Document Type
Dissertation
Degree
Doctor of Philosophy
Department
Geosciences
Advisor's Name
Dr. Florentin J.M-R. Maurrasse
Advisor's Title
Committee Chair
Advisor's Name
Dr. Fernado Etayo-Serna
Advisor's Title
Committee Member
Advisor's Name
Dr. Jose Guadalupe Lopez Oliva
Advisor's Title
Committee Member
Advisor's Name
Dr. Rosemary Hickey-Vargas
Advisor's Title
Committee Member
Keywords
Geochemistry, Cyanobacteria, Cenomanian/Turonian, Black shales, clyclestratigraphy
Date of Defense
6-2-2006
Abstract
High-resolution lithostratigraphic data from rock sequences known as the Indidura Formation near Parras de La Fuente, Coahuila, NE Mexico, led to achieve a significant improvement of our knowledge of that Formation. The results of this study indicate for the first time that the sequence at Parras de La Fuente developed from the deposition of calcareous cyanobacterial microspheroids that accumulated under perennial blooms during the Late Cenomanian through the Middle Turonian.
Multi-proxy analyses included sedimentological, petrographical, scanning electron microscopy, stable isotope, trace element geochemistry, and paleontological data. The combined results allowed the correlation of δ13C and anomalies in Mo, V, and Cr with the abundance and predominance of calcareous cyanobacterial microspheroids, which were the main suppliers of the carbonate components and the organic matter throughout deposition of the Indidura Formation in the Parras de la Fuente area, under dysoxic/anoxic conditions.
Conspicuous interbeds of dark and light-gray laminated marly calcilutites, and dark-gray marlstones that characterize the stratigraphic sequence formed in response to external forcing climatic factors of millennial-scale Milankovitch cycles (ca. 20 ka precession). At the microscopic level, the prominent dark and light-gray laminae were formed during cycles similar to the 10 to 15 years solar irradiance maximum, and represent alternating periods of high and low calcareous cyanobacterial microspheroids productivity.
Recommended Citation
Duque-Botero, Fabian, "Paleoenvironmental Implications of the Indidura Formation (Cenomanian/Turonian), Northeastern Mexico: a High Resolution Stratigraphic Study" (2006). FIU Electronic Theses and Dissertations. Paper 46.
http://digitalcommons.fiu.edu/etd/46