The largest geophysics conference in the world will be held in Washington DC this year. I'll be there presenting some new results on North American lithospheric structure - see abstract below.
If you are a prospective student or post-doc (or simply interested in chatting about fun science) attending AGU then I encourage you to get in touch with me; I would be happy to make time to meet with you.
In case you're interested, here are some sessions that I will be following with alert interest and great concern (in no particular order):
The deep structure of North American lithosphere illuminated by complementary seismic data types
Zachary Eilon, Karen M. Fischer, Colleen A. Dalton
The internal structure of continental lithosphere holds the key to our understanding of plate tectonic cycles and the long-term stability of cratons. Detailed imaging of the upper mantle has the potential to reveal chemical alteration, deformation fabric, thermal structure, and melt distribution, providing not only a contemporary snapshot but also an integrated history of the interactions between the Earth’s surface and its deep interior. We apply a transdimensional, hierarchical Bayesian inversion parameterised using piecewise discontinuous splines to solve for 1-D radially anisotropic shear velocity models of crust and upper mantle beneath long-lived stations across North America. The advantages of a Bayesian approach include quantitative uncertainty estimation and the ability to modularly incorporate multiple data types; we use Rayleigh wave and Love wave phase velocities from earthquakes and ambient noise, Rayleigh wave ellipticity ratios, and both P-sandS-pconverted phases. Taken jointly, this combination of data types provides excellent constraints on absolute velocities, crustal structure, and sharp gradients in velocity within or at the base of the lithosphere. We find that S-pphases are essential to capture accurately the characteristics of deep velocity gradients, such as those seen widely but discontinuously in the cratonic mid-lithosphere. Observed structures include shallow melt and adiabatic geotherms immediately beneath thin lithosphere in portions of the western US, as well as intra-lithospheric low-velocity zones beneath the cratons that have amplitude and depth consistent with new data on exotic lithologies associated with subduction-derived fluid reaction products.
Non-specialist/jargon version: At the heart of many continents lie large regions of the Earth’s tectonic plates that appear to be much older than their surroundings. We don’t yet understand how these stable regions were formed billions of years ago, or exactly why they are so resistant to being broken up or squished into mountains as vast forces act upon them. Here we use a new combination of types of seismic waves – Earth vibrations set off by distant earthquakes – to assess the properties of these ancient continental regions and the younger, weaker material that surrounds them. Different types of seismic waves are good for pinpointing certain individual properties of the Earth; by taking into account the information from multiple data types simultaneously, we can get a much better understanding of the internal structure of the tectonic plates and try to answer questions about how they were produced and how they have evolved – or not – over time.