Geochemical discrimination of Early Palaeogene bauxites in Croatia

Geochemistry of Lower Palaeogene bauxites – unique signature of the tectonostratigraphic evolution of a part of the Croatian Karst

“…erosion caused by uplift (MINDSZENTY et al, 1995), and also a prolonged period of terrestrial conditions necessary for the accumulation and diagenesis of the protobauxitic material. Presumably, the geochemical signal of the ILPB has responded to the coeval tectonostratigraphic constraints in a somewhat different way with respect to other LPB groups marked by different stratigraphic positions within the ADCP (Dinaric domain, sensu KORBAR, 2009;KOVAČEVIĆ GALOVIĆ et al, 2012). This premise infers a tacit antagonism between the ILPB and the other LPB groups, concerning their geotectonic setting -Adriatic vs. Dinaric domains of the ADCP -whereby the latter are associated with an unconformity formed during the supposedly shorter Late Cretaceous (Santonian-Early Campanian) to Palaeogene (Early-Middle Eocene) hiatus and, as a result, are underlain by carbonate bedrock of approximately the same age.…”

“…The most recent investigations of bauxites in Croatia had addressed the root causes of geochemical variations observed in the bauxite deposits of Lower Palaeogene age (LPB) from the Croatian karst (KOVAČEVIĆ GALOVIĆ et al, 2012) (Fig. 1), focusing especially on the Istrian Peninsula due to its specific geodynamic evolution through Cretaceous to Palaeogene times (PEH & KOVAČEVIĆ GALOVIĆ, 2014).…”

Discrimination of topsoil environments in a karst landscape: an outcome of a geochemical mapping campaign

“…In addition, data processed in this way can develop a mapping quality that explains the relationship among the original variables more clearly. The aims and principles of DFA are described in detail elsewhere (e.g., [18,20,61]) and have been explained repeatedly by the present authors in various geochemical and environmental studies [23,26,28,34,49,50,52,53,65]. It suffices to say in this paper that DFA is a multivariate method that is particularly effective in pursuing the major sources of between-group differences which, in this study, derive their origin from the accumulation of heavy metals and possibly harmful elements (PHE) in karst soils.…”

“…To this purpose, the topsoils collected during the multi-year geochemical mapping campaign (GAC) are examined in light of the various geological and environmental criteria [40-42, 51, 58, 59]. These criteria, as in other geochemical studies on similar problems in the area [34,52,53], are exploited in this study as the most revealing avenues through which the processes mentioned above can be most effectively understood. The criteria are autonomous with regard to the soil geochemistry such as the geological (lithological) setting, description of land use, soil types, or geographical position (with climate implications), which provide the most efficient means of a priori arrangement of the soil samples into a number of coherent and exhaustive statistical groups.…”

Geological and structural map of the southeastern Pag Island, Croatia: field constraints on the Cretaceous - Eocene evolution of the Dinarides foreland

“…Relative sea level changes occurred due to the interplay between global eustatic variations and synsedimentary tectonics during the polyphasic convergence between Eurasia and Adria plates, which began in Late Jurassic times (Aubouin et al, 1970;Schmid et al, 2008) and is still active (Kastelic and Carafa, 2012;Kastelic et al, 2013). With the propagation of the orogenic front to the SW, the AdCP underwent dissection and emersion during a major event recorded by a regional unconformity surface, locally bearing bauxite (Vlahović et al, 2005;Kovačević Galović et al, 2012;Peh and Kovačević Galović, 2016). Sedimentation resumed in Early Eocene times, when the Northern Dalmatia constituted the foreland basin of the Dinarides.…”