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Mts. Kalnik and Požeška gora volcaniclastic sequences hold valuable information concerning the Miocene syn-rift evolution of the North Croatian Basin, and the evolution of the Carpathian–Pannonian Region and the Central Paratethys. We present volcanological, high-precision geochronological, and compositional data of volcanic glass to constrain their tephrochronology, magmatic provenance, and timing of the initial Central Paratethys flooding of the North Croatian Basin. Based on CA-ID-TIMS U–Pb zircon ages (18.060 ± 0.023 Ma for Mt. Kalnik and 15.345 ± 0.020 Ma for Mt. Požeška gora) and coeval 40Ar/39Ar sanidine ages (18.14 ± 0.38 Ma and 18.25 ± 0.38 Ma for Mt. Kalnik and 15.34 ± 0.32 Ma and 15.43 ± 0.32 Ma for Mt. Požeška gora), Mt. Kalnik rhyolitic massive ignimbrites and Mt. Požeška gora rhyolitic primary volcaniclastic turbidites are coeval with Carpathian–Pannonian Region Miocene post-collisional silicic volcanism, which was caused by lithospheric thinning of the Pannonian Basin. Their affiliation to Carpathian–Pannonian Region magmatic activity is supported by their subduction-related geochemical signatures. Although Mts. Kalnik and Požeška gora volcaniclastics are coeval with the Bükkalja Volcanic Field Csv-2 rhyolitic ignimbrites, North Alpine Foreland Basin, Styrian Basin, Vienna Basin, and Dinaride Lake System bentonites and volcaniclastic deposits, reliable tephrochronological interpretations based on comparison of volcanic glass geochemical composition are not possible due to a lack of data and/or methodological discrepancies. Our new high-precision geochronology data prove that the initial Middle Miocene (Badenian) marine flooding of parts of the North Croatian Basin occurred at least ~ 0.35 Ma (during the NN4 Zone) before the generally accepted ~ 15 Ma maximum flooding age at the basin scale, calibrating the timing of the onset of the widespread “mid-Langhian” Central Paratethys flooding.

The low-grade metasedimentary rocks of Medvednica Mt. (Northwest Croatia) are associated with ortho-greenschists (metabasalts). The Lower to Upper Triassic age of the protolith of the low-grade metamorphic rocks belonging to the Stari Potok, Adolfovac, Tusti Breg, Bliznec, Mrzljak, and Sljeme lithostratigraphic units is determined on the basis of conodonts and field relationships. The metamorphic age of the Triassic metasedimentary rocks from the Risnjak lithostratigraphic units is assumed to be Jurassic. Petrographic and geochemical analyses of ortho-greenschists point to a tholeiite basic magmatic protolith rock having T-MORB (transitional midocean-ridge basalt) characteristics. The ortho-greenschists of the Sljeme lithostratigraphic unit underwent retrograde metamorphism and show metamorphic zoning from the epidote–amphibolite facies to the lower parts of the greenschist facies. However, the greenschists of the Tusti Breg and Bliznec units are characterized by prograde metamorphism ranging from lower to higher greenschist facies. This metamorphism is associated with Jurassic subduction (165–150 Ma) and closure of the Western Tethys. Retrograde metamorphism took place during the collision of the Adriatic and Eurasian plates in the Lower Cretaceous (125–110 Ma).

