Areas around seaports are prone to environmental damage. In the port of Koper, Slovenia hematite was being transhipped during a strong wind in March 2011. The broader area was accidentally covered with hematite dust. Some members of the public and media claimed the dust was toxic and was harmful to the population. Since the soils had already been geochemically mapped, we repeated the sampling to compare the geochemical composition of the topsoil. No soil contamination was established. The enrichment factors show depletion of majority of elements. According to the distances from the dust source, SiO2, Na2O and Cr have decreasing, and Fe2O3 increasing trends. The SiO2 and Cr content correspond to the concentration of sand, and the dissolution of carbonate closer to the sea. Co and Ni are probably bound to the clay minerals. Cu, Pb, and Zn could have some anthropogenic contribution.
COBISS.SI-ID: 38586669
In Snežna Jama cave, Slovenia, extensive speleothems composed of dolomite, aragonite and hydromagnesite have been found, occurring as 5 cm thick globular crusts coating the host rock. Dissolution of the dolostone host rock has provided Mg, which is the main control on the precipitation of aragonite, dolomite and hydromagnesite. Dolomite precipitation could be promoted by increased Mg/Ca ratios due to the prior precipitation of calcite and aragonite and by forced degassing due to ventilation caused by the existence of shafts cutting the main cave passage and a former entrance to the cave. However, in many caves such conditions do not lead to the formation of dolomite and so we discuss other mechanisms which might promote dolomite precipitation, like the possible contribution of microbes, or the transformation of precursor phases such as amorphous Ca-Mg carbonates, or hydromagnesite.
COBISS.SI-ID: 38627629
The genetic relationship between clays and precipitation of carbonates has lately received an increased interest (e.g., in the exploration of giant oilfields in the southern Atlantic), since a clear correlation between Mg-Si films/needles/gels and carbonate minerals, particularly dolomite, has been recognized. The genetic and diagenetic relationships between Mg-clays and Mg-carbonates of Castañar Cave show that the the presence of colloidal Si-Mg phases in the system, biotic or abiotic in origin, may play an important role in the precipitation of dolomite.
COBISS.SI-ID: 38610733
The Palaeolithic of southern Central Europe has a long history of archaeological research. Particularly the presence of numerous osseous projectile points in many early Upper Palaeolithic (EUP) assemblages in this region has attracted the attention of the international research community. The scarcity of properly identified and well-dated Aurignacian contexts represents an obstacle for investigation of the nature and timing of the Middle to Upper Palaeolithic transition. In this context, the question of whether Neandertals made Aurignacian osseous projectile points, either on their own or as a consequence of cultural interaction with anatomically modern humans, still remains an open issue. Here we reassess the EUP record of Slovenia by evaluating the Aurignacian character of the assemblages from Potočka zijalka, Mokriška jama and Divje babe I in the light of their suggested roots in the local Mousterian. We provide a comprehensive description of the lithic industry from Potočka zijalka, which represents one of the rare EUP assemblages of southern Central Europe with a representative number of lithic artefacts to be analysed from the perspective of lithic technology and raw material economy. Our re-analysis of the Slovenian assemblages is backed by a series of 11 new ultrafiltered collagen 14C dates obtained directly on associated osseous projectile points from the studied assemblages. The Aurignacian of Potočka zijalka underlines the remarkable consistency of the Early Aurignacian with low typotechnological variability across Europe, resulting from a marked dependence on transported toolkits and raw material conservation. The new radiocarbon determinations for the Aurignacian of Slovenia appear to post-date the 34−32 ka BP threshold for the last Neandertals in the region. Although not falsified, the hypothesis of Aurignacian bone tools in southern Central Europe as a product of late Neandertals is not supported by our re-examination of the EUP record of Slovenia.
COBISS.SI-ID: 37760045
The Guevgueli Ophiolite Complex near Demir Kapija (Eastern Vardar Ophiolitic Unit) was studied for the age and facies of the overlying sediments. Cherts in direct contact with basalts are dated to late Bathonian–early Callovian with radiolarians. The post-obduction sequence, here informally named the Demir Kapija group, is composed of polymictic conglomerate, probably Kimmeridgian in age, and a more than 350 m thick carbonate succession. The carbonate succession consists of hemipelagic, slope and platform-margin facies, and contains algae and benthic foraminifers indicative of the Tithonian age. The Demir Kapija group is an exceptionally well preserved example of platform evolution on top of obducted ophiolites and may serve for better understanding of other genetically similar carbonate platforms that characterized the closing Meliata-Maliac-Vardar branch of the Neotethys.
COBISS.SI-ID: 37759021