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Investigations of fossil algae in Croatia began in 1907 with the very first description of the Permian dasyclad Mizzia velebitana from Mt. Velebit by Austrian geologist Richard Schubert. This was followed by Julius Pia's investigations (1920, 1925), on material given to him by Schubert. The first Croatian researcher on fossil algae was Milan Herak, Pia's PhD student, with his first paper on Ladinian dasyclads published in 1950. He cooperated with a colleague from the Faculty of Science, Vanda Kochansky-Devidé, who published her first papers together with Herak on Permian and Carboniferous dasyclads in 1959 and 1960. While Herak focused on Triassic algae, Kochansky-Devidé investigated mostly Upper Palaeozoic algae and fusulinid foraminifera. Ivan Gušić comes from the same faculty, and his first paper was published in 1966. Momčilo Milanović, from the Institute of Geology (the present day Croatian Geological Survey), published his first paper in 1962, focusing mainly on Permian algae. The most prolific researcher Branko Sokač also came from the Institute of Geology; his first papers dated from 1964, and he is still an active researcher. Over time, papers originating from the "Zagreb Algological School" become distinguished by rich and well illustrated fossil material, making numerous contributions to the better understanding of fossil benthic algae from younger Palaeozoic and Mesozoic strata. This was possible not only because of the diligence of the authors, but was also the result of the very thick and well exposed carbonate sequence of the Croatian Dinarides Mts. Rajka Radoičić from Beograd (Serbia) also described some taxa from Croatia. Almost all the research refers to dasycladal algae, while other algae are only rarely investigated. Complete references to all papers are given. [ABSTRACT FROM AUTHOR]

Early-intracontinental rifting of Pangea was a result of thermal doming in Uppermost Permian time giving rise to the formation of horst-graben structures, followed by slow subsidence, marine transgression and evaporite deposition. The consequences of incipient magmatism and a high heat flow are numerous geothermal fields and subterrestrial hydrothermal siderite-barite-polysulfide deposits (PALINKAŠ et al., 2016). Advanced rifting magmatism as a successive stage in the Middle Triassic brought intensive submarine volcanism, accompanied by coeval sedimentation of chert and siliciclastics, building up volcanogenic-sedimentary formations. Volcanic activity with explosive phases and the generation of large volumes of pyroclastic rocks in the rifts produced concomitant mineralization with numerous sedimentary exhalative (SEDEX) deposits of Fe-Mn-Ba-polysulfides. The passive continental margin of northern Gondwanaland is flanked by the AdriaDinaridic carbonate platfom, while the Moesian carbonate platform is a counterpart on the European passive continental margin. They were divergently drifted in the course of the advanced rifting. A fast growing carbonate platform, developing gradually, covered evidence of the earlier intracontinental rifting and their ore formations. However, the carbonate platforms themselves host specific Pb-Zn deposits, well known as a Mississippi valley type, (MVT) or Bleiberg-Mežica type according the traditional european terminology. Triassic MVT and SEDEX deposits are symmetrically situated on the both sides of the divergent passive margins in this early history of the Tethyan ocean. The paper gives a brief description of the MVT and SEDEX deposits, in the two carbonate platforms and rifts in between, formed synchronously and in a similar manner on opposing sides of the diverging continental margin. [ABSTRACT FROM AUTHOR]

The present paper compiles an up-to-date taxonomic inventory of dasycladalean green algae of the Kimmeridgian-Early Berriasian Plassen Carbonate Platform and their resediments in basinal sediments (e.g., Barmstein Limestone, Sillenkopf Formation) of the Northern Calcareous Alps of Austria (p.p. Germany). Today, the Plassen Carbonate Platform sensu lato (or Plassen Group) is divided into three independent carbonate platforms with radiolarite deep-water basins between: the Wolfgangsee Carbonate Platform to the north, the Plassen Carbonate Platform sensu stricto in a central position and the Lärchberg Carbonate Platform to the south. All together 42 taxa are reported from these platforms and associated resediments, each shortly commented and illustrated. Amongst these, there are taxa common in all three platforms, others exhibit restricted distributions. These peculiarities can be explained by the different lithostratigraphic and overall geodynamic evolution of the three platforms. In many cases, it allows the assignment of resediments in basinal series to a certain platform as a helpful palaeobiogeographical tool when other data are lacking. [ABSTRACT FROM AUTHOR]

A study of calcareous strata previously assigned to the Barremian-Early Aptian interval in the northwestern part of Pădurea Craiului, (Apuseni Mountains), led to the identification of a micropaleontological association indicative of a Late Aptian age. Unequivocal evidence for the Late Aptian assignment of these limestones is the presence throughout the sequence of two orbitolinid species, Mesorbitolina texana (ROEMER) and Mesorbitolina subconcava (LEYMERIE). The most interesting sections are located in the neighbourhood of Subpiatra, where both outcrops and a quarry facilitated detailed analyses. In this area, the Upper Aptian succession consists basically of three types of macrofacies: 1) limestone with rudists; 2) limestone with Bacinella and 3) limestone with corals, each of them showing several types of microfacies. Bacinella structures are the most common feature in the whole succession, irrespective of the macrofacies. This paper focuses on an algal association that was identified in several levels within the succession. Dasycladalean algae are more frequent, and are commonly found in grain-dominated fabrics (mostly grainstone textures), in association with orbitolinid foraminifera and bioclasts of corals, rudists and gastropods. However, a few species are present only in mud-dominated fabrics (i.e. lower-energy intervals). The dasycladalean association from the Upper Aptian deposits of Padurea Craiului is of special interest, for this group registered a dramatic decline at the Lower Aptian/Upper Aptian boundary, as confirmed by the relative scarcity of the Dasycladales in the Upper Aptian carbonate deposits. [ABSTRACT FROM AUTHOR]