At the end of Pliensbachian or during the Toarcian, several carbonate platforms were individualised by extensional tectonics in southern Tethys, of which the Adriatic Carbonate Platform is one. As a unique and isolated shallow marine depositional system it existed until the end of the Cretaceous. In the Late Lias, the platform margins and slopes were formed by the individualisation processes. Due to the presence of younger sedimentary cover and tectonic disruption from the Early Jurassic until the present, only small parts of the north-easternmargin and its slope are exposed at the surface.During the entire “life-span” of the platform, its NE margin and slope retained more or less the same palaeogeographic position – from western to south-eastern Slovenia, through the central part of Croatia, western and central Bosnia, northern Herzegovina and Montenegro all the way to northern Albania. The region between Žumberak in Croatia and central Bosnia was the most dynamic part of the platform margin during the Jurassic and Cretaceous. Shifts of the marginal and slope facies were recorded in Žumberak, where the platform area wasp rogressively reduced during the period from the Lias to the Malm. At the same time, the platform was extended in central Bosnia and Montenegro. A more pronounced reduction of the platform in Cenomanian times marked the beginning of the process of disintegration. The end of the Cretaceous was also the end of the “life” of the Adriatic Carbonate Platform. It mostly became emergent, and the renewed shallow marine carbonate depositional environments in the Eocenewere short-lived and lacked the previous platform characteristics, aswell as the regional distribution and integrity.
There is today a general unawareness of the fact that the technique of culturing plant tissues and organs under axenic conditions was first established and profitably employed in bryophytes, especially mosses (S e r vet t a z 1913). However, despite such a promising start, bryophytes did not retain for long their rightful place as highly favored research objects, so that most studies of plant morphogenesis are now being done on vascular plants. Apart from the favorable economic aspect, of experimenting on bryophytes, many fundamental and applicative physiological, genetic, morphogenetic, evolutionary and other problems can be tackled more easily by using bryophytes than vascular plants. Bryophytes are the second largest group of higher plants after flowering plants [Magnoliopsiday; with approximately 28.000 species found worldwide. However, most bryophyte species have no commercial value, and are therefore less attractive in a wide range of studies. Some 40% of these tiny species are endangered at present and in urgent need of active protection and conservation. Despite a long history of growing bryophytes in culture and the existing of different-sized collections maintained by some investigators, any newcomer wishing to start their cultures faces a stiff challenge (S a r g e n t 1988). One of the latest ideas is to establish sterile in vitro cultures, then micropropagate plants and later consider methods of their reintroduction into potential native habitats. The first relevant steps in Yugoslavia have already been made and are presented in this communication. Bryum argenteum Hedw. and Bryum capillare Hedw. (Bryaceae) were chosen for this experiment as they are unendangered cosmopolitan species and a model system for further in vitro investigation of mosses. These species are easily accessible because their habitats include urban and suburban areas. Bryum argenteum Hedw. is quite frequent while Bryum capillare Hedw is sporadic. The plants grow up to 5 mm in height and in the form of very small cushions. Reproduction of these species is mostly vegetative, although both are known to produce gametangias. In Bryum capillare Hedw., sporphytes are not usually seen, while in Bryum argenteum Hedw. they are quite rare (S
In spite of the high level of petroleum-geological exploration of the Croatian part of the Pannonian basin, areas still exist that are worth paying attention to because of favorable lithostratigraphic and tectonic relations. Such is the area of the Slavonian Mts. (Mt. Papuk, Mt. Krndija, Mt. Psunj, Mt. Pozeska Gora and Mt. Dill Gora) and their immediate surroundings (parts of the Drava and Sava basins and the Pozega basin). Due to their secondary porosity, the Triassic dolomite-limestone sediments are potential geothermal aquifers. These rocks were also the source of sedimentary material for a well-known type of reservoir rock -Early Neogene carbonate breccia that is the lateral equivalent of basinal clastics. The Neogene mostly clastic sediments, that are regionally known to form oil and gas reservoirs, are found under the overthrusted older rocks, making these relations favorable for oil and gas entrapment. The mentioned conclusions are based on tectonic framework of the study area, paleogeographic reconstruction of sedimentary basins with comparison of their recent widths and on analyses of thickness of the Neogene sedimentary sequences.
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