The Kamień Pomorski IG-1 borehole (Pomerania, NW Poland) yields a profile through the Triassic-Jurassic (T-J) transition in continental deposits. An integrated study of the sedimentology, sequence stratigraphy, palynology, biostratigraphy and geochemistry of these deposits has been carried out on the boundary interval, which represents a time of major environmental change. Two lithological units within the transitional section are distinguished: the Lower-Middle Rhaetian Wielichowo Beds of alluvial plain facies, which shows evidence of a semi-arid climate, and the Upper Rhaetian to Lower Hettangian Zagaje Formation, lying above a marked erosional sequence boundary, composed of mudstone-claystone and sandstone deposited in a fluvial-lacustrine environment. Carbon isotope values obtained from palynomaceral separates, and thus reflecting isotopic changes in atmospheric CO 2 , show significant fluctuations through the Rhaetian; the most conspicuous negative δ 13 C org excursion is correlated with the Rhaetian 'initial' excursion and shows two sub-peaks, pointing to short-term carbon-cycle disturbances of lesser magnitude. Above the 'initial' negative excursion, there is a positive excursion followed again by more negative values, representing subordinate fluctuation within a positive excursion and is correlated with the T-J boundary. Seventy-two miospore taxa have been determined from the studied T-J transitional section. Two major palynological assemblages have been distinguished: the lower one, typically Rhaetian, named the Cingulizonates rhaeticus-Limbosporites lundblandii association, which corresponds to the Rhaetipollis-Ricciisporites (= Rhaetipollis-Limbosporites) Zone; and the upper one, typically Hettangian, named the Conbaculatisporites mesozoicus-Dictyophyllidites mortoni-Cerebropollenites thiergartii association (with the age-diagnostic pollen C. thiergartii), which corresponds to the Pinuspollenites-Trachysporites (= Trachysporites-Heliosporites) Zone. The T-J palynofloral turnover occurred in a humid period and is more conspicuous then palynofloral changes observed in Greenland, the Tethyan domain or other parts of NE Europe. The osmium isotope system is studied herein for the first time from T-J continental deposits and shows marked disturbances similar to those measured in marine deposits and attributed to volcanic fallout. Carbon and osmium isotope correlation and coeval increase in polycyclic aromatic hydrocarbon (PAH) content and darkening of miospores confirm that eruptions of the Central Atlantic Magmatic Province (CAMP) contributed to the perturbances in climate and crisis in the terrestrial biosphere. A series of periodical atmospheric loading by CO 2 , CH 4 or alternatively by SO 2 , sulphate aerosols and toxic compounds is inferred to have caused a series of rapid climatic reversals, directly influencing the ecosystem and causing the Triassic floral crisis. A floral turnover period commenced at the 'initial' δ 13 C excursion, with the onset of CAMP volcanism. Obtained values of initial 187 Os...

palynofacies inversions (abnormal palynofacies composition) are discussed. Six main palynofacies types linked to depositional systems previously determined by sedimentological studies have been distinguished providing a robust paleoenvironmental tool for recognition of palynofacies attributed to certain palaeoenvironments.

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Sed i men tary en vi ron ments and palynofacies were iden ti fied in the Lower Cre ta ceous of cen tral Po land. The study was based on lithological ob ser va tions, sedimentological log ging and palynological in ves ti ga tions in eleven bore holes. Palynological ob ser va tions in cluded pri mar ily iden ti fi ca tion of the pro por tions, vari abil ity and fea tures of in di vid ual com ponents of palynological mat ter. The re sults were cor re lated with sedimentological, lithofacies and palaeo geo graphi cal data. Sed i men tary en vi ron ments and palynofacies were ana lysed in the ver ti cal sec tion, and spa tially in dif fer ent ar eas: in the central ba sin area, in the car bon ate-clastic de po si tion zone, in the tran si tional zone (deltaic sed i men ta tion) and in a zone of an ac tive salt pil low. The fol low ing sed i men tary en vi ron ments were iden ti fied in the Lower Cre ta ceous: up per shoreface and lower-mid dle shoreface with tran si tions to an off shore-open-ma rine shelf, delta (?delta front) pass ing up into distributary chan nel fills on a delta plain, pre sumed bar rier and shal low-ma rine embayment, la goon and shal low car bon ate-siliciclastic shelf. In case of the ab sence of di ag nos tic fea tures for ex act de ter mi na tion of sed i men tary en vi ron ments, they were de fined as gen er ally ma rine or tran si tional (prob a bly deltaic). A max i mum flood ing sur face has been iden ti fied in the Poddębice PIG 2 sec tion, rep re sented by a thin dark grey marl bed which is dated ap prox i mately at the Berriasian/Lower Valanginian tran si tion. The re la tion ships be tween sed i men tary en vi ron ments and the char ac ter is tics of the palynofacies spec trum were de ter mined, and a palynofacies pat tern for the Lower Cre ta ceous of cen tral Po land has been pro posed.Key words: Lower Cre ta ceous, cen tral Po land, palynomorphs, or ganic mat ter, sed i men tary en vi ron ments, palynofacies pat tern.

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