Dr. Timothy Masterlark


Assistant Professor
Dept. of Geological Sciences
The University of Alabama
Tuscaloosa, AL 35487
phone: (205) 348-6289
fax: (205) 348-0818
email: masterlark@geo.ua.edu


Professional preparation
2005- , Assist. Professor, The University of Alabama.
2001-2005, Senior Scientist, SAIC/USGS EROS.
2000-2001, Post-doc, University of Wisconsin-Madison.
1986-1990, 82nd Airborne Division, US Army.

Education
Ph.D. (2000), Hydrogeology, University of Wisconsin-Madison.
M.S. (1996), Geophysics, University of Wisconsin-Madison.
B.S. (1994), Geology, University of Wisconsin-Eau Claire.
Deploying seismic equipment from M/V Performer, SEATOS Expedition, Indian Ocean. The SEATOS Expedition (May 2005) surveyed the seafloor along the Sunda Trench for evidence of rupture & tsunami-genesis associated with the 2004 M9 Sumatra-Andaman Earthquake. A camera crew from The Discovery Channel documented the expedition.


Vatnajokull, Iceland. Viewed from the east (June 2006).
Research synopsis: If you can describe it, we can build it.
Models provide the linkage between surface deformation and the inaccessible interior processes, such as fault-slip and magma intrusion. My research group focuses on developing innovational ABAQUS-based Finite Element Models (FEMs) that synthesize field, laboratory, GPS, and InSAR data to quantitatively simulate quasi-static earthquake and volcano deformation processes. We are equipped to simulate 1D, 2D, 3D, and axisymmetric elastic, poroelastic, viscoelastic (both linear & non-linear), and thermoelastic problem domains for use in both forward and inverse models. We are modelers and our efforts are governed by the following principle:

The reliability of model predictions depends on how well the model represents the natural system.

Current FEM projects include:
· Coseismic & postseismic deformation, stress-coupling, and tsunami-genesis of the 2004 M9 Sumatra-Andaman earthquake.
· Coseismic & postseismic deformation of the 1995 M8 Jalisco earthquake, Mexico.
· Deformation of active volcano & rift systems of Iceland.

Current graduate students:
· Kristin Hughes (Ph.D.) Virtual Sumatra-Andaman subduction zone.
· Haylee Dickinson (M.S.) Transient deformation of the Askja rift segment, Iceland.

For prospective students: The elements of a good modeler are: 1) Self-motivation; 2) Strong analytical skills; 3) Knowledge of geology and mechanics; 4) Creativity; and 5) Effective communication. Graduate students working under my supervision can expect an unsurpassed level of personal attention and will be afforded academic flexibility and the freedom to explore. My graduate students have exclusive use of the newly established Geodynamics & Active Deformation Laboratory -A self-contained computing facility specifically designed for intensive finite element modeling and visualization activities.

Teaching
Introductory Geology/Dynamic Earth (GEO101, 4cr.): Survey of the Earth, including plate tectonics; materials, internal and external processes; and natural hazards.

Earthquakes, Eruptions, and Civilization (GEO340, 3cr., W): This course investigates the development of human perceptions of tectonic events and their impact on civilization.

Geodynamics (GEO542, 3cr.): The overarching emphasis of this course is to develop quantitative expressions for geologic processes. Topics addressed include: elasticity and flexure of the Earth's lithosphere, heat conduction, fluid migration, poroelastic mechanics, and active deformation. Students are encouraged to consult with one another, explore ideas, ask questions, and develop and test multiple hypotheses.

Geologic Data Analysis (GEO525, 3cr.): This course presents theory and methods to quantitatively assess geologic data. Topics include: (1) Model formulation; (2) Matrix assembly, operations, inverse methods, and parameter estimation; and (3) An introduction to constructing ABAQUS-based FEMs.

Honors/Graduate Seminar (GEO435(6)/535(6)/635(6), 1cr.): I am the seminar Czar for this weekly event.

Synergistic activities
· NASA Earth Systems Scholar (NIP 2005 & ESS Fellowship 1996)
· SEATOS Expedition (Sponsored by The Discovery Channel 2005)
· Mentor for international & domestic aspiring modelers (Using ABAQUS)
· Earthquake research featured in Simulia-ABAQUS annual PR calendar (August, 2008).

Invited articles

Masterlark, T. (2007), Simulia Abaqus for Disaster Modeling , Geoconnexion International Magazine, November.

Masterlark, T. (2007), Modeling Earthquakes with Realistic Simulation Software, R&D Magazine, June.

Masterlark, T. (2007), Simulating the M9 Sumatra-Andaman Earthquake and Tsunami Source, ABAQUS INSIGHTS, Feb/Mar.

Masterlark, T. (2007), What Causes Tsunamies?, UA Research Magazine X.

Peer-reviewed publications
please email me to request a .pdf for any article listed below.

Masterlark, T. and K.L.H. Hughes (2008), The next generation of near-field deformation models of the Great Sumatra-Andaman Earthquake, Geology (currently in review).

Masterlark, T. (2007), Magma Intrusion and deformation predictions: Sensitivities to the Mogi assumptions, Journal of Geophysical Research 112, doi:10.1029/2006JB004860, 17 pp.

Fisher, D., D. Mosher, J.A. Austin, Jr., S. Gulick, T. Masterlark, and K. Moran (2007), Active deformation across the Sumatran forearc over the December 2004 Mw9.2 rupture, Geology 35, doi:10.1130/G22993A.1, 99-102.

Masterlark, T., Z Lu, and R Rykhus (2006), Thickness distribution of a cooling pyroclastic flow deposit: Optimization using InSAR, FEMs, and an adaptive mesh algorithm, Journal of Volcanology and Geothermal Research 150, 186-201.

