Home
Research
Publications
Teaching
Resources
People
Allen CV
Seismo Lab
Earth & Planetary
UC Berkeley

RESEARCH INTERESTS

On this page:
3D Structure and Processes of the Earth's Interior
Earthquake Rupture Processes and Hazard Mitigation
Natural Hazards: Effects and Mitigation
Nuclear Verification

project links: DNA | ElarmS | Mendocino | FACES | OATS | Iceland | Nukes

3D Structure and Processes of the Earth's Interior

  • Tomographic imaging of the Earth's interior to constrain 3D structure using intergrated seismic techniques.
  • Mapping of anisotropic structure to determine strain fields and flow in the Earth's mantle.
  • Particularily interested in mantle upwelling processes, coupling with crustal deformation and surface volcanism.
  • Episodic tremor and slip (ETS): detection and characterization of low amplitude seismic tremor and slow slip events in subduction zones combined with structural imaging of the forearc to constrain the origin of ETS and any relation to megathrust activity.

DNA: Dynamic North America Models
The DNA models are a series of 3D tomographic velocity models of the North American Continent. The models make use of the Earthscope geophysical datasets as well as the permanent regional geophysical networks and short-term deployments. As the USArray Transportable Network rolls across the continent the additional data will be incorporated into these models. more...

The Mendocino Experiment
 A deployment of 80 broadband seismometers across the Mendocino Triple Junction (MTJ). The MTJ is where Cascadia subduction is transformed into the San Andreas Fault system. The experiment will track this process through high resolution imaging of the lower crust and uppermost mantle. more...

FACES:
Flexarry Along Cascadia
Experiment for Segmentation
 A deployment of 23 broadband seismometers along the length of Cascadia designed to study the process of episodic tremor and slip (ETS). The study will allow detailed mapping of ETS and image the structure of the forearc. more...

Episodic tremor and slip all along Cascadia
By combing data from geodetic and seismic sensors throughout Cascadia a catalog of ETS events has been developed for the subduction zone. From 2000 to 2006 there where 22 months during which an ETS event occurred, i.e. an average of one every 3.3 months. Find animations of ETS events, a one-page summary presented to NEPEC and a manuscript detailing the catalog, more...

Oregon Array for Teleseismic Study
OATS is a deployment of broadband seismic stations across Oregon. The line extends from the McDermitt Caldera to the northwest along the Newberry track, past the Newberry Caldera, over the High Cascades and on to the coast within ~100 km of the trench. more... Photos from the deployment


Preliminary seismic tomography images along the OATS array show the Juan de Fuca plate subducting beneath Oregon.

Seismic anisotropy observations across the study region. This fig comes from Xue and Allen 2006

Iceland: crust, mantle and flow
Here you can explore the models in your web browser. There are 2D slices through the various models, plus you can view and manipulate them using a Java3D viewer applet. Also download the raw model and data files. more...

Reprints:
Anisotropic structure - flow down asthenospheric channels
Squeezing the Iceland anomaly - model validation using SEM
The mantle study - imaging the plume head
The crustal study - 46 km thick crust in Iceland
Thin hot plume beneath Iceland - Constraining upwelling using diffraction effects

Earthquake Rupture Processes and Hazard Mitigation

  • Kinematics and dynamics of fault rupture.
  • Earthquake initiation processes.
  • Rapid magnitude determination from P-wave arrivals.
  • Earthquake early warning systems.

ElarmS: Earthquake Alarm Systems ...also visit: www.ElarmS.org

ElarmS is a suite of algorithms designed to (1) rapidly detect the initiation of an earthquake, (2) determine the size (magnitude) and location of the event, (3) predict the peak ground motion expected in the region around the event, and (4) issue a warning to people in locations that may expect significant ground motion. more...

Natural Hazards: Effects and Mitigation

  • The increasing impact of natural hazards on our tuned society.
  • Costs of future events.
  • Societal regeneration through hazard recovery.
Why the United States is becoming more vulnerable to natural disasters
A 1997 study by the U.S. National Science and Technology Council estimated the total cost of natural disasters the U.S. to be $54 billion per year, or approximately $1 billion per week. Why?

Nuclear Verification

False accusations, undetcted tests and the comprehensive test ban treaty (or lack thereof).
Brief introductions to:
Pakistan Nuclear Tests - May 28-30, 1998.
Indian Nuclear Tests - May 11-13, 1998.
Alleged Russian test on Novaya Zemlya - August 1997.