The up to 450 m-thick Upper Jurassic Lemeš Formation includes organic-rich deep-water (max. ~ 300 m) sedimentary rocks deposited in the Lemeš Basin within the Adriatic Carbonate Platform (AdCP). The ...Lemeš Formation was investigated regarding (1) bio- and chemostratigraphy, (2) depositional environment, and (3) source rock potential. A multi-proxy approach—microfacies, Rock–Eval pyrolysis, maceral analysis, biomarkers, and stable isotope ratios—was used. Based on the results, the Lemeš Formation is subdivided from base to top into Lemeš Units 1–3. Deposition of deep-water sediments was related to a late Oxfordian deepening event causing open-marine conditions and accumulation of radiolarian-rich wackestones (Unit 1). Unit 2, which is about 50 m thick and Lower early Kimmeridgian (
E. bimammatum
to
S. platynota,
ammonite zones) in age, was deposited in a restricted, strongly oxygen-depleted basin. It consists of radiolarian pack- and grainstones with high amounts of kerogen type II-S organic matter (avg. TOC 3.57 wt.%). Although the biomass is predominantly marine algal and bacterial in origin, minor terrestrial organic matter that was transported from nearby land areas is also present. The overlying Unit 3 records a shallowing of the basin and a return to oxygenated conditions. The evolution of the Lemeš Basin is explained by buckling of the AdCP due to ophiolite obduction and compressional tectonics in the Inner Dinarides. Lemeš Unit 2 contains prolific oil-prone source rocks. Though thermally immature at the study location, these rocks could generate about 1.3 t of hydrocarbon per m
2
surface area when mature.
Reinterpretation of some earlier published data on pelagic beds in Lika, Dalmatia, western Bosnia, eastern Hercegovina and Monte-negro confirms the existence of a pelagic, labile Interplatform Belt ...(Epiadriaticum) in the frame of the Outer Dinarides.
The bauxite deposits occur along the Lower Kimmeridgian-Upper Kimmeridgian contact in the Nanos area. The main bauxite minerals are boehmite and gibbsite. The Nanos deposits are an example of ...bauxites deriving from limestone residuum, aeolian material and alluvium. Some Jurassic marly, calcareous rocks proved relatively high in alumina, iron and silica, and are probably a significant source of bauxite material. The Nanos bauxites are compared with late Jurassic bauxites from the western Istria.
The Eocene clastics of the NW part of the island of Pag overlie carbonate platform deposits and are dominantly sandy. Besides minor components, they include cross-laminated and cross-bedded ...sandstones produced by marine tractive flows, mostly directed toward E, and ESE, and dominantly massive sandstones probably deposited by gravity flows. The area was situated close to sand-rich sources and river mouth(s). Possible settings include a delta-related shallow-marine area, and a sea strait. Structural deformation intervened very early in the history of a complex outer dinaric foreland realm and governed its subsequent evolution, in contrast to a simple foreland trough envisaged before.
The paper provides a description of the poorly known Upper Nummulitic Limestones exposed in the North Dalmatian foreland basin of the Outer Dinarides in Croatia. This formation originated on a ...land-attached ramp-type platform with a temperate sediment production. It transgressively overlies older platform limestones and includes limestones deposited in very shallow, restricted settings, which subsequently evolved into carbonate platform environments typified by diversified biota. The succession terminated at a drowning unconformity, which is intra-Bartonian (Middle Eocene) in age based on biostratigraphic interpretations of the larger foraminifera present. This study demonstrates that the history of the carbonate platform of the Outer Dinarides extends into the Bartonian and that the studied limestones document the youngest, hitherto unknown stage in the platform development. The SW margin of the Upper Nummulitic platform was dissected by faults and prone to collapse, which represented the source for megabreccias deposited in an adjacent basin. This platform-basin system represents a new element in the sedimentary and tectonic evolution of the Dinaric foreland.
Ovaj prilog dobavlja opis slabo poznatih Gornjih Numulitnih Vapnenaca iz sjeverno-dalmatinskog predgornog bazena Vanjskih Dinarida Hrvatske. Ta formacija nastala je na platformi tipa rampe, koja je ...pripadala umjerenoj sedimentacijskoj provinciji. Ona transgresivno naliježe na starije platformske vapnence i početno uključuje vapnence taložene u vrlo plitkim, ograničenim uvjetima, a zatim vapnence s diverzificiranom biotom. Slijed se svršava tonjenjem (tzv. drowning unconformity), koje se dogodilo unutar Bartonija na što upućuje biostratigrafija nađenih velikih foraminifera. Ova studija pokazuje da se povijest karbonatne platforme Vanjskih Dinarida proteže i u Bartonij, te da proučeni vapnenci dokumentiraju najmlađi, dosad nepoznati stadij u razvitku platforme. Jugozapadni rub Gornjo-numulitne platform bio je zasječen rasjedima i sklon kolabiranju te je pretstavljao izvor za megabreče taložene u susjednom bazenu. Taj sustav platforma-bazen pretstavlja novi element za razmatranje taložnog i tektonskog razvitka Dinarskoga predgorja.
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