Moran, S.C, O. Kwoun, T. Masterlark, and Z. Lu (2006), On the absence of InSAR-detected volcano deformation spanning the 1995-1996 and 1999 eruptions of Shishaldin Volcano, Alaska, Journal of Volcanology and Geothermal Research 150, 119-131.

Poland, M., R. Burgmann, D. Dzurisin, M. Lisowski, T. Masterlark, S. Owen and J. Fink (2006), Constraints on the mechanism of long-term, steady subsidence at Medicine Lake volcano, northern California, from GPS and precise leveling, Journal of Volcanology and Geothermal Research 150, 55-78.

Lu, Z., T. Masterlark, and D. Dzurisin (2005), Interferometric synthetic aperture (InSAR) study of Okmok volcano, Alaska: Magma supply dynamics and post-emplacement lava flow deformation, Journal of Geophysical Research 110, 10.1029/2004JB003148, 18 pp.

Masterlark, T., and Z. Lu (2004), Transient volcano deformation sources imaged with interferometric synthetic aperture radar: Application to Seguam Island, Alaska, Journal of Geophysical Research 109, doi:10.1029/2003JB002568, 17 pp.

Lu, Z., R. Rykhus, T. Masterlark, and K. Dean (2004), Mapping recent lava flows at Westdahl volcano, Alaska, using radar and optical satellite imagery, Remote Sensing of Environment 91, 345-353.

Masterlark, T. (2003), Finite element model predictions of static deformation from dislocation sources in a subduction zone: Sensitivities to homogeneous, isotropic, Poisson-solid, and half-space assumptions, Journal of Geophysical Research 108, doi:10.1029/2002JB002296, 17 pp.

Lu, Z., C. Wicks, Jr., D. Dzurisin, J. Power, W. Thatcher, and T. Masterlark (2003), Interferometric synthetic aperture radar studies of Alaska volcanoes, Earth Observation Magazine 12, 8-18.

Lu, Z., T. Masterlark, D. Dzurisin, R. Rykhus, and C. Wicks, Jr. (2003), Transient inflation rate detected with satellite interferometry and its implication to the plumbing system at Westdahl volcano, Alaska, Journal of Geophysical Research 108, doi:10.1029/2002JB002311, 17 pp.

Lu, Z., T. Masterlark, J. Power, D. Dzurisin, C. Wicks, Jr., and W. Thatcher (2002), Subsidence at Kiska volcano, western Aleutians, detected by satellite radar interferometry, Geophysical Research Letters 29, doi: 10.1029/2002GL014948, 4 pp.

Masterlark, T., and H.F. Wang (2002), Transient stress-coupling between the 1992 Landers and 1999 Hector Mine earthquakes, Bulletin of the Seismological Society of America 92, 1470-1486.

Marquez-Azua, B., C. DeMets, and T. Masterlark (2002), Strong interseismic coupling, fault afterslip, and viscoelastic flow before and after the Oct. 9, 1995 Jalisco-Colima earthquake: Continuous GPS measurements from Colima, Mexico, Geophysical Research Letters 29, 1029/2002GL014702, 4 pp.

Masterlark, T., C. DeMets, H.F. Wang, J. Stock, and O. Sanchez (2001), Homogeneous vs. heterogeneous subduction zone models: Coseismic and postseismic deformation, Geophysical Research Letters 28, 4047-4050.

Masterlark, T., and H. Wang (2000), Poroelastic coupling between the 1992 Landers and Big Bear earthquakes, Geophysical Research Letters 27, 3647-3650.

Masterlark, T., H. Wang, L. Chan, and Y. Che (1999), Coseismic pore pressure response estimated from tidal band prediction error filtering, Bulletin of the Seismological Society of America 89, 1439-1446.




Seismotectonic setting, 2004 M9 Sumatra-Andaman Earthquane (SAE). (a) Sumatra-Andaman Subduction zone. Rupture segments (red regions) from recent earthquakes (2000-2007) cover most of the plate boundary from the southeastern tip of Sumatra through the northern extent of the Andaman Islands. (b) SAE. Aftershock epicenters (yellow dots) illuminate the surface projection of the rupture, which initiated on the southeast portion of the fault and propagated 1200 km northward. Black triangles are near-field GPS sites. The red star marks the location of the SEATOS ROV dive site (see below). Abbreviations: Andaman Islands (AI), Burma Plate (BP), Indo-Australian Plate (IAP), Nicobar Islands (NI), Simeulue Island (SI), Great Sumatran Fault (GSF), Sunda Plate (SP), and West Sumatra Fault (WSF).


Viscoelastic relaxation - M9 Sumatra-Andaman Earthquake. This image is a portion of the simulated near-field region extracted from a regional-scale finite element model (FEM) of the M9 Sumatra-Andaman Earthquake (SAE). Coseismic slip of the SAE introduced enormous deviatoric stresses (red and blue represent high and null deviatoric stresses, respectively). The stress in the mantle decays via viscous flow, which induces postseismic deformation in the overlying elastic crust.


M/V Performer. SEATOS Expedition: The Discovery Channel's "Journey to the heart of the Tsunami" (May 2005).


Coseismic scarp, base of Sunda Trench. Total relief of the scarp (viewed from the northeast) is about 12m. This mosaic is assembled from ROV-images of the Sunda Trench (depth ~4500m) taken during SEATOS Expedition (May 2005).


GPS Campaign, near Jalisco, Mexico. (February 2001).


FEM: Augustine volcano, Alaska. This FEM simulates thermoelastic deformation of a cooling pyroclastic flow deposit.


FEM: Okmok volcano, Alaska. This FEM, which simulates observed InSAR deformation, allows us to quantify the behavior of restless magma.

Last updated: TM - Jan. 2008