Chicontepec Field Seminar Itinerary
Day 1
Arrive in Tampico, Mexico. Flight from Houston arrives around 8:00 pm. Drive to hotel. Night in Tampico.
Day 2
Drive south from Tampico to Stop 1.
Stop 1
Observation of undeformed Chicontepec thick-bedded facies. Observe scour features, sedimentary structures (ripples, cross-bedding, parallel lamination, bioturbation, convolute bedding, flutes)
Lunch
Stop 2
Observation of undeformed thin-bedded and thick-bedded Chicontepec facies. Observe slump within low net/gross facies and sedimentary structures (sole marks, trace fossils, ripples).
Stop 3
Observe small syndepositional slump about 1 meter thick in thin-bedded turbidites. Discuss slump recognition criteria.
Stop 4
Observe thick, overturned Chicontepec section showing loading, flutes, syndepositional faulting and a preserved toe-of-thrust feature. Group exercise.
Day 3
Stop 5A
Syndepositional thrusts showing slumps originating at the "tip out" point. Slumps dissipate within 50 meters.
Drive to Stop 6, observing igneous dykes and truncation surfaces in thin-bedded turbidites.
Stop 6
Outcrop of undeformed thin-bedded turbidites and overlying slump, showing details of architecture at base of slump, including shear surfaces and multiple truncation surfaces. Example of a FAULTED SLUMP.
Stop 7
Outcrop of slump showing shear plane at base. Bed continuity very high within the slumped section. Example of a COHERENT SLUMP.
Lunch
Stop 8
Drive slowly past example of BOUDINAGED SLUMP. Outcrop shows base and top of large slump with flat-lying beds on top and pinchout of sandstones on top of slump surface. Discussion of recognition criteria and orientation of outcrops.
Stop 9
Extremely large slump outcrop showing onlap of several sandstone beds on top of slump, truncation surfaces and syn-depositional thrusts. Further discussion of recognition criteria. Example of COHERENT and SEMI-COHERENT SLUMP.
Stop 10
Observation of the base of the slump at stop 8. Estimation of thickness of slump.
Day 4
Stop 11
Outcrop across valley viewed by binoculars. View of thick-bedded, lenticular sandstones with a large slump on top.
Stop 12
Large road cut showing ramping up of base of slump and a large "flap" of stratigraphy folded at 90 degrees. Right side of outcrop shows preserved slump margin. Multiple truncation surfaces.
Stop 13
Large road cut showing undeformed thin-bedded turbidites above and below a slump. Slump shows variable deformation from coherent to uncoherent with shear planes. Example of COHERENT, SEMI-COHERENT SLUMP and DEBRIS FLOW.
Stop 13A
Road cut showing a CHAOTIC slump with a very sharp base.
Stop 14
Outcrop containing 26 m and 3 m thick DEBRIS FLOWS in the Chicontepec Formation. Top of thick debris flow shows pressure ridges with thin-bedded sandstones filling in the lows. Boulders float on top of the debris flow. Base of debris flow surface is erosional (not from debris flow) and dramatically cuts stratigraphy. Edge of debris flow shows syndepositional faults and preserved "flap" of stratigraphy. Many bed thickness changes also occur.
Day 5
Stop 15
Igneous sills and dikes in thin-bedded turbidites. Three sills are visible, much thicker and more porous than the thin-bedded sandstones. Walk down outcrop to view syndepositional thrusts.
Stop 16
Multiple scour surfaces in thin-bedded turbidites, creating bed thickness changes within a short lateral distance.
Stop 17
Thick, friable igneous sill with baked zones. Dark nodules within the sill contain magnetite, illite, calcite and plagioclase.
Stop 17A
Basin-margin thrust fault within Chicontepec Formation.
Lunch
Drive back to Tampico
Night in Tampico
Day 6
Depart Tampico. Houston flights leave early in morning.
