2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM

Paper No. 1
Presentation Time: 8:05 AM

Structural Diagenesis: An integrated investigative approach to coupled chemical and mechanical processes in sedimentary systems


LAUBACH, Stephen E., Bureau of Economic Geology, The University of Texas at Austin, University Station, Box X, Austin, TX 78713, steve.laubach@beg.utexas.edu

Structural diagenesis is a new perspective for understanding how fracturing, fault growth, compaction, and other mechanical processes interact with chemical processes to govern the attributes of structures and physical properties of sedimentary rocks at high crustal levels in the Earth. Although clearly a characteristic part of the postdepositional changes that affect rock, fractures and faults are commonly neglected in conventional diagenetic studies, which thus miss an essential aspect of the transformation of sediment into rock. Likewise, structural studies, at least those concerned with the low-temperature realm of sedimentary basins, tend to focus on geometry, kinematics, and mechanics. Thermal controls and chemical processes are commonly ascribed limited importance, if considered at all. Yet much can be learned about chemical diagenesis by reference to structure, and vice versa, and chemical and mechanical processes may be coupled in many ways. There are undoubtedly some important feedbacks between them. Cross-disciplinary research is beginning to address some of these issues, but systematic student training in principles of both structure and diagenesis is the key to unlocking scientific knowledge about a part of the Earth's interior that is of great intrinsic and practical interest. These challenges call for a merger of disciplines and a new training paradigm in sedimentary geochemistry and structural geology.