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Scarce basin remnants of Cretaceous synorogenic sediments exposed in the Medvednica, Ivans ˇc ˇica, Z ˇumberak Mts. and Samobor Hills of northern Croatia record the early orogenic history of the NW Dinarides. The provenance of sandstones from five clastic formations (Os ˇtrc, Bistra, Kravljak, Vivodina and Glog) which cover a time span from Early to late Late Cretaceous was studied by combining petrography, whole-rock geochemistry, heavy mineral chemistry and detrital zircon fission track dating. These sediments record at least two major regional thermotectonic events which correlate well with those affecting both the Alps and the Tisza-Dacia unit to the north and east, and the central Dinaride region to the south. Short zircon fission track lag times in Barremian to Albian sediments indicate that continental fragments of the distal Adria plate margin underwent relatively fast, synsedimentary exhumation in the Early Cretaceous. Moreover, a clear dominance of Campanian zircon cooling ages (80-73 Ma) in Maastrichtian sandstones indicates detritus deriving from the erosion of newly and rapidly exhumed basement units which had undergone Late Cretaceous metamorphism in the Eastern Alps and/or the Tisza-Dacia region. Probably, the rapid Maastrichtian erosion generating metamorphic detritus occurred to a great extent on neighbouring Austroalpine basement units, and/or on the upper plate Tisza-Dacia unit during the subduction stage or the initial stages of the continent-continent collision with Adria. Development of the accretionary wedge probably resulted in a renewed availability of ophiolites for erosion within small and/or dynamically changing catchments, which can be deduced from the notable differences in reconstructed source lithologies for the coeval Glog and Vivodina formations. Combined evidence from sedimentary provenance indicators precludes the Dinaride (Adriatic) basement as a significant source for the Maastrichtian sediments.

Cr-spinel is a common heavy mineral in the sandstones of Cretaceous synorogenic sedimentary formations of the NW Dinarides, Croatia. The rocks occur in isolated exposures in the uplifted basement units of Medvednica, Ivanščica, Ž umberak and Samobor Mountains near Zagreb. In this area, evidence of the early Alpine evolution of the Dinarides is obscured due to strong dismemberment of pre-Tertiary tectonostratigraphic units resulting from an intense tectonic history, as well as due to the widespread sedimentary cover of the Pannonian Basin. Electron microprobe analyses of detrital Cr-spinels from the Oštrc Formation reveal that in the Early Cretaceous the ophiolitic source area was predominantly composed of harzburgite peridotites and associated cumulate rocks, which developed in a supra-subduction zone setting. The supply of Cr-spinels with the same chemical signature remained dominant until the end of the Cretaceous, suggesting that exposed remnants of the same ophiolite belt persisted through the Cretaceous and/or that recycling was significant. Similarities with data reported from the Northern Calcareous Alps and the Transdanubian Central Range imply that a rather extensive harzburgitic ophiolite belt probably extended along the Adriatic margin during the Early Cretaceous. A slight trend of increasing variation in the Cr# is observed from the Early to the latest Cretaceous, suggesting that the source areas became more heterogeneous with the ongoing Cretaceous tectonic evolution. Differences in Cr-spinel compositions in two contemporaneous latest Cretaceous formations are well in line with existing data on heavy mineral proportions, which together identify contrasting hinterland geology for these formations and strongly suggest the coeval existence of two separate basins.

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Terrestrial laser scanning (TLS) in combination with Unmanned Aircraft System (UAS) and modern computer based photogrammetry is currently the best approach for the acquisition of high-resolution 3D spatial information. Highly realistic 3D spatial data sets are becoming the basis for detailed geological studies, providing a multidisciplinary approach in the study and research of both underground and above ground sites. To emphasize the variety of possible implementations of these state-of-the-art methodologies, four characteristic and yet quite different case studies are presented where such geodetic techniques are successfully employed. The presented case studies demonstrate that TLS and UAS photogrammetry, as non-contact surveying methods, are able to reduce survey time and total project costs. As added value, they provide high-resolution data that can be analyzed in a virtual environment from a sedimentological or structural aspect. Stored digital documentation also allows future multi-temporal spatial data comparison at any timeframe and scale, thus enhancing any target geological data gathering and analyses at the studied sites.