One hour toward In-service Credit is available for teachers attending the Geology Open Night lectures.

Superstorm Sandy: Seismology Knows Best

Stony Brook University

7:30 PM Friday September 27, 2013
ESS 001

Superstorm Sandy was the second-costliest hurricane in United States history. The Hurricane killed at least 286 people along the path of the storm in seven countries and caused damage over $68 billion, a total surpassed only by Hurricane Katrina. So far, the tracking of a hurricane has been traditionally relied on satellite monitoring. The on-land monitoring stations are usually far away from the hurricane center, reducing their effectiveness in hurricane monitoring. In this talk, we will present a new novel way to track Superstorm Sandy using ground seismic data. The Hurricane energy is coupled to the ground and generates ground motions that are propagating inside the Earth and recorded by seismometers in the heartland of the United States. The seismic energy generated by a hurricane has been deemed useless in the past, as the seismic recordings appear similar to ordinary noise. However, we discovered that the Sandy-related ground motions, while indeed noise-like, correlate along the direction from Sandy. Such discovery makes it possible to retrieve the time differences of the seismic waves between the seismic stations along the direction of Sandy, and use them to determine the location of the Hurricane. At the same time, the recorded amplitudes of seismic waves can be used to track the strength of the Hurricane and the relative seismic energy along different directions can be use to decipher the symmetry of the Hurricane. We will show that seismology not only tracks the location and intensity of Hurricane Sandy, it also reveals the geometric symmetry of the Hurricane and other potential hazards that are not visible from satellite monitoring.

Professor Wen is a theoretical and observational seismologist and geodynamicist. His research is directed toward understanding the structure, dynamics, composition and evolution of the Earth and other planets. He uses seismic waves to probe the internal structure of the Earth and its change with time, combines seismic and mineral physics data to constrain the composition of the mantle, and develops geodynamical models of how Earth's internal processes govern the Earth's continental drift, surface uplift, surface large igneous province, geochemistry, intra-plate deformation and volcanism. He also has a strong interest in developing new techniques for simulating viscous flow and seismic wave propagation.

The Low Seismic Velocity Zone between the Lithosphere and the Asthenosphere: What does it consist of?

Prof. Donald Weidner

Stony Brook University

7:30 PM Friday October 25, 2013
ESS 001

Plate tectonics sees young oceanic lithosphere moving over the deep mantle. Below the lithosphere the velocity of seismic waves decreases and then increases in the asthenosphere. This low seismic velocity zone has been interpreted as a decoupling zone between the lithosphere and the asthenosphere. It is possible that partial melting may be playing a role in decreasing the seismic velocity in this zone.

Donald Weidner is a Distinguished Professor of Geosciences whose research currently focuses on using laboratory studies of Earth materials to provide constraints on the state and evolution of the Earth. It is now possible to attain rheologic and acoustic properties of mantle materials at pressure and temperature conditions equivalent to those in the Earth's mantle. The ultimate goals of this research are to define the physical and chemical state as well as the dynamic processes of the Earth's mantle and crust

Exotic chemistry at extreme conditions: from new materials to models of planetary interiors

Artem Oganov

Stony Brook University

7:30 PM Friday November 22, 2013
ESS 001

Thanks to powerful evolutionary algorithms, in particular to the USPEX method [1-3], it is now possible to predict both the stable compounds and their crystal structures at arbitraryP,T-conditions, given just the set of chemical elements. Recent developments include the extension of this algorithm to molecular crystals [4] (which allowed large structures to be handled easily, leading to revision of high-pressure structures of Mg(BH4)2 [5], proving earlier proposed “experimental” structure to be incorrect) and a new technique called evolutionary metadynamics [6].

Some of the results that he will discuss include:

1. Theoretical and experimental evidence for a new stable high-pressure phase of boron, γ-B [7], showing superhardness and charge transfer between boron atoms.

2. New insulating and optically transparent, and experimentally confirmed, form of sodium [8].

3. Establishment of the structure of a carbon allotrope – M-carbon [1,9].

4. Predicted reactivity of noble gases under moderate pressures – Xe [10] and even He.

5. Predicted stability of “impossible” chemical compounds – such as Na3Cl, Na2Cl, Na3Cl2, NaCl3, NaCl7 [11], Mg3O2 and MgO2 [12]. These compounds become stable under pressure and we already have compelling experimental evidence for some of them [11].

Artem Oganov is a professor in the Departments of Geosciences and Physics and Astronomy. His multidisciplinary research is centered on theoretical and computational physics leading to the:

Development of simulation methodologies and their application to studies of minerals at high pressures and temperatures, and to design of new materials.

Understanding the factors governing the structure and properties of solids, their structural, electronic, and magnetic transitions.

References
[1] Oganov A.R., Glass C.W., J.Chem.Phys. 124, 244704 (2006).
[2] Oganov A.R., Lyakhov A.O., Valle M., Acc. Chem. Res. 44, 227-237 (2011).
[3] Lyakhov A.O., Oganov A.R., Stokes H.T., Zhu Q., Comp. Phys. Comm. 184, 1172-1182 (2013).
[4] Zhu Q., Oganov A.R., Glass C.W., Stokes H.T., Acta Cryst. B68, 215-226 (2012).
[5] Zhou X.-F., Oganov A.R., Qian G.R., Zhu Q., Phys. Rev. Lett. 109, 245503 (2012).
[6] Zhu Q., Oganov A.R., Lyakhov A.O., Cryst.Eng.Comm. 14, 3596-3601 (2012).
[7] Oganov A.R., Chen J., Gatti C., et al., Nature 457, 863 (2009).
[8] Ma Y., Eremets M.I., Oganov A.R., et al., Nature 458, 182 (2009).
[9] Boulfelfel S.E., Oganov A.R., Leoni S., Scientific Reports 2, art. 471 (2012).
[10] Zhu Q., Jung D.Y., Oganov A.R., et al., Nature Chemistry 5, 61-65 (2013).
[11] Zhang W.W., Oganov A.R., Goncharov A.F., et al., http://arxiv.org/abs/1211.3644(2013).
[12] Zhu Q., Oganov A.R., Lyakhov A.O., Phys. Chem. Chem. Phys. 15, 7796-7700 (2013).

Geology Open Night

Fall 2013

There will be Refreshments and Demonstrations after the Geology Open Night Presentations.

Admission is Free!!

Superstorm Sandy: Seismology Knows Best

The Low Seismic Velocity Zone between the Lithosphere and the Asthenosphere: What does it consist of?

Exotic chemistry at extreme conditions: from new materials to models of planetary interiors

There will be Refreshments and Demonstrations after the Presentations.

Admission is FREE!