Houston Geological Society

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HGS Academic Liaison Presentation Archives
Extreme Paleocene - Eocene Sea Level
Fluctuation(s) in the Gulf of Mexico A
Hypothesis Part IIIc Effects of
Re-connection Josh Rosenfeld and Jim Pindell
Cerro Azul 4 blow-out, Veracruz, Mexico
February 1916
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Sierra de Chiapas El Bosque Fm.
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Eocene Unconformity - Veracruz Foldbelt
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Sierra de Chiapas El Bosque Fm.
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Sierra de Chiapas El Bosque Fm.
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Sierra de Chiapas El Bosque Fm.
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What about Eocene salt (?)

• NaCl in sea water 35,000 ppm by weight.

• Evaporation gt 90 required to precipitate salt.
• (carbonates/gypsum volumetrically minor)

• Total evaporation of a 3000 meter seawater
• column yields 48 meters of halite. Thick salt
• deposits require renewed seawater influx.

• It is unlikely that salt accumulated, except
  perhaps in the central Gulf.

• Any thin salt deposits would have been subject
• to dissolution upon refilling of Gulf.

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Lower Tertiary Source Rocks
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Lower Tertiary Source Rocks in Point Coupe and
St Landry Parishes, LA
Data From Sassen and Chinn, 1990
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Lower Tertiary Source Rocks in the Amoco MC-84
Well
Depth TOC HI Amorph. Ker. 14,645 3.05 541 6
0 14,650 2.69 468 60 14,810 3.30 536 90
Hyper-saline or Condensed Section??
From Wagner, Sofer and Claxton, 1994
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Some Conclusions

• There was at least one major G.O.M. drawdown in
  the Early Eocene.

• There is a large paleocanyon under the
• Rio Grande in the Vicksburg Embayment.

• Wilcox sands should be widespread
• in the deep Gulf(Deltaic? Neritic?)

• Everyone is invited to play!!!