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Faculty

Torbjorn E TornqvistTorbjörn E. Törnqvist
Vokes Geology  Professor/Department Chair

Phone: 504-314-2221
Fax: (504) 865-5199
Email: tor@tulane.edu

Department of Earth & Environmental Sciences
Room 214 SSE Lab Complex
New Orleans, LA 70118

Quaternary Research Group

Education

Ph.D., Utrecht University, 1993
M.S., Utrecht University, 1988

Research Interests

Quaternary geology
Sea-level change
Fluvial and deltaic sedimentology
Sequence stratigraphy
Applied geochronology
Paleoclimatology

Selected Recent Publications

Törnqvist, T.E. and Hijma, M.P., 2012. Links between early Holocene ice-sheet decay, sea-level rise and abrupt climate change. Nature Geoscience, 5: 601-606.

Yu, S.-Y., Törnqvist, T.E. and Hu, P., 2012. Quantifying Holocene lithospheric subsidence rates underneath the Mississippi Delta. Earth and Planetary Science Letters, 331-332: 21-30.

Shen, Z., Törnqvist, T.E., Autin, W.J., Mateo, Z.R.P., Straub, K.M. and Mauz, B., 2012. Rapid and widespread response of the Lower Mississippi River to eustatic forcing during the last glacial-interglacial cycle. Geological Society of America Bulletin, 124: 690-704.

Li, Y.-X., Törnqvist, T.E., Nevitt, J.M. and Kohl, B., 2012. Synchronizing a sea-level jump, final Lake Agassiz drainage, and abrupt cooling 8200 years ago. Earth and Planetary Science Letters, 315-316: 41-50

Research Projects

Holocene sea level/climate connections.The sedimentary record of the Louisiana coast provides unique opportunities to investigate Holocene sea-level change at very high resolution, and to develop connections with paleoclimate records. Our efforts focus on a range of phenomena, including an abrupt sea-level rise associated with the 8.2 ka cooling event that was likely caused by the final drainage of glacial Lake Agassiz, as well as possible links between late Holocene sea-level change and climate episodes such as the Medieval Warm Period and the Little Ice Age.

Holocene sea-level records as a proxy for crustal movements.Our field investigations focus on the Mississippi Delta and adjacent US Gulf Coast and aim, among others, to quantify rates of differential crustal moments during the late Quaternary. We use a range of approaches for this purpose, anchored by Holocene relative sea-level records and augmented by studies of deformed Pleistocene surfaces and geophysical modeling.

Developing a postglacial sea-level database for the US Gulf Coast.In order to understand the spatial variability of natural, "background" rates of relative sea-level change that are critical to refine predictions of future sea-level rise on a regional scale, there is an urgent need to synthesize published sea-level data in a consistent format that includes a rigorous error assessment. We perform this type of work for the US Gulf Coast within the framework of a larger program that also covers the US Atlantic Coast. The ultimate goal is to make these data publicly available.

Late Quaternary evolution of the Lower Mississippi River.This project involves the collection of new borehole data, both from late Pleistocene strata in the Lower Mississippi Valley and late Holocene deposits in the Mississippi Delta. The key tool is the application of OSL dating to develop new geochronologic frameworks for clastic sedimentary successions that are otherwise difficult to date. Our goals include an improved understanding of the response of a continental-scale river to climate and sea-level change and deciphering fluviodeltaic accretion rates that can serve as analogs for coastal restoration projects by means of river diversions.

The continental margin as a critical interface for earthscape processes.Sea-level positions during the Last Glacial Maximum obtained by means of geophysical modeling serve as the foundation for a GIS-based analysis of the spatial relationship between the lowstand shoreline and the shelf edge along passive margins worldwide. Our objectives include, among others, to understand the nature of source-to-sink sediment flux during glacial-interglacial cycles and to investigate the currently poorly understood mechanisms of shelf-edge formation.

More detailed descriptions of this work can be found at the website of the Quaternary research group.

Courses Taught

EENS 1200 – Earth Systems
EENS 3270 – Sedimentation and Stratigraphy
EENS 3970 – Katrina, Global Change, and Public Policy
EENS 6260 – Paleoclimatology
EENS 6400 – The Scientific Enterprise
TIDE 1480 – Greening the Media

School of Science and Engineering, 201 Lindy Boggs Center, New Orleans, LA 70118 504-865-5764 sse@tulane.edu