UTIG RESEARCH PROJECTS ARCHIVE

Principal Investigator: Paul Mann
Graduate Student: Rob Rogers
Funding Agency: The Petroleum Research Fund, American Chemical Society

Abstract
Three tectonic models have been proposed to explain areas of late Cretaceous and early Tertiary folding and thrust faulting on the Chortis continental block of the northwestern Caribbean plate.  Two of these tectonic models are similar in their prediction of localized contraction either in suture zones or along strike-slip faults.  In a third model, continental rocks of the Chortis block are interpreted as the southern, offset extension of the regional-scale Laramide-age fold-thrust belt of southern Mexico.  The offset has occurred along the Motagua-Polochic strike-slip fault system that forms the present-day northern boundary of the Chortis block.  We favor the third model because of our previous work documenting large-scale offset on this fault system and because one of us (Rogers) has mapped a remote area of eastern Honduras (Montana de Colon) that is very similar to the stratigraphy and style of contractional deformation to the Laramide-age belt of southern Mexico.

We propose the following tasks to better establish the extent of this largely buried and poorly dated foldbelt in eastern Honduras and its offshore extension (Nicaraguan Rise) and to test the stratigraphic and tectonic correlations between the presumably offset rocks of Honduras and Mexico: 1) use structural mapping to determine the fault and fold kinematics of the low-grade metamorphic rocks northeast of the Montana de Colon; 2) use structural methods to determine the fault and fold kinematics of the mainly carbonate rocks of the Montanas de Colon; 3) conduct onshore field work in the savannas separating the Montanas de Colon and the Caribbean Sea to better constrain the extent of the foldbelt and the biostratigraphic ages of overlying clastic wedge deposits shed off the foldbelt using satellite radar data to identify small but critical outcrops; 4) correlate the ages of these clastic wedges to those of Eocene-Oligocene and Miocene-Recent age described by Binig (1990) to the north and west in the Gulf of Honduras; 5) map the extent and geometries of offshore clastic wedges north and east of Honduras using existing seismic reflection profiles at the UT Institute for Geophysics.  By documenting the regional stratigraphic and structural framework of eastern Honduras, this work will provide a new framework for understanding the structural and tectonic origins of a significant part of the western Caribbean plate.

Publications
Papers in preparation:
Rogers, R., and Mann, P., Plate tectonic controls on two styles of active, transtensional deformation along the North America-Caribbean plate boundary zone.

Rogers, R., Mann, P., and Emmet, P., Late Cretaceous amalgamation of the western Caribbean plate by collision between the Chortis block and intraoceanic Caribbbean arc and oceanic plateau.

Rogers, R., Mann, P., and Scott, R., Cretaceous intra-arc rifting, sedimentation, and basin inversion in east-central Honduras.

Rogers, R., Mann, P., and Emmet, P., Tectonic terranes of the Chortis block (Honduras and Nicaragua) inferred from integration of regional aeromagnetic and geologic data.

Dissertation:
Rogers, R., 2003, Jurassic-Recent tectonic and stratigraphic history of the Chortis block of Honduras and Nicaragua (northern Central America): unpublished PhD dissertation, University of Texas at Austin, 264 p.

Journal articles:
Mann, P., Rogers, R., and Gahagan, L., Central American plate tectonic setting and remaining tectonic problems, in J. Bundschuh, editor, Central America: Geology, Resources, and Hazards, Balkema Publishing, in press.

Rogers, R., Karason, H., and van der Hilst, R., 2002, Epeirogenic uplift above a detached slab in northern Central America: Geology, v. 30, p. 1031-1034.