GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 271-12
Presentation Time: 9:00 AM-6:30 PM


KONDAS, Marcelina, Faculty of Earth Sciences, University of Silesia in Katowice, Będzińska 60, Sosnowiec, 41-200, Poland

The palynological investigation has been carried out on the samples collected from the Zaręby IG-2 borehole (western Holy Cross Mts., Poland). The analyzed section comprised of limestone interbedded with dolomites and single layers of mudstones. All samples contained well preserved palynomorphs assemblage including miospores, phytoclasts, algae and zoomorphs. Moreover, all samples were strongly dominated by amorphous organic matter (AOM).

Based on the miospore assemblage, the age of the investigated samples was tentatively established as VI-HD Miospore Zone (Vallatisporites verrucosus – Retusotriletes incohatus and Kraeuselisporites hibernicus – Umbonatisporites distinctus zones).

The palynofacies analysis has been done as well. Land derived material strongly prevailed marine components. The presence of prasinophytes and very limited number of acritarchs might indicate low-oxygen conditions. This diagnosis was supported by occurrence of AOM.

Within the observed section phytoclasts assemblages were dominated by the dark-brown-pale brown remains, with sharp outline and high angularity. This indicates a relatively short transport of the material and high rate of sedimentation. The ratio of equant and lath-shaped phytoclasts might suggest the deposition relatively close to the terrestrial source area. Almost all of the observed phytoclasts were not degraded.

Taking into account the proportions of various components, the depositional environment may be determined as sub-oxic-anoxic, shallow shelf.

This project was financially supported by NCN grant nr 2017/27/N/ST10/01699 to M. Kondas, (University of Silesia, Poland).