Sign up & Download
Sign in

Analisis de biofacies y cambios relativos del nivel del mar en el Miembro Pilmatue de la Formacion Agrio, Cretacico Inferior de cuenca Neuquina, Argentina

by D G Lazo
Ameghiniana ()

Abstract

A biofacies analysis based on benthic macrofossils was carried out. The study unit is the Pilmatue? Member of the Agrio Formation in three sections in the Neuque?n Province. Six biofacies controlled by relative sea level changes, sedimentation rate, substrate consistency, oxygenation and salinity were recognised. The "Cucullaea-Mimachlamys-Steinmanella biofacies" is highly diverse and recorded in a shoreface environment characterized by a well-oxygenated soft sandy and patchy bioclastic substrate, reduced siliciclastic input, normal marine salinity, and warm-temperate waters. The "coral colonies biofacies" is associated with the former biofacies, but in a more shallow setting and probably temperatures above 16_-18_ C The "Cucullaea and Steinmanella biofacies" occurred in an open shelf environment characterized by low water energy, reduced siliciclastic input, firm muddy substrate, and normal marine conditions. The "Modiolus biofacies" also occurs on the shelf, but under low oxygenation. The "gregarious serpulids" and "gregarious oysters" biofacies correspond to an inner shelf setting characterized by an alternation of high and low water energy, low siliciclastic input, firm muddy substrate, well-oxygenated bottom, and mixo-euharine conditions. The "Cucullaea-Mimachlamys-Panopea" and "Cucullaea and Steinmanella" biofacies are related to changes of relative sea level in the scale of parasequences, while the "coral colonies", "Modiolus", "gregarious oysters", and "gregarious serpulids" respond to changes in the scale of sequences. _Asociacio?n Paleontolo?gica Argentina.

Cite this document (BETA)

Readership Statistics

5 Readers on Mendeley
by Discipline
 
by Academic Status
 
60% Researcher (at an Academic Institution)
 
20% Post Doc
 
20% Ph.D. Student
by Country
 
60% Argentina

Sign up today - FREE

Mendeley saves you time finding and organizing research. Learn more

  • All your research in one place
  • Add and import papers easily
  • Access it anywhere, anytime

Start using Mendeley in seconds!

Already have an account? Sign in