A study of sedimentary successions in different parts of the Eocene-Oligocene Promina basin has revealed major changes in the evolution of upper Promina Beds (PB). The first one refers to the origin ...of the erosional surface cutting different units ranging from Cretaceous limestones to different parts of older PB. It was formed during the fall of relative sea-level, and corresponds to a sequence boundary. This surface is overlain by onlapping alluvial sediments during the lowest relative sea level, and its early rise. The next main event is marked by a transgressive surface above the alluvium, that led to the deposition of shallow-marine limestones with diverse biota in the photic zone, as well as their lagoonal equivalents. This change resulted from an increase in accommodation space outpacing the rate of sediment supply. A further change refers to the deposition of mud with planktonic foraminifera on an outer shelf resulting from a further rise in the relative sea-level, which halted deposition of shallow-water limestones. The subsequent progradation of shelf and delta was related to the slowing down of the creation of accommodation space compared to the increase of sediment supply.
During Mesoscale Alpine Program (MAP) IOP-8, a strong stable layer formed over the Po Valley and northern Ligurian Sea. Based on observations, reanalysis data and prior studies, we hypothesize that ...differential advection (Lin et al., 2005) led to the formation of the stable layer and differential advection along with blocking of cool easterly flow by the western flank of the Alps over the Po Valley played significant roles in the maintenance of the stable layer. Numerical sensitivity tests with the MM5 model were performed to examine these possible formation and maintenance mechanisms of the IOP-8 stable layer. When the western flank of the Alps was removed, the stable layer still formed, but eroded more quickly and became much shallower and narrower at the later stage of IOP-8, which is consistent with the hypothesis. It was also found that the Dinaric Alps and evaporative cooling did not play significant roles in forming and maintaining the stable layer.
Mountain meteorological stations played an extremely important role in weather forecasting in the past because they were the only available data source on meteorological conditions several hundred ...metres above the sea level. Nowadays they are mainly used to estimate the climatic variations and the climate change trends in the environment that is not under the direct influence of the local anthropogenic factors. Two mountain meteorological observatories were chosen to illustrate climatic and bioclimatic trends and variability, Zavizan in Croatian Dinaric Alps and Kredarica in Slovenian Julian Alps. Both have the same monitoring protocol and similar instruments. Because of their unchanged surrounding since time of establishment the data from both observatories are extremely valuable for studying changes in sensitive mountain ecosystems in both countries. Data from the period 1955-2004 were used to assess mountain climatic and bioclimatic variability and trends in Croatia and Slovenia. Results point at the significant increase in the thermal bioclimate index (PET) based on the human energy balance models. At both sites the increase is mainly caused by temperature changes.
Mount Medvednica, situated at the SE edge of the Alps as an isolated mountain presents an attractive destination for large number of visitors during the whole year. Snow regime over Medvednica (about ...1000 m high), presents very risky factor in winter tourism. This study investigates snow cover frequency, duration and quantity for the referent period 1961-1990 at different profiles. At the top of Medvednica snow is falling on average on 54 days and at the altitude of 600 m on 30 days, most frequently 41-70 days, and 21-30 days respectively. Snow winter lasts from 121-239 days at the top to 104-186 days at 600 m a.s.l., but not with continuous snow cover. Days with snow cover >= 30 cm, necessary for alpine skiing and snowboarding, appears in 15% days annually at the top and in 7% of days at 600 m, that is a rather short duration for ski season. Snow cover >= 10 cm, necessary for development of cross-country skiing or snow mobiling has been analysed as well. Because of rather short duration of snow cover >= 30 cm, climatological analysis of relations between minimum temperatures and relative humidity have been done as a base for estimation of snow making possibilities at higher altitudes.
Bauxite Deposits of Lower Paleogene in the studied area are minor and rare. In these bauxites and bauxitic limestones oolitic textures and bochmite composition prevail a. in other Lower Paleogene ...bauxites of Dinadires, however, with a difference that these bauxites more frequently have increased contents of kaolinite. Bauxites were created during the emergence wich lasted from the end of Senonian to the Upper Paleocene - Lower Eocene. The analyzed bauxites have the increased contents of silica and they differ in regard to the contents of Al^sub 2^O^sub 3^ and microelements. There are differences also in the degree of sphericity of ooides, while the degree of roundness is more or less equal. On the basis of investigations so far, it may be concluded that the most advantageous conditions for the formation of Lower Paleogene bauxites have been in Istria and Herzegovina. Less favourable conditions have been in the area of today's islands of the Northern Adriatic. The most unfavourable were the areas of Southern Primorje and Northern Dalmatia, as shown in the example of Lower Paleogene deposits described here. PUBLICATION ABSTRACT
For approximately 120 years since the beginning of European geology up to the present day, Croatian geoscience has included intensive geological research of the Dinaride Ophiolite zone. Research ...results can be grouped into several periods depending on the basic predominant approaches of European and World geology. (1) During the flysch period, ophiolites were spatially connected with the flysch formations. (2) During the geosynclinal period ophiolites were classified into the “Diabas-Hornstein Formation”. (3) During the transitional period, characterized by the elaboration of the Basic Geological Map, a voluminous data were collected which could not be incorporated in geosynclinal ideas. (4) The last period is characterized by modern geodynamic interpretations resulting from global tectonics.
The upper part of the Promina Beds at their western extent is represented by two alluvial units: the Kunovac Beds and the Upper Alluvial Unit. The Kunovac Beds contain a high proportion of ...fine-grained sediments, and generally lacks debris flow deposits. The principal architectural components of the Kunovac Beds are (1) complex (multilateral, multi-storey) gravel-dominated sheets, which originated by the advance of mobile-channel belts, and were terminated by sudden abandonment, (2) smaller heterogeneous gravelly-sandy sheets, which originated in fluvial belts from a combination of sheet flows and channelized flows, (3) small isolated ribbons reflecting the filling of small channels, and (4) floodplain mudstones and sandstones. The basic style by which the Kunovac Beds, as well as the most part of the Promina alluvium were built up are the repeated advances and abandonments of the alluvial belts, and related stacking of coarse-grained sheets and floodplain deposits. The most important factors responsible for the dominance of this sheet-like geometry are high sediment supply and high aggradation and subsidence rates. Deposition of the Kunovac Beds occurred on alluvial plains, situated between the basin-margin proximal alluvium (including fans) and marginal-marine zone of the Promina Basin. The alluvial Promina Beds represent a transverse type of basin-fill pattern, whereas the deepest portion of the basin experienced longitudinal palaeotransport.
GEOLOSKA GRADA-TEMELJ RAZVOJA RUDARSTVA Crnkovic, Branko
Rudarsko-geološko-naftni zbornik,
12/1996, Volume:
8, Issue:
1
Journal Article, Conference Proceeding
Open access
The geology and significance of nonmetal minerals of Croatia are described. Croatia has a significant resources of some nonmetal minerals. Nonmetal deposts according the mobilistic view of the ...genesis and structure of Dinarides are described. PUBLICATION ABSTRACT
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