Daniel ȚABĂRĂ
„Al. I. Cuza” University of Iaşi, Department of Geology, 20A Carol I Blv., 700505 Iaşi, Romania. E-mail: dan.tabara@yahoo.com

PALYNOLOGY, PALYNOFACIES AND ORGANIC GEOCHEMISTRY ON THE LOWER CRETACEOUS SUCCESSION (AUDIA FORMATION) FROM EASTERN CARPATHIANS, ROMANIA

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This study focused on the Cretaceous black shale from Audia Formation which cropping out in the Eastern Carpathians. This is multidisciplinary approach to the study of some samples from these formation, supported by organic petrography (palynofacies, Thermal Alteration Index – TAI, fluorescence) and organic geochemistry (Total Organic Carbon – TOC). The palynofacies analysis provides evidence that the organic matter is composed of particles belonging to the amorphous organic matter group (in the middle part of the Lower Member) and opaque/translucent phytoclasts which are more numerous in the upper part of Lower Member and the Middle Member of Audia Formation. The palynological assemblage consists of dinoflagellates cysts, some with biostratigraphic importance, and continental palynomorphs such as ferns, Bryophyta and gymnosperms. The TOC data confirm that the samples have a good to very good petroleum potential, and can generate particularly wet gas, condensate or thermogenic gas, and less oil. Type III kerogen is predominant in the samples analyzed, and can be considered thermally mature (in the oil window) based on TAI values and the fluorescence of organic matter.