Lithologic Composition and Stratigraphy of Quaternary Sediments in the Area of the “Jakusevec” Waste Depository (Zagreb, Northern Croatia)

In the area covered by the “Jakusevec” waste depository, to a depth of 101 m, six lithological units were determined based on fieldwork and laboratory geologic-geophysical investigations. It was discovered that the silty-clayey units (units 1, 3 and 5) are covered by sandy-gravely (units 2 and 4) and gravely ones (unit 6), respectively. These units constitute the sediments of the Middle and Upper Pleistocene and Holocene and are separated by erosional unconformities. The Pleistocene gravels are predominantly of quartz-quartzite composition, while the Holocene ones are composed of carbonate cobbles and pebbles. In contrast, the sands exhibit a fairly uniform mineral composition throughout the column. The Pleistocene silt and clay are mostly composed of muscovite-illite and quartz with lesser amounts of chlorite, kaolinite and smectite. There is a difference in composition of this fraction in unit 6, where the quartz, calcite and dolomite particles prevail and smectite and illite/smectite are absent. Unit 3 is characterised by the goethite content. The Pleistocene layers were formed in a lacustrine-marshy environment while the Holocene sediments are fluviatile. This sedimentary sequence is interrupted by occasional terrestrial phases, or drying-up periods, dependent on the palaeoclimate conditions, particularly the interchange of cold and dry glacials with the warmer and more humid interglacial stage

Interdependence of Petrophysical Properties and Depth: Some Implications of Multivariate Solution on Distinction Between the Lower Pontian Hydrocarbon-bearing Sandstone Units in the Western Part of the Sava Depression

Statistical analysis of reservoir data from the Lower Pontian clastics (the most important hydrocarbon reservoir rocks in the Sava depression), supports established knowledge of the interdependence of petrophysical properties and depth. Irrespective of the focus that the reservoir data may be studied and presented, depth always emerges as a fundamental reservoir descriptor. This is particularly evident when studying the differences between widely spaced oil and gas fields, when the numerical model completely separates the two sets of descriptor variables, indicating two different sources of their internal variability. Porosity and permeability belong to “intrinsic rock properties” while depth must be ascribed to other sources, e.g. tectonic subsidence. Discriminant function weighted with depth (DF1) has such group centroid values, that zones can be drawn within a particular field that coincide with structural relationships. On the function marked with reservoir properties (DF2), group centroid values are higher close to the axes of palaeotransport channels, where sandstone layers are the thickest and particles are best sorted. Group centroid values on the third function (DF3) depict the areas of relatively higher permeability in the apical parts of structures, possibly caused by fracturing due to folding, or by cementation of other parts of reservoirs, where the circulation of pore waters was more pronounced. In the case of the most thoroughly investigated Zutica field, the inverse relationship between depth and porosity becomes evident when compared with the direction of palaeotransport and thickness of reservoir rocks on the respective structure and thickness maps

Tertiary Subsurface Facies, Source Rocks and Hydrocarbon Reservoirs in the SW Part of the Pannonian Basin (Northern Croatia and South-Western Hungary)

The Neogene sedimentary successions of the Drava, Sava and Slavonija–Srijem depressions in the SW part of the Pannonian Basin System are built up of three 2nd order megacycles separated by four major erosional unconformities. The first megacycle contains terrestrial to marine syn-rift and early post-rift sediments of Early to Mid-Miocene age. The second is built up of Late Miocene Lake Pannon deposits, while the third contains those sediments which were deposited in the remnants of Lake Pannon and in the subsequent fluvial systems, in areas of continuous subsidence associated with basin inversion from the Pliocene onwards. Most of the petroleum source rocks and reservoir rocks are of Miocene age and were formed during the first and second depositional megacycle. Conditions for the accumulation and preservation of large quantities of marine and terrigenous organic matter were most favourable during the Badenian, Sarmatian and Early Pannonian, in deep basin settings, partly associated with rifting. The generation of hydrocarbons was promoted by relatively high geothermal gradients during the initial and subsequent thermal subsidence. Various sedimentary environments produced deposits with good reservoir characteristics: e.g. fault-related talus breccia (mainly Lower Miocene), reefs (mainly Badenian), coastal, shallow marine (Karpatian, Badenian) and deltaic (Pannonian–Pontian) sand bodies or turbiditic sand lobes (mainly Pannonian). The hydrocarbon (HC) migration paths were often provided by the major unconformities bounding the three megacycles, as well as by faults, particularly around the basement highs

1,3-Dipolar Cycloaddition (Part II): Three-Component Cu(I) Catalysed Click Reactions

Cu(I) kataliziranim reakcijama sulfonil- odnosno fosforil-azida i terminalnih alkina nastaje intermedijar ketenimin koji reagira s nukleofilima kao što su voda, alkoholi, amini, piroli ili indoli, pri čemu nastaju odgovarajući amidi, imidati, amidini i supstituirani heterocikli, u jednom reakcijskom koraku. Te selektivne reakcije zbivaju se pri blagim reakcijskim uvjetima (sobna temperatura, prisustvo zraka i vode), bez steričkog i elektronskog utjecaja supstituenata na ishod reakcije.The Cu(I) catalysed reaction of sulfonyl or phosphoryl azide and terminal alkyne obtains a ketenimine intermediate that reacts with nucleophiles like water, alcohols, amines, imines, pyrroles or indoles producing corresponding amides, imidates, amidines and substituted heterocycles, in one reaction step. These selective reactions are characterised by mild reaction conditions (room temperature, presence of air and water), without steric or electron influence of substituents on the reaction outcome

Paleogeographic evolution of the Southern Pannonian Basin: 40Ar/39Ar age constraints on the Miocene continental series of notthern Croatia

The Pannonian Basin, originating during the Early Miocene, is a large extensional basin incorporated between Alpine, Carpathian and Dinaride fold-thrust belts. Back-arc extensional tectonics triggered deposition of up to 500-m-thick continental fluvio-lacustrine deposits distributed in numerous sub-basins of the Southern Pannonian Basin. Extensive andesitic and dacitic volcanism accompanied the syn-rift deposition and caused a number of pyroclastic intercalations. Here, we analyze two volcanic ash layers located at the base and top of the continental series. The lowermost ash from Mt. Kalnik yielded an 40Ar/39Ar age of 18.07 ± 0.07 Ma. This indicates that the marine-continental transition in the Slovenia-Zagorje Basin, coinciding with the onset of rifting tectonics in the Southern Pannonian Basin, occurs roughly at the Eggenburgian/ Ottnangian boundary of the regional Paratethys time scale. This age proves the synchronicity of initial rifting in the Southern Pannonian Basin with the beginning of sedimentation in the Dinaride Lake System. Beside geodynamic evolution, the two regions also share a biotic evolutionary history: both belong to the same ecoregion, which we designate here as the Illyrian Bioprovince. The youngest volcanic ash level is sampled at the Glina and Karlovac sub-depressions, and both sites yield the same 40Ar/39Ar age of 15.91 ± 0.06 and 16.03 ± 0.06 Ma, respectively. This indicates that lacustrine sedimentation in the Southern Pannonian Basin continued at least until the earliest Badenian. The present results provide not only important bench marks on duration of initial synrift in the Pannonian Basin System, but also deliver substantial backbone data for paleogeographic reconstructions in Central and Southeastern Europe around the Early–Middle Miocene transition