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Prvi dio inovacije obuhvaća izračun geološke vjerojatnosti, uvođenjem nekoliko izvornih postavki koje pojednostavljuju (objektiviziraju) kalkulaciju uz zadržavanje pouzdanosti. Proračun obuhvaća standardne geološke kategorije za takvu metodologiju, no uz pet jednoobraznih vjerojatnosnih razreda čiji su nazivi povezani s vjerojatnošću otkrića ležišta (dokazani događaj unutar geološke kategorije uz razrađene rezerve na tom lokalitetu ili blizini – 1, 0 ; dokazani događaj uz nerazrađene rezerve – 0, 75 ; vjerojatan događaj i rezerve – 0, 50 ; mogući događaj i rezerve – 0, 25 ; nedokazani i eventualno spekulativan događaj – 0, 05). Drugi dio inovacije prikazuje upotrebu funkcije korisnosti za određivanje prihvatljivog novčanog iznosa ulaganja u istraživanje potencijalnog otkrića. Taj iznos ovisi o veličini tvrtke, odnosno proračunu za istraživanje u odabranoj naftnogeološkoj provinciji za pretpostavljeni volumen ugljikovodika. Ukupna vjerojatnost sastavljena je od geološke vjerojatnosti postojanja naftnogeološkog sustava, te rizika financijskog ulaganja u očekivanu dobit. Metoda je isprobana na nekoliko projekata i naftnogeoloških područja, a poglavito u prostoru Bjelovarske subdepresije.

The Adriatic belt of the AdCP, or what is to-day the Adriatic zone of the External Dinarides, is largely built up of Upper Cretaceous platform limestones. They have variable thicknesses in different structural settings, and, in adition to that, a rather pronounced facies variability. By means of paleostress data analysis it was possible to distinguish three kinematic events, documented by their sedimentary signatures, including slumps, paleofissures, dessication cracks, polymictic fissure breccias (=neptunian dykes), etc. Also, the analysis of the paleostress data showed that the majority of present structures were imprinted upon the older (= Ladinian) structures ; those, in turn, were being subject to repeated movements and thus represented the origin of the later (= recent) structural units. During the Late Cretaceous, both types of kinematic deformations, i.e., the radial and the tangential ones, have been active in the Adriatic belt of the External Dinarides. The oldest, Cenomanian, movements were characterized by radial tectonics (= the D1 deformational event). The Cenomanian-Turonian transition was a more quiet phase, characterized by the deposition of a new type of limestone - pelagic micrite (probably as a result of global eustatic sea-level highstand, which temporarily drowned the AdCP) that leveled the pre-existing paleomorphology. The end of the Santonian represents a turning point in kinematic activity, i.e., the tangential tectonics predominates (= the D2 deformational event). It produced important plicate deformations within individual segments of the AdCP (the NW-SE striking folds of 10 m- to 100 m-sized amplitudes and kilometer-sized limbs). While in thus formed synclines the deposition of pelagic micrites again took place, in the elevated parts of the anticlines the sedimentation was locally interrupted or, alternatively, shallow-water deposition continued. By the end of the Campanian, and due to the tangential stress, bioclastic sediments filled up and leveled the depressions. At the same time, the sedimentation in the largest part of what is to-day the onshore zone of the External Dinarides came to an end.

Data on dynamics of the recent structural fabric were collected as part of the search for structures favorable for further petroleum-geological exploration.

Principles of petroleum exploration for geologists. Practical work on the geophysical data from PBS in Croatia aimed at evaluation of the remaining potential in the Neogene clastic basin fill. Joint analysis of exploration efficiency.

Identifications of the petroleum systems were performed for the southern, marginal part of the Pannonian basin and the Croatian part of the Adriatic offshore. Geological, hydrodynamic, thermal complexity and hydrocarbon differences of these areas enable their division into several main petroleum systems.

