Sandbox Modeling of Continent-Continent Type Collisions with Underlying Basement Structures
Department
Geosciences and Geological and Petroleum Engineering
Major
Geology and Geophysics
Research Advisor
Hogan, John Patrick
Advisor's Department
Geosciences and Geological and Petroleum Engineering
Funding Source
Geological Sciences and Engineering
Abstract
When continents collide, the earth’s crust shortens and thickens by thrust faulting in a mountain building event. We investigated the effect of preexisting basement structures (old faults) on development of thrust faults in the cover rocks during collision using a “sandbox” with clear sides and a movable wall. Alternating beds of colored sand representing sedimentary cover rocks were layered over rigid wood blocks representing igneous/metamorphic basement rocks. The wooden blocks included 30° cuts to emulate preexisting basement faults. The moveable wall was used to horizontally shorten the model and imitate continent-continent collision. Reactivation of basement faults initiated faults in the cover that localized the strain in the growing wedge. The angles and spacing of pre-existing basement structures were seen to directly control thrust fault propagation in the “cover rocks” as well as the wedge thickness (i.e., height of the mountain range) of the system as it was compressed.
Biography
Gina Callaway is a Missouri native from Jefferson City. She transferred to Missouri S&T in the summer of 2006. She became a Geology and Geophysics major late in fall 2006. She will graduate in May 2009 with her bachelor of science and begin work in late summer with Southwest Energy in Fayetville, Arkansas.
Research Category
Sciences
Presentation Type
Poster Presentation
Document Type
Poster
Location
Upper Atrium/Hallway
Presentation Date
08 Apr 2009, 9:00 am - 11:45 am
Sandbox Modeling of Continent-Continent Type Collisions with Underlying Basement Structures
Upper Atrium/Hallway
When continents collide, the earth’s crust shortens and thickens by thrust faulting in a mountain building event. We investigated the effect of preexisting basement structures (old faults) on development of thrust faults in the cover rocks during collision using a “sandbox” with clear sides and a movable wall. Alternating beds of colored sand representing sedimentary cover rocks were layered over rigid wood blocks representing igneous/metamorphic basement rocks. The wooden blocks included 30° cuts to emulate preexisting basement faults. The moveable wall was used to horizontally shorten the model and imitate continent-continent collision. Reactivation of basement faults initiated faults in the cover that localized the strain in the growing wedge. The angles and spacing of pre-existing basement structures were seen to directly control thrust fault propagation in the “cover rocks” as well as the wedge thickness (i.e., height of the mountain range) of the system as it was compressed.
Comments
Joint project with Mark Dunseith