The following Plenary Lectures will be given at Goldschmidt 2007:
The Geochemical Society Presidential Lecture
Friday August 24th, 09:15:
Bedrock to Soil: Earth's Weathering Engine
The surface of the earth acts as a weathering engine that grinds and solubilizes rocks, sculpts landscapes, and nourishes ecosystems. New data and models are providing answers to how the biological, chemical, and physical processes couple within this engine in response to changing tectonics, climate, and anthropogenic activity.
The Gast Lecture
Tuesday August 21st, 09:15
From Microbes to Mountains: Molecular Signatures of Life and its Environment
Biomarkers provide rich information about ancient environments and past climatic change. Molecular signatures are not simple recorders of material or physical properties in the past, and their interpretation demands an understanding of biological processes. This presentation will highlight the importance of ecological and physiological influences on molecular records of paleoclimate and paleoaltimetry.
Making the Earth in Five Days
Monday August 20th, 09:15
Terrestrial Planet Formation: Our Solar System and Extra-solar Worlds
The recent results of dynamical modeling of terrestrial planets formation are quite consistent with the available constraints and provide a framework for the interpretation of geochemical data. The terrestrial planet formation process can be extrapolated to systems characterized by different orbital properties of the giant planets or disk masses. This gives a first indication of the likelihood that Earths exist in extra-solar planetary systems.
Tuesday August 21st, 08:30
Magmatism and the Evolution of the Earth's Interior
Partial melting causes planetary differentiation and so the times and depths at which melting has occurred are keys to understanding Earth's evolution. Thermal modeling, high-pressure melt physics and both experimental and theoretical phase equilibria are coming together to constrain melt compositions and the physical processes of separation of liquids and solids at all mantle pressures.
Wednesday August 22nd, 08:30
Evidence of the Earliest Crust on Earth
Detrital zircons from Western Australia dating 4.4-4.0 Ga, without identified parent rocks, are the only direct evidence of the first 500 myr on Earth. The picture emerges of an early differentiated buoyant crust, cool surface temperatures, and oceans that were hospitable for life by 4.2 Ga and perhaps earlier.
Thursday August 23rd, 08:30
The Chemistry of Earth's Dynamic Surface
Cosmogenic nuclide methods and related geochemical techniques are providing new insights into how chemical weathering and physical erosion shape the surface of the Earth and its living environment. The emerging view is of a highly dynamic system in which chemical weathering and physical erosion may be tightly coupled to climatic and tectonic forcing, and to each other.
Friday August 24th, 08:30
Molecular Fossils and Early Life on Earth
Molecular fossils, or biomarkers, are preserved in billion year old sedimentary rocks and describe environments that were different from anything observed later in Earth history. However, many biomarkers and their biological sources remain unkown. Environmental genomics, the study of genomes of microorganisms in modern environments without cultivation, may fill the gaps and help us understand Earth's early ecosystems.