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EN
A history of landscape development in the Russian part of the Neman Delta area during the Holocene, with an emphasis on the formation of forests and wetlands, is deduced based on pollen analysis, radiocarbon dating, a field topography survey, and macrofossil analysis of peat deposits in a coastal mire, the Koz’ye Bog. Several 1,000-2,000-year time lags in vegetational development were revealed here, though they have not been recorded for other landscapes in the Kaliningrad Region and the adjacent areas in the southeastern Baltic. The causes are still not completely clear, but they presumably related to some of the regional patterns of climate development and the submergence of the area during the second Littorina transgression (7,500-7,000 cal. yr BP). It is established that cryophilic open tundra-like vegetation existed here not only in Late Glacial time (Younger Dryas) but up to the mid-Boreal (9,700-9,500 cal. yr BP). A transition from the open landscapes of the Late Glacial to birch and then pine forests occurred here 9,700-8,700 cal. yr BP, whereas the expansion of thermophilic broadleaf species of the nemoral (temperate) association (Quercus, Ulmus, Tilia, Corylus) was recorded only in the period 6,400-3,500 cal. yr BP. Peak expansion of Alnus occurred here only in the late Subboreal (3,500-2,700 cal. yr BP), while in adjacent areas it reached its maximum as early as the Atlantic. The general vegetation dynamics in this area during the Late Glacial and the Holocene could be referred to as a transition from the dominance of pine forests to a wide dispersal of alder carrs. This environmental shift was caused not only by climatic factors but probably also due to the transformation of the hilly coastal terrace into a low-lying plain landscape after flooding during the transgressions of the Baltic.
EN
The creation of multimodal transport structures of United Europe is focused on development system of all transportation network based on a multimodal principle. One of elements of this structure is the river transport. Work is devoted the analysis and offers on development and inclusion of river fleet of Poland in the general scheme of the multimodal freight traffic as much as possible approached to its geographical position and environmental conditions, as territories of the Baltic region.
EN
For lithostratigraphic successions of the lower Paleozoic strata in the Polish part of the Baltic Sea between the Slupsk Block and Courland Block, assessment of petrophysical properties was carried out with the use of mercury porosimetry and well logging results. The porosimetric measurements allowed to determine critical rock parameters and to distinguish genetic types of reservoirs. To complete the information on reservoir parameters, available well logs were used. The logs allowed identification of Cambrian strata in boreholes and the distinguishing of several lithostratigraphical units. Results of the porosimetric measurements demonstrated the strongly heterogeneous character of the pore space in the Cambrian rocks, with generally very weak reservoir properties. Fractured and porous-fractured rock space is a principal feature here. Well log anomalies confirmed the diversified lithological development of the Cambrian profile and the somewhat better reservoir parameters of rocks of the Paradoxides paradoxissimus Superzone and the shaly character of the Eccaparadoxides oelandicus Superzone. From the point of view of volumes of potential hydrocarbon accumulations, the capacity of the Cambrian deposits is low, but this is a basic feature of reservoir rocks with fractured and fractured-porous space.
EN
The Polish part of the Baltic region is located within the contact zone between two large geological units: the Precambrian platform and the Paleozoic platform. It comprises the Polish sector of the southern Baltic Sea and the adjacent onshore part of Northern Poland (Western and Eastern Pomerania). The fundamental geological pattern is defined by the Teisseyre-Tornquist Zone, separating the East European Craton from the Paleozoic platform. As a result of exploration activity in the onshore Pomerania region, four oil fields in Cambrian sandstones, seven gas fields in Carboniferous sandstones, six gas fields in Rotliegend sandstones, and eleven oil fields within the Zechstein Main Dolomite horizon have been discovered. The petroleum play of the southern Baltic Sea region and adjacent areas must be considered separately for Eastern and Western Pomerania. In the Peribaltic Syneclise we can only take into consideration organic matter appearing in lower Paleozoic rocks but their geothermal history refers to the period from the Vendian up to the recent. The present extent of the "oil window" in the Upper Cambrian rocks is mainly restricted to the offshore area. Reservoir properties of the "gas window" Cambrian rocks are rather low due to intensive diagenetic processