The paper presents new data on the Miocene development within the Upper Silesian Coal Basin. The Miocene succession of the study area is characterized by high thickness and highly variable lithology. In the Miocene sediments of the studied area, the presence of organic matter in the form of a coal layer, coal crumbs, and dispersed organic matter has been found. The research focused mainly on the analysis of organic matter in terms of its origin, degree of coalification, and depositional environment. The degree of coalification of organic matter was determined by the huminite/vitrinite reflectance. The hard brown coal layer with a thickness of about eight meters was identified within the Kłodnica Formation. Based on the textural properties and degree of coalification, brown coal was classified as dull brown coal and bright brown coal. Organic matter in the form of coal crumbs and dispersed organic matter were found within a package clastic sedimentary. On the basis of petrographic analysis, two types of allochthonous organic matter with different degrees of coalification were identified. The coal clasts are mainly of Carboniferous origin, while the Miocene redeposited brown coal grains dominate within the dispersed organic matter. Coal fragments and dispersed organic matter derived from the Miocene brown coal were also found within the black claystones. The study of organic matter of the Miocene sediments in the Upper Silesian Coal Basin showed both its autochthonous and allochthonous origins.

In this paper we describe a fossil graben and associated normal faults and joints. The graben occurs in the section of the Vistulian (Weichselian) and Holocene sediments in an archaeological excavation site at Brzezie, in the central part of the Polish Carpathian Foredeep (Wieliczka-Gdów Upland, western part of the Sandomierz Basin). Normal faults strike mostly NNE-SSW and dip steeply about 65 - 850. Some of them, namely master normal faults, bound the fossil graben. The joints form orthogonal pattern and are closely spaced close to the faults. They developed simultaneously with faulting. Normal faulting took place during the Vistulian - Mesoholocene (Neoholocene?) time, according to age of the archaeological artefacts which were found in the faulted sediments. The faulting was probably finished during the Neolithic or even later, during the Bronze Age. The NNE-striking normal faults connected with graben formation could have been produced by reactivation of a NE-striking sinistral regional fault in the basement.

The results of drill stem tests made on the autochthonous Miocene deposits of the Upper Badenian - Lower Sarmatian age in the Carpathian Foredeep were analyzed. Reservoir tests were performed in open and cased holes, where inflows of formation water of varying saturation degree and sometimes contaminated with drilling mud filtrate, were observed. A total of 58 intervals, geophysically qualified as gas-bearing, were analyzed. Statistical analysis methods were used for determining the influence of the formation depth on the depth of deposition of the Miocene, and also dependence of initial back-pressure exerted on the reservoir during DST, on the depth of deposition of the reservoir. No correlation was found between water flow rate and initial differential pressure. A satisfactory correlation was obtained between hydrostatic pressure of water cushion in the tubing string and reservoir pressure for selected 22 the Miocene intervals in the Dębica region. In this region the pressure quotient php/pz broadly ranged between 0.05 and 0.57. Another correlation was noted between initial back-pressure and a depth at which pressure was measured and initial back-pressure, and formation water flow rate. The regression equations determined with statistical methods can be used for predicting values of formation pressure, initial value of back-pressure, formation water flow rate and initial differential pressure during DST. On this basis technological parameters of successive reservoir tests can be determined for in the analyzed area of the Carpathian Foredeep, particularly in the Dębica region.

Neotectonic structures of the Upper Silesia that originated during the last 5 Ma (Pliocene and Quaternary) overlap Miocene grabens and horsts of the Carpathian Foredeep. They had been reactivated in Pliocene as an effect of the young Alpine uplift of the Carpathian Foredeep. It is postulated that ice-sheet derived compaction of a thick Miocene deposits was the most significant agent of the development of neotectonic depressions. Glacioisostasy of mobile bedrock structures was presumably also an important component of vertical movements. The amplitude of neotectonic movements is estimated to 40-100 m, basing on DEM map analysis, analysis of sub-Quaternary structural maps, and the Pleistocene cover thickness. The present-day tectonic phenomena are generated by mining-induced seismicity. These are connected with stress relaxation in the deep bedrock thrust zones of the Upper Silesian Coal Basin.

In this study some of the experimental results of water shut-off treatments in oil and gas production wells were presented. The effect of water saturation of Miocene rocks of the Carpathian Foredeep on the relative permeability to gas was analyzed. Also, wide review of the worldwide publications from the point of view of the results obtained in water shut-off treatments in oil and gas formation was presented. Based on experimental results efficiency of relative permeability modification of sandstone from Szydłowiec to brine and nitrogen by four selected chemicals polymers and microgels was evaluated. Experimental results indicated that trend changes of permeability modification strongly depends on the fluid used in the RPM treatment. Moreover, efficiency of permeability modification to brine depends on flow rate of brine through the core - the lower brine flow rate the higher efficiency of the RPM treatment. RPM product number 1 caused significant loss of permeability to brine ca. 60% and slight permeability modification to gas ca. 18%. This permeability change to brine and gas was obtained by modification of formation wettability what affects well productivity. In the case of product number 2 which is based on microgels technology, also significant modification of selective permeability to brine was observed. Loss of permeability to brine was in the range of 65 to 90% while to gas ca. 50%.