The Miocene Climatic Optimum (MCO) represents a global warm period (approximately 17–14.7 Ma) interrupting a long-term period of Cenozoic cooling. To elucidate if bauxitization took place in southeastern European mid-latitude areas during the MCO, we studied a section of undated massive karst bauxite (Crveni Klanac, CK) in central Dalmatia, Croatia, hosted in Upper Cretaceous limestones and overlain by Miocene Sinj Basin lacustrine deposits. Integrated mineralogical, morphological and geochemical analyses indicate the predominant mineral phases of the homogenous bauxite matrix are authigenic, subhedral to euhedral kaolinite and gibbsite. The in-situ mineralization was a consequence of pedogenic processes, indicating the CK bauxites formed autochthonously. In situ U–Pb zircon ages of the lower, middle and upper parts of the CK bauxite are very similar, dominated by Miocene and Oligocene ages, indicating that they all share similar protolith(s). Subsequent high-precision chemical abrasion-isotope dilution-thermal ionization mass spectrometry (CA-ID-TIMS) analyses indicate a maximum depositional age (MDA) for the pre- bauxitic material of 16.9576 ± 0.021 Ma (2σ uncertainty, incorporating decay constant uncertainty). This MDA, a maximum age of autochthonous bauxitization, coincides with the onset of the MCO. Based on currently available geochronological constraints, the maximum timeframe for CK bauxitization was less than ~ 700 ka, which matches the records of the MCO in paleo- mid-latitude Europe. The potential imprint of pre- 17 Ma bauxitization and contribution of older (i.e., Upper Paleogene) bauxite deposits resedimented to the CK profile, as well as degree of potential parautochthonous origin of the CK bauxites, is yet to be investigated. More than simply aligning with regional and local reconstructions of continental climatic conditions during the onset and the early stages of the MCO, the high degree of autochthony of the CK bauxites provide a precise climatic constraint. For in-situ bauxitization to occur in the southeastern parts of mid-latitude continental Europe, paleoclimatic and paleoenvironmental conditions must have had mean annual temperature greater than 17–22 °C and mean annual precipitation of more than 1100–1200 mm.

Projekt SIMONA (eng. Sediment-quality Information, MONitoring and Assessment system to support transnational cooperation for joint Danube Basin water management) je Interreg projekt u okviru Programa međunarodne suradnje na području dunavskog slijeva. Dunavski slijev je sustav vodotoka koji se proteže kroz 19 europskih država, stoga je međunarodna suradnja jedino rješenje za kvalitetno i odgovorno upravljanje vodnim resursima tog slijeva. U projektu sudjeluje ukupno 29 institucija partnera iz 14 europskih zemalja. Dio njih čine znanstvene institucije, dok se dio odnosi na institucije zadužene za upravljanje vodama na državnoj razini. Svrha projekta je uspostava zajedničkog, međunarodnog sustava nadzora kakvoće drenažnog sedimenta, pri čemu se kakvoća odnosi na sadržaj prioritetnih anorganskih i organskih tvari propisanih Okvirnom direktivom o vodama Europske Unije. Cilj projekta je uskladiti i normirati protokole uzorkovanja, laboratorijskih analiza i procjene kakvoće drenažnog sedimenta, u svim državama koje sudjeluju u projektu. Također, cilj je izraditi mrežnu aplikaciju koja će služiti kao sustav za unos i procjenu podataka. Zajednički sustav nadzora omogućit će cjelovitu procjenu stanja kakvoće drenažnog sedimenta na području dunavskog slijeva, kao i razmjenu i usporedbu podataka među državama članicama projekta. Također, omogućit će pristup podacima i drugim zainteresiranim istraživačima.

Kaptaža K 2 izgrađena je u svrhu poboljšanja vodoopskrbe stanovništva otoka Brača. Tijekom izgradnje otkrivene su 4 pukotinske kaverne s vodom. Najveća od njih se nalazi u sjeverozapadnom dijelu gornje horizontalne etaže. Istražena je do dubine od 26 m. Na dnu postoji mogućnost daljnjeg napredovanja. Prolaz je dimenzija 1 x 0,5 m s dosta sedimenta na dnu. Donja etaža u vrijeme svih istraživanja bila je u cijelosti potopljena. U kaptaži K 2 ostvarena su izuzetna otkrića stigibiontne faune koja inače obitava u slatkovodnim podzemnim staništima na kopnu, ali i u izoliranim staništima na otoku Braču. Prvenstveno je posebno značajan nalaz nove svojte za znanost, rakušca Niphargus doli, koja je ovdje prvi puta zabilježena za neki otok, te goleme jadaranske vodenbabure Sphaeromides virei mediodalmatina, a jedino je poznato otočko nalazište dinarskog špiljskog cjevaša, Marifugia cavatica. Postignuta otkrića osnova su za posebnu pažnju i zasluženu stručnu zaštitu samoga staništa, a time i podzemne faune koja obitava u kaptaži K 2.