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The olistostromes formed in Northern Carpathians during the different stages of the development of flysch basins, from rift trough post-

Abstract:In southern Poland, Miocene deposits have been recognised both in the Outer Carpathians and the Carpathian Foredeep (PCF). In the Outer Carpathians, the Early Miocene deposits represent the youngest part of the flysch sequence, while in the Polish Carpathian Foredeep they are developed on the basement platform. The inner foredeep (beneath the Carpathians) is composed of Early to Middle Miocene deposits, while the outer foredeep is filled up with the Middle Miocene (Badenian and Sarmatian) strata, up to 3,000 m thick. The Early Miocene strata are mainly terrestrial in origin, whereas the Badenian and Sarmatian strata are marine. The Carpathian Foredeep developed as a peripheral foreland basin related to the moving Carpathian front. The main episodes of intensive subsidence in the PCF correspond to the period of progressive emplacement of the Western Carpathians onto the foreland plate. The important driving force of tectonic subsidence was the emplacement of the nappe load related to subduction roll-back. During that time the loading effect of the thickening of the Carpathian accretionary wedge on the foreland plate increased and was followed by progressive acceleration of total subsidence. The mean rate of the Carpathian overthrusting, and north to north-east migration of the axes of depocentres reached 12 mm/yr at that time. During the Late Badenian-Sarmatian, the rate of advance of the Carpathian accretionary wedge was lower than that of pinch-out migration and, as a result, the basin widened. The Miocene convergence of the Carpathian wedge resulted in the migration of depocentres and onlap of successively younger deposits onto the foreland plate.

Sev eral sec tions re cord the re la tion be tween the "black flysch" and Up per Cre ta ceous red shales in the Grajcarek thrust-sheets. In all the sec tions stud ied the "black flysch" ap pears in the core of imbricated folds or thrust-sheets, whereas the limbs are com posed of Up per Creta ceous de pos its. The tran si tional beds be tween the " black flysch" and the Up per Cre ta ceous red shales are com posed of green and black bi tu mi nous shales, green and red radiolarites and cherty lime stones. Biostratigraphical in ves ti ga tions have re vealed a sim i lar type and sequence of micro fauna as sem blages in all the sec tions stud ied and sig nif i cant redeposition of Ju ras sic cal car e ous ben thic foraminifera, cal car e ous nannoplankton, molluscs, sponge spicules and cri noid el e ments. The Cre ta ceous age (Aptian/Alb ian-?Cenomanian) of the "black flysch" is shown by the pres ence of ag glu ti nated foraminifera and microfacies data. These de pos its are un der lain by a Kimmeridgian-Aptian radiolarite/lime stone con densed suc ces sion and over lain by Turonian-Campanian hemipelagic red shales and Maastrichtian/Lower Paleocene con glom er ates and thick-bed ded silicilastic turbidites of the Jarmuta For ma tion. Such a se quence of depos its is typ i cal of the Outer Carpathian bas ins and re cords the global Mid/Late Cre ta ceous phe nom ena in the world ocean, fol lowed by the Cre ta ceous Oce anic Red Beds. Nestor Oszczypko and Ewa Malata, In sti tute of Geo log i cal Sci ences, Jagiellonian Uni ver sity,