Palinología estadística en el Cretácico de la Cuenca Austral, Plataforma Continental Argentina. I. Seis perforaciones del área Magallanes

Abstract

A statistical study of palynomorph groups found in six offshore wells of the Magallanes area in the Austral Basin is here presented. All samples are sidewall cores. The following groups have been considered: E (pteridophytes and bryophytes), Ci (cicatricose spores), G (gleicheniaceous spores), C (Classopollis), Ca (Callialasporites), P (other Podocarpaceae), Pt (pteridosperms of the Vitreisporites type and monocolpate pollen grains of cycadophyta and/or ginkgophyta), Cy (Cyclusphaera, Balmeiopsis & Araucariacites) and A (angiosperms). A separate count was devoted to marine vs. continental palynomorphs (C/M) and the pterophytes/ gymnosperms/angiosperms relationship (H/G/A). Percentages of each group are presented for all six wells, and their significance analyzed. A correlation of the lower sections of most wells with the Early Cretaceous Springhill Formation and the Baqueró Group of southern Argentina and Chile is suggested. One well (MFJ-8) cuts strata of Late Cretaceous age as suggested by the finding of known microplankton taxa that were mentioned elsewhere.