The mass extinction at the Triassic-Jurassic boundary (TJB) was one of the five major biotic crises of the Phanerozoic and coincideed with volcanic activity in the Central Atlantic Magmatic Province. The sections from the Budva Basin in Montenegro provide evidence of an abrupt termination of carbonate deposition across the TJB in a deep-water basin located close to a carbonate platform. For the first time, the stable carbon isotope record was measured in a deep-water TJB succession and, also for the first time, the measurements were done in both bulk carbonate and bulk organic matter. We demonstrated that the negative carbon-isotope anomaly and the drastic drop in carbonate (from 90% to less than 10%) occurred at the same time. These new data support the hypothesis that ocean acidification due to increased CO2, SO2 and CH4 fluxes not only promoted carbonate dissolution in the basin but must have also provoked a severe decline of skeletal carbonate-producing organisms on the adjacent platform. (7 citations in WoS)
COBISS.SI-ID: 31903277
In cooperation with Pennsylvania State University and Geological Survey of Norway, research was done on Precambrian, ca 2 billion years old sedimentary and volcanic rocks from north-western part of Russia. Analyses of stable C and O isotopes in both carbonate and organic matter revealed a negative δ13C anomaly with amplitude larger than 10‰. We have interpreted the release of large amounts of light carbon isotope into the ocean and atmosphere due to initial establishment of oxygen-rich atmosphere, in which massive oxydation of organic-rich rocks was enabled for the first time in the history of the Earth. Our data indicate that oxygenation of atmosphere did not occur 2.4 billion years ago as a single event, but rather as a series of events over hundreds of millions of years. (2 citations in WoS)
COBISS.SI-ID: 33386285
Age structure of the cave bear taphocenosis from Ajdovska jama has been studied. Individual age and season at the time of death was determined by analysis of dental tissues. The results indicate that mainly juveniles died in this cave and that the mortality was bound to the denning period. Therefore, Ajdovska jama was used primarily as a winter den. It was shown for the first time that also the small primitive kind of cave bear (Ursus ladinicus) could have lived considerably longer than 20 years. New data were given concerning root formation, dental cementum deposition and crown wear at different age.
COBISS.SI-ID: 33536045
Pliensbachian to Aalenian radiolarians from 220 samples collected at 30 localities around the world were studied. A database of 197 widely distributed species was used to construct a Unitary Association (UA) zonation for the interval. The resulting 39 UAs were merged into nine zones. These zones can be correlated worldwide and link previously established UA zonations for the Hettangian-Sinemurian and the Middle to Upper Jurassic. The paper is a reference publication on radiolarian biochronology of the Jurassic (6 citations in WoS, corresponding author Š. Goričan).
COBISS.SI-ID: 31903021
Mesozoic cherts and calcareous turbidites of the Pichakun Basin (Zagros Mountains) were studied. Radiolarians were used to define and date four lithostratigraphic units that span the interval from the Lower Jurassic to the middle Cretaceous. Based on sequence stratigraphy (stacking pattern), five second-order cycles were defined and interpreted primarily with respect to regional tectonics. The paper presents the first detailed sedimentological and biostratigraphic studies in Mesozoic basinal successions of southern Iran. (9 citations in WoS).
COBISS.SI-ID: 31533101