Deposits of Markada and Kurrachine Dolomite Formations were studied in more detailsin the area of INA's Concession, Hayan Block in central Palmyrides, Syria. Database comprises logs, cores, cuttings and reports from the surrounding wells. Palmyrides are considered as atype example of an intracontinental transpressive mountain belt, 400 km long and 100 km wide, striking N45&ordm ; ; E from the Anti-Lebanon Mountains and the Dead Sea fault system. Markada formation, Carboniferous, predominantly consist of shale/sandstone intercalations with minor siltstone and limestone. Sandstones were grouped into four (A, B, C and D) genetic packages for correlation purposes. The depositional environment was a near shore marine setting. The major sanstone layers were deposited as small delta distributora mouth bars and/or meandering tidal channel sands that merged and pinched out laterally. Minor sandstone and siltstone were deposited as over bank depositsand crevasse-splay deposits from the main distributora channels. Intertidal clays and occasional limestone, are evidence of period of low clastic sedimentation rates (low energy) and flooding of the shallow marine platform that allowed the deposition of thin carbonate beds. Petrographic analyses indicate that sandstones southern of the study area is classified as sub arkoses, moderately sorted with angular to subangular quartz grains and K-feldspars (microcline) and plagioclase feldspars as subordinate components. Subarcose sandstones are of granite provenance, usually deposited proximal to the source area. On the other side, sandstones from the northeast are quartz arenites, containing sub rounded to sub angular grains of monocrystalline quartz and rare chert. Dandstones are fine grained and well sorted. Quartz arenite sanstones seem to more distal that subarcose sandstones from the south. Porosity=12-14%, permeability h=26-75 md, v015-46 md. It may be concluded thata the source area for clastics was from southern provinces (Arabian shield) from where was via deltaic/river system transported to the shallow shelfs and epeiric seas on Gondwana land which was to the NE during Carboniferous surrounded by the Palaeo-Tethys ocean. According to the wire line logs motives interpretation and "depositional energy modelling" it is evident that higher energy is always connected with better reservoir properties. Kurrachine Dolomite Formation, Middle-Upper Triassic, consists predominantly of various carbonate types, dolomite and limestone, evaporites, shale/claystoneand represents the major Mesozoic reservoir for gas (predominantly), condensate and oil in Palmyrides. Formation is subdivided according to its reservoir properties into subunits C2, D1, D2 (from the top to the bottom). c2-Secondary reservoir-interbedded dolomite, limestone, anhydrite, shale and claystone. The more evaporitic carbonate phases and anhydrite in the C2 are interpreted as chemical sediments of lacustrine (saline-lake) origin. These cycles were driven by cyclical variations in rainfall, aridity, influx of clay-silt fines into the basin, repeated isolation of the basin and repeated phases of evaporation of gypsum precipitation. Each of the sedimentary cycles is capped by decimetre to metre scale unit of bedde anhydrite. The plaeogeographic model for C" is a basin which many times "went lacustrine" trough repeated interludes of evaporation to gypsum precipitation, and isolation from Tethys, Average porosity 5-8. D1-Primary reservoir-it is generally shoaling-upward, cyclical carbonate sequence devoid of terrigenous sediments. Terminates upward at an irregular, sharp contac where it is overlain by a sequnce of mostly dark gray to dark greenish-gray shale. Long cycle of the D1 was accumulated an a dominantly muddy, middle/lower to inner/shallow shelf that shoaled briefly to tidal-flat conditions. D1 is divided into 3 informal subzones: Lower Dolomite: has the best reservoir properties ; represents lower partof the long marine cycle. Consists of poorly stratified, fine-to-coarse crastalline dolomite. Original grains and textures are obscured to some extend because of fabric "coarsening" by dolomitisation, but Lower Dolomite appears to have been bioclastic carbonate sand. Pore system are varied and include intercrystal, occasional, moldic and interparticle pores and a abundance of rather small, mm-cm scale vugs of irregular shapes. Middle Limestone: upper part of the long marine cycle. Represent a regime of lime-mud accumulation on a shallow shelf that ended with brief shoaling to intertidal conditions. Upper carbonate: includes Upper Dolomite interval and minor evaporites at the top. Shoaling upwared evaporite-capped cycle. Average porosity 8-9%. D2-reservoir-sequence of interbedded shale, dolomite and lime mudstone. Upper part of D2 represents a shoaling-upward succession from basinal or distal ramp/slope to lower shelf/ramp sediments. The upper D2 contains no evaporites and unlike the overlying D1 and C2shows no evidence of deposition in either shallow-marine, peritidal or non-marine environments. Average porosity 2-7%.

The exploration area in the Croatian part of the Pannonian basin covers 30,000m2. Approximately 950 exploration wells werw drilled there, 30,650 km of seismic sections were shot, and some 2,200 km2 of 3D seismic. Until 1999, the complete Croatian production of hydrocarbons came from this area-from 49 oil and gas fields a cumulative of 160 million m3 of OE werw produced (till 31st Dec. 2001). HC production is in decline in the last decade, with stagnation in reserve replacement. The remaining reserves are presently reduced to a little over 7 million m3 of oil, and 31 billion m3 of gas. Apart from application of new techologies, the best solution for continuation and stabilization of exploration and production is seen in emplacement of EOR methods, especially in CO2 flooding of oil reservoirs. The sediments of the Neogene system are divided into three depositional megacycles of the 3rd order, composed of sequences of well- defined lothological units that are of the status of formations. The first, oldest megacycle with various and heterogeneous lithological composition is of Early Miocene and Middle Miocene age. Fine-grained clastic source rocks are contained therein together with a number of the largest HC pools, like Beničanci and Molve. The second depositional megacycle (Late Miocene) is characterized by a monotonous sandstone-marl sequence with all transitional lithologies. Numerous sandstone reservoirs are found in this unit - the largest are at the Stružec, Žutica, Ivanić-Grad and Kloštar Ivanić fields. The third megacycle is of Pliocene-Quaternary age, and is composed of sand, clay, and gravel with some lignite/peat sporadically. This unit is of subordinate petroleum-geological importance at present. When the volumes of sediments delimited by stratigraphyc markers are compared with the number of wells that penetrated these horizons, it comes out that some units are not as explored as would have originally appeared. This is especially true for the 1st megacycle. possible future exploration objects are cross-bedded Middle Miocene biocalcarenites and lateral equivalents of basinal coarse clastics-breccias but located on the margins of structural depressions (formed there by destruction of Triassic dolomite-limestone sediments of Slavonian Mts. and their neighbouringregions in the Drava and Sava depression) as well as the Neogene clastic sediments located underneath older overthrusted rocks.

Definiranje naftnih sistema provedeno je za područje južnog, graničnog dijela Panonskog bazena i za hrvatski dio Jadranskog podmorja.

In the S part of the Pannonian Basin, in Croatia, sediments are containing oil and gas in a number of small reservoirs. Studies have shown indications of source rocks in whose kerogen is deposited.

A study of geological structures, geophysical research and geochemical analyses realised in the Sava depression of Croatia