EarthScope: An Earth Science Program

Institute on the Lithosphere Asthenosphere Boundary -- Sep. 19-21, 2011 Portland, OR

The lithosphere is fundamental to the definition of tectonic plates and continents, and yet its dimensions, origins and evolution are still poorly understood. New observations at the interface between the strong lithosphere and weak asthenosphere hold clues as to the thermal, mechanical and chemical variations that create this boundary. Data from the EarthScope Facility have provided a wide variety of observations of the lithosphere-asthenosphere boundary (LAB), some of which lead to conflicting interpretations that confound the classical view of the lithosphere as a thermal boundary layer. This workshop brought together seismologists, dynamicists, experimentalists and petrologists to integrate these new observations into a new conceptual understanding of the LAB and to develop new ideas about Earth�s dynamic behavior that give rise to this feature.

Convenors: Clint Conrad, Colleen Dalton, Greg Hirth, Terry Plank, and Anne Trehu.

This is the second of an anticipated series of workshops to spawn virtual EarthScope Institutes intended to engage the scientific community on broad, emerging problems with transformative potential.

Jordan and Fyfe Penrose Conference report (December 1976): LINK to reprint

AGU EOS Workshop report (Volume 92, Number 51, 20 December 2011): LINK to AGU

Workshop Information

Workshop Presentations

Agenda [PDF]
Logistics [PDF]
Abstracts [PDF]
Participants [PDF]

National Science Foundation

EarthScope

Monday Morning - What is the LAB Dynamically?

TITLE: From Oceans to Continents!
AUTHOR: Robert Creeley
FILE: 1_2_LAB_Lenardic.pdf

TITLE: What is the LAB Dynamically: Lithosphere and Asthenosphere Rheology from Post-loading
AUTHOR: Roland B�rgmann
FILE: 1_3_LAB_Burgmann.pdf

TITLE: Constraints on lithosphere and mantle rheology from in-situ observations
AUTHOR: Shijie Zhong
FILE: 1_4_LAB_Zhong.pdf

Monday Morning - What is the LAB Geophysically?

TITLE: A seismological view of the lithosphere- asthenosphere boundary
AUTHOR: Toomey, Fischer, Schmerr, Rychert, Jones
FILE: 2_1_LAB_Fischer.pdf

TITLE: Imaging the lithosphere-asthenosphere boundary beneath an oceanic plate: A sharp interface at upwellings
AUTHOR: Toomey, Fischer, Schmerr, Rychert, Jones
FILE: 2_2_LAB_Schmerr.pdf

TITLE: Imaging the Destruction of Continental Lithosphere beneath Afar
AUTHOR: Toomey, Fischer, Schmerr, Rychert, Jones
FILE: 2_3_LAB_ Rychert.pdf

TITLE: Mapping the electrical lithosphere-asthenosphere boundary (eLAB) and its correspondence with seismic (sLAB) and petrological (pLAB) LABs
AUTHOR: Alan G. Jones
FILE: 2_4_LAB_Jones.pdf

Monday Afternoon - What is the LAB in the lab?

TITLE: The Structure of the LAB
AUTHOR: Karato, Smyth
FILE: /3_1_LAB_Karato.pdf

TITLE: Water planets and hydrogen in the earth's interior
AUTHOR: Karato, Smyth
FILE: /3_2_LAB_Smyth.pdf

Monday Afternoon - What forms the LAB?

TITLE: Going right to the source: Chemical Fingerprints of Continental Mantle Lithosphere
AUTHOR: Dick Lee, Warren, Reid
FILE: 4_3_LAB_Reid.pdf

Tuesday Morning - Composition of the Lithosphere?

TITLE: Going right to the source: Chemical Fingerprints of Continental Mantle Lithosphere
AUTHOR: Kelemen, Eaton, Dalton
FILE: 5_1_LAB_Eaton.pdf

TITLE: Compositional Distinction Between Oceanic and Cratonic Lithosphere
AUTHOR: Kelemen, Eaton, Dalton
FILE: 5_1_LAB_Kelemen.pdf

Tuesday Morning - Observations & Modeling of LAB Dynamics

TITLE: Intraplate Volcanism Induced by �Shear-Driven Upwelling�! Beneath the Lithosphere-Asthenospere Boundary
AUTHOR: Conrad
FILE: 6_1_LAB_Conrad.pdf

TITLE: Seismic Structure of Oceanic Lithosphere: Implications for the LAB?
AUTHOR: Gaherty, Lizarralde, Collins, Evans, Hirth, Brown
FILE: 6_3_LAB_Gaherty.pdf

TITLE: Microstructural Evolution of the Upper Mantle
AUTHOR: Hernlund Lowry, Freed, Skemer
FILE: 7_1_LAB_Skemer.pdf

Tuesday Afternoon - Evolution of the LAB

TITLE: Utilizing Postseismic Observations to Infer the Depth of the Lithosphere/Asthenosphere Boundary and the Nature of the Asthenosphere
AUTHOR: Freed
FILE: 7_2_LAB_Freed.pdf

TITLE: Toward In-Situ Estimation of Lishospheric Rheology
AUTHOR: Lowry
FILE: 7_3_LAB_Lowry.pdf

Tuesday Afternoon - Evolution of the LAB

TITLE: The Role of Small-scale Sublithospheric Convection in Generating and Modulating Oceanic Intraplate Volcanism
AUTHOR: Dunn, Ballmer, Artemieva, Hall
FILE: 8_1_LAB_Ballmer.pdf

Wednesday Morning - Melt & the LAB in the Western U.S.

Schulte-Pelkum, Roy, Holtzman, Till, Konter

Wednesday Morning - The LAB Beneath North America

Fouch, Yuan, Miller, van Wijk

Wednesday Afternoon - Lithosphere Evolution in the Western U.S.

Dueker, Humphreys, Gazel, Lekic, Schutt