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Ivanščica Mt. is an inselberg in the transitional area where S-verging Southern Alpine structures overprint NNW-verging Dinaric structures (van Gelder et al. 2015, and references therein). It is composed of Triassic to Cretaceous shallow to deep-marine sedimentary succession of the Adriatic continental passive margin (Šimunić et al. 1976), overthrust by ophiolitic mélange (Babić et al. 2002). Early Cretaceous siliciclastic flysch-type deposits continuously overlaying pelagic limestones clearly indicates distal position of these successions on the continental margin. However, so far complete Jurassic succession on Mt. Ivanščica was never found, causing different interpretations of its Mesozoic history. Babić (1974) assumed the existence of Jurassic pelagic succession on top of the Late Triassic shallow-water carbonates, describing up to few meters of Early to Middle Jurassic condensed pelagic limestone overlain by Late Jurassic radiolarian cherts and pelagic limestones. Contrary, Šimunić et al. (1976) assumed shallow-marine conditions throughout the Early Jurassic followed by emersion until latest Jurassic. Our study revealed for the first time complete shallow-water to pelagic Jurassic succession on Mt. Ivanščica. Southern slopes of Ivanščica Mt. are mostly built of ophiolitic mélange, except for prominent hills built of the Late Triassic Dachstein limestone, which were so far interpreted as klippes (Šimunić et al. 1976), or olistoliths (Babić & Zupanič 1978). Our new data indicate continuous succession on top of Dachstein limestones composed of shallow-marine carbonates, represented by intraclastic-peloidal packstones to grainstones, gradually transitioning to wackestones with pelagic influence. The onset of pelagic sedimentation took place around the end of the Early Jurassic when thin bedded marls, shales, marly limestones with intercalated fine-grained calciturbidites were deposited. Higher in the succession Callovian to possibly early Tithonian radiolarian cherts are overlaid by calcarenites, late Tithonian to Early Cretaceous pelagic limestones and Early Cretaceous flysch-type deposits. Discovery of the Jurassic pelagic sediments allows for a new interpretation of structural relations on the Ivanščica Mt. In our opinion occurrence of Dachstein limestone, previously interpreted as klippes or olistoliths represent an imbricate fan. Because the Southern Alps thrust front in this area was interpreted according to these mapped klippes and nappe contact, our findings may also have an impact on the redefining of the easternmost Southern Alps thrust front. Babić, Lj. (1974). Jurassic−Cretaceous sequence of Mt. Ivanščica (North Croatia). Bull. Sci. Cons. Acad. Yugoslav. (A), 19/7−8, 180−181. Zagreb. Babić, Lj. & Zupanič, J. (1978). Mlađi mezozoik Ivanščice. In Babić, Lj. & Jelaska, V. (ured.): Fieldtrip Guidebook 3. Skupa sedimentologa Jugoslavije, 11–23. Hrvatsko Geološko Društvo, Zagreb. Babić, Lj., Hochuli P. A.. & Zupanič, J. (2002). The Jurassic ophiolitic mélange in the NE Dinarides: dating, internal structure and geotectonic implications. Eclogae Geologicae Helvetiae 95, 263–75. Šimunić, A., Pikija, M., Šimunič, Al., Šikić, K. & Milanović, M. (1976): Stratigrafsko - tektonski odnosi centralnog i istočnog dijela Ivanščice. 8. Jugosl.geol.kongres, Bled, 1974., 2, 3003-313, Ljubljana. van Gelder, I., Matenco, L., Willingshofer, E., Tomljenović, B., & Andriessen, P., Ducea, M., Beniest, A. & Gruić, A. (2015). The tectonic evolution of a critical segment of the Dinarides-Alps connection: Kinematic and geochronological inferences from the Medvednica Mountains, NE Croatia. Tectonics. 34. n/a-n/a. 10.1002/2015TC003937.

Maastrichtian to Palaeocene pelagic carbonates on the central Adriatic island of Svetac (Sveti Andrija) are the only outcrops reported to date that document pelagic deposition during the Cretaceous–Palaeogene (K–Pg) transition within the Adriatic Basin. An approximately 3 m thick succession at the Smokvica locality contains a rich and diverse planktonic foraminiferal assemblage which allows dating of the succession and the recognition of some biostratigraphic zones. The lower part of the Smokvica section consists of 1.5 m thick pelagic biomicrite characterized by the abundance of late Maastrichtian planktonic foraminifera that indicate the Abathomphalus mayaroensis Zone. An intercalation of intraclastic floatstone

The area of the Vinodol Valley and Bakar Bay represents a NW‒SE oriented valley in the NW Adriatic characterised by prominent historical and instrumentally recorded seismicity. As part of the greater geodynamic domain including the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone, new geological and structural data addressing the tectonic evolution of the area were collected in order to better understand the focal mechanisms of previous earthquakes and to enable identification of potential seismogenic sources. Mapped informal lithostratigraphic units mostly correspond to the Upper Cretaceous, Palaeogene and Quaternary successions described in other parts of the External Dinarides. However, a shorter stratigraphic range of the Gornji Humac fm., the youngest Cretaceous unit in the study area, was determined and suggests that the uplifted area in the central NW part of the Adriatic Carbonate Platform already comprised several thousand km2 (from W and NW Istria to Krk and Vinodol area) at the end of the Turonian. Structural measurements of the fault planes in the study area generally correspond to the existing structural model of the tectonic evolution of the Dinarides. However, in contrast to the SW vergences typical of the Dinarides, NE-vergent reverse structures are common, especially along the SW margin of the Vinodol Valley. Cross-cutting relationships suggest that transpressional (NW–SE and NE–SW striking dextral and sinistral faults) and extensional features (NW–SE and NE–SW striking normal faults) are structurally concurrent or younger than the reverse faults, suggesting a change in the palaeostress field during the Neogene–Quaternary, with prevalent transpression and radial extension. Comparison of results of the palaeostress field analysis and the constructed synthetic focal mechanisms on one side, with available focal mechanism solutions for earthquakes within the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone on the other, shows a favourable orientation of the observed NW‒SE and NE‒SW striking faults with respect to the recent compressional/transpressional stress field (N‒S oriented P-axis), indicating these as potential seismogenic sources within the study area.

The Cenomanian–Turonian boundary (CTB) on the intra-Tethyan Adriatic Carbonate Platform (AdCP) is generally characterised by a transition between microbially laminated and/or bioclastic limestones to calcisphere-rich massive limestone with bioturbated intervals, organic-rich interbeds, firmgrounds, as well as neptunian dikes, carbonate turbidites, tempestites and slumped structures. Compilation of the results from two study sites in the northwestern part of the AdCP and from previous research (on Istria Peninsula and islands in the Adriatic Sea in Croatia) provides a more complete overview of geological events and paleoenvironmental conditions that transformed the formerly contiguous shallow-marine environments during this time period. For the first time, a comparison between protected inner-platform area (Barban section) and a coeval intra-platform basin (Premuda Island section) during the CTB was made. This study utilized a combination of litho-, bio-, and microfacies studies with SEM, EDS, TOC, δ13C and δ18O stable isotope analyses. The stratigraphic successions start with shallow-marine carbonate deposits of the Milna Formation that is conformably overlain by the drowned-platform deposits of the Sveti Duh Formation on the platform and by the Veli Rat Formation in the contemporaneously developed intraplatform basin. These deposits are in turn overlain by the Gornji Humac Formation, which represents re-establishment of shallow-marine depositional systems on the AdCP, whereas the deeper water environment persisted in the intra-platform basin until the Santonian. Despite diagenetic modifications of shallow-marine carbonate deposits, the results of TOC and stable isotope analyses indicate the influence of global Oceanic Anoxic Event 2 (OAE2). Combination of local and regional synsedimentary tectonics and global Late Cretaceous sea-level changes accompanied by anoxic and hypoxic conditions, extinction of numerous benthic foraminifera, diversification and expansion of planktonic foraminifera and calcareous dinoflagellates, provide new insights into the character of the CTB interval in this part of the Tethyan realm.

Active tectonics in long-lived orogenic belts usually manifests on the preexisting inherited structures. In the Kvarner region of the External Dinarides, an area with low-to-moderate seismicity related to the Adriatic microplate (Adria) northward movement, we deal with faults in predominantly carbonate rocks within tectonically complex NW-SE striking fold-and-thrust belt, which makes the identification and parametrization of the active structures challenging. Moreover, anthropogenic modifications greatly complicate access to the surface geological and geomorphological data. This paper demonstrates results of focused multidisciplinary research, from surface geological mapping and offshore shallow seismic surveys to earthquake focal mechanisms, as an active fault identification and parametrization kit, with a final goal to produce an across-methodological integrated model of the identified features in the future. Reverse, normal, and strike-slip orogen-parallel (longitudinal) to transverse faults were identified during geological mapping, but there is no clear evidence of their mutual relations and possible recent activity. The focal mechanisms calculated from the instrumental record include weak-to-moderate earthquakes and show solutions for all faulting types in the upper crust, compatible with the NE-SW oriented principal stress direction, with the stronger events favoring reverse and strike-slip faulting. The 3D spatial and temporal distribution of recent earthquake hypocenters indicate their clustering along predominantly subvertical transversal and steeply NE-dipping longitudinal planes. High-resolution shallow seismic geoacoustical survey (subbottom profiler) of the Quaternary sediments in the Rijeka Bay revealed local tectonic deformations of the stratified Late Pleistocene deposits that, along with overlaying mass-transport deposits, could imply prehistorical strong earthquake effects. Neotectonic faults onshore are tentatively recognized as highly fractured zones characterized by enhanced weathering, but there is no evidence for its recent activity. Thus, it seems that the active faults are blind and situated below the thin-skinned and highly deformed early-orogenic tectonic cover of the Adria. A strain accumulating deeper in the crust is probably irregularly redistributed near the surface along the preexisting fault network formed during the earlier phases of the Dinaric orogenesis. The results indicate a need for further multidisciplinary research that will contribute to a better seismic hazard assessment in the densely populated region that is also covered by strategic infrastructure.

We disagree with many of the concerns raised by Font et al., (2017) and take this opportunity to clarify matters. We wish to emphasise that in our paper (Korbar et al., 2017), as well as in the first report on the “potential” Cretaceous–Palaeogene (K–Pg) tsunami in the Adriatic region (Korbar et al., 2015), we reported on rare shallow marine distal K–Pg records that differ from the dominantly deep marine records commonly reported in other papers. We did not include more references on the latter, since that was not a goal of our paper, and we encourage the authors of the Comment themselves to make additional research of the Likva section, especially the issues that are criticised. This article is protected by copyright. All rights reserved.

The island of Cres is located in the northern part of the Adriatic Sea. The island is built up of predominantly Cretaceous carbonates deposited in north-western part of extensive and long-lasting Adriatic Carbonate Platform. Owing to the influence of synsedimentary tectonics supported by eustatic changes during the latest Albian/Early Cenomanian, different sedimentary environments were established: from shallow intraplatform basin and related slope, across basin margin to protected shallow-platform. During the Early to Middle Cenomanian rudist communities (ichthyosarcolitid/caprinid/radiolitid) flourished along a relatively high-energy intraplatform basin margin. Fair amounts of coarse-grained bioclasts, derived almost exclusively from broken rudist shells, were deposited over a marginal depocenter. Contemporaneously, pithonellid wackestone-packstones containing microbioclasts and planktonic foraminifera were deposited basinward while marginal bioclastic sediments and limestone blocks of the basin margin origin were sporadically deposited within the basin. The opening of the Cres intraplatform basin was aborted and the basin was finally filled up during the Late Cenomanian. Since the Cres intraplatform basin was established at the beginning of the Cenomanian it probably represented the initiation phase in the north-western extension of the later Adriatic Trough development.

The mid Cretaceous shallow-water limestones on the islands of Cres and Losinj contain abundant and diversified orbitolinid foraminifera. A biostratigraphy, based on the orbitolinid taxa and their chronostratigraphic interpretation, is proposed for the Aptian, Albian and Cenomanian deposits in the area investigated. Four orbitolinid biozones have been recognized: (1) Palorbitolina lenticularis Taxon-Range Zone in the Lower Aptian; (2) Orbitolina ( Mesorbitolina ) texana Assemblage Zone in the Lower Albian, the body of strata being characterized by a distinctive assemblage of Orbitolina ( Mesorbitolina ) texana , O. ( M .) subconcava , O . ( M .) parva and O. ( M .) pervia ; (3) ‘Valdanchella’ dercourti Taxon-Range Zone in the basal Upper Albian; and (4) Orbitolina ( Conicorbitolina ) conica Abundance Zone in the Lower–Middle Cenomanian, a body of strata in which the abundance of the species Orbitolina ( Conicorbitolina ) conica is significantly greater than is usual in the adjacent parts of the section, regardless of either association or range. The established biozones on the islands of Cres and Losinj are correlated with orbitolinid biozonations and orbitolinid stratigraphic distributions in the adjacent areas, with emphasis on the Karst Dinarides.