2002.
The primary activity was the development of plans to integrate the planned drilling activities of the EEFG into the ADP of the NAI. The latter program is in many ways an outgrowth of the EEFG’s activities. It will serve as an “umbrella” for collaborative early Earth sampling activities under NAI auspices. Focus Group leadership also played a key role in formulating policies for the ADP.
2004 was dominated by preparations for the drilling activities of the Deep Time Drilling Project field expedition to Western Australia . EEFG continued work with the NAI Director to develop the ADP as a program that will facilitate both sampling and outreach to the broader astrobiology community.
The Early Earth Focus Group sponsored a joint NAI-NSF workshop on Deep Time Drilling at the Earth System Processes conference in Calgary, Canada, in August, 2005. This workshop was attended by ~ 50 people, including administrators from both organizations. Attendees provided overviews of ongoing and planning drilling projects and discussed the potential for collaborative efforts between the agencies, particularly with regard to sample storage, curation and distribution.
With the creation of the ADP, the “operational” aspects of the focus group are being relocated to an administrative committee (the Astrobiology Steering Committee) overseen by the NAI Director. This is an appropriate evolution, the net result of which will be that the future activities of the focus group will center on advisory/outreach functions rather than “mission planning”. Consequently, it was proposed that the name of the group change from “Mission to Early Earth Focus Group” to “Early Earth Focus Group.” The future activities of this refocused focus group remain to be developed.
Generation of initial science results from the Deep Time Drilling Project
This activity focused on geochemistry and geobiology of the McRae Shale in the Hamersley drill core. This core arrived at ASU in September, 2005. Due to damage during shipping, samples had to be carefully repacked. The core was available for sampling, in a suitably-equipped laboratory, beginning in January, 2006, at which time a PIs workshop was held at ASU. High stratigraphic resolution samples were obtained and characterized for stable isotopes and elemental abundances. Initial results were presented at the 2006 AbSciCon and submitted to the 2006 GSA meeting.
The group met during the 2008 Astrobiology Science Conference in Santa Clara, California.
The Early Earth Focus Group met at the 2012 Astrobiology Science conference in Atlanta, Georgia in April, 2012. The group of about 25 participants, ranging from graduate students to senior faculty, reviewed past activities and decided they liked the idea of field conferences. Martin Van Kranendonk and Malcolm Walter suggested that we tie the next field conference to plans they are already developing for a Shark Bay via Hamersley to Pilbara field trip in 2013. We also discussed having a workshop without walls (online) on an Early Earth theme at some sort of frequency. Nicolle Zellner from Albion College is willing to look into the logistics of setting this up.
The Early Earth Focus Group organized the “Hadean Earth-Moon System Workshop Without Walls”
The Early Earth Focus Group met at the 2010 Astrobiology Science Conference in League City, Texas.
The Early Earth Focus Group organized the Anaerobic Phototrophic Ecosystems
workshop from October 14-16, 2010.
Objectives of the workshop were to:
(1) Explore knowledge and uncertainty concerning the nature and distribution
of biomarkers and redox indicators in ancient rocks;
(2) Review what is known and unknown about modern anaerobic photosynthetic
ecosystems and their constituent organisms;
(3) Bridge the gap between researchers focusing on modern vs. ancient
(4) Provide opportunities for transfer of knowledge from senior to junior
(5) Plan a coordinated effort to understand the Green Lake ecosystem.
An overview of the meeting was published in a special issue of Geobiology.