GCAGS 2007 Field Trips

 

 

Field Trip #1

Coastal Geology and its relationship to ground water.

Leaders:  Richard Hay, Jennifer Smith-Engle, and Egon Weber, Texas A&M University – Corpus Christi.

Date:  October 20, 2007 (Saturday).

Depart:  Meet at GCAGS Convention Facilities 7:30AM for 8:00AM departure.

Return:  GCAGS Convention Facilities no later than 5:30 PM.

Tuition:  $25/person.  Includes guidebook and transportation.  A complimentary lunch will be provided.

Enrollment:  Minimum 10, Maximum 25.

Who should attend:

     This field trip will be of interest to ground water, environmental, and coastal geologists and geophysicists.

 Objectives:

     Observe and discuss the Gulf Coast aquifer system and coastal hydrogeology in the semi-arid setting of South Texas.  During this field trip we will observe coastal flood plains, secure landfill, coastal faulting, sabkhas (wind tidal flats) and barrier islands.  Discussions will include surface/ground water interactions, subsidence, desalination, aquifer storage and recovery (ASR), barrier island hydrogeology, sabkhas, and coastal development.

Field Trip - Coastal Geology and Ground Water.doc

 

 

Field Trip #2

SEDIMENTOLOGY, NEOICHNOLOGY, AND PRESERVATION POTENTIAL OF MODERN CLASTIC SHORELINE DEPOSITIONAL FACIES, MUSTANG AND PADRE ISLANDS AND NUECES INCISED-VALLEY ESTUARY

Leaders:  James R. Garrison, Jr., Texas A&M University-Corpus Christi, Corpus Christi, Texas and Bo Henk, Matador Resources, Dallas, Texas

Date: October 24-25, 2007

Location:  Begins and ends in Corpus Christi, Texas (Field trip will depart 8:00 AM and return to the GCAGS Convention Facility by 5:30 PM)

Tuition:  $75 includes guidebook, transportation by van and boat during the course, and all lunches during the field trip.

Enrollment:  Minimum 10, Maximum: 20

Who Should Attend:

     Exploration and production/reservoir geologists, environmental geologists, geophysicists, and engineers working ancient or modern clastic shoreline systems that need to understand the sedimentological and ichnological processes of clastic shoreline depositional systems and what their preservation potentials are. Understanding the preservation potential of depositional and ichnological facies facilitates the construction of more realistic depositional, paleoenvironmental, paleoecological, and geological reservoir models.

 Course Approach, Content, and Objectives

     This is a two-day field trip to the modern clastic shoreline depositional systems of Mustang and North Padre Islands and Corpus Christi and Nueces Bays.  Day 1 will focus on the development of beach and barrier island systems and the processes that affect them.  Day 2 will focus on the effects of sea-level rises and falls on the preservation potential of these coastal depositional systems.

The utility of geometric, architectural, sedimentological, ichnological, ecological, and facies data from modern clastic shoreline depositional systems in the development of analogs for ancient rock systems in outcrop or in the subsurface is a direct function of the preservation potential of modern depositional facies.  Not all primary depositional facies and ichnofacies within a depositional system are preserved in the rock record. 

When examining modern depositional systems, in the quest for an analog for a subsurface clastic shoreline system, geologists must evaluate what facies are most likely to be preserved and whether a missing facies necessarily mean that models must be revised. Therefore, an examination of the preservation potential of the individual facies of modern clastic depositional systems is warranted. 

It has been qualitatively documented that bioturbation destroys primary depositional fabrics, thus leading to incomplete preservation of many of the sedimentological structures used to make facies interpretations.  The ecology of burrowing and trace-making organisms can provide additional useful information for interpreting depositional facies.  In addition, bioturbation can either enhance or diminish reservoir quality.  Therefore, understanding neoichnology of modern coastal depositional systems is essential to developing subsurface models and evaluating reservoir quality.   

 Course set up:

Day 1 – A field examination will be made of the sedimentology and neoichnology the modern beach and barrier island, modern back barrier, abandoned flood tidal delta depositional systems along North Padre Island and Mustang Island, accompanied by lectures about the preservation and recognition of these facies in the ancient rock record.

Day 2 – A field examination will be made of the sedimentology, stratigraphy, and neoichnology of lowstand and transgressive systems tract estuarine depositional systems of the Nueces Incised Valley within Corpus Christi and Nueces Bays, accompanied by lectures about the preservation and recognition of these facies in the ancient rock record.  A field examination of the stranded Ingleside highstand barrier system at Flour Bluff and Oso Bay will be made to illustrate preservation scenarios of barrier islands subjected to sea-level fluctuations.

Principal objectives:

 • To be able to understand modern clastic shoreline depositional systems and the ecological systems associated with them.

 • To be able to identify and delineate the architecture of clastic shoreline deposits utilizing logs and cores.

 • To be able to identify ichnofossils and utilize them as paleoenvironmental and depositional facies indicators.

 • To obtain an understanding of concepts of preservation potential of clastic shoreline systems and how to condition modern analog data sets for application to subsurface reservoir systems.

Please note that some of the field trip stops involve some moderate walking.   At selected stops, field trip participants will be required to wade into the shoreface surf zone or into lagoonal or bay waters.  In addition, there will be travel by boats to selected field trip stops.  Sub-tropical weather in the field trip area is generally very warm and sunny; therefore precautions should be taken to minimize the effects of sun and heat.

 Field Trip - Modern Shoreline Depositional Systems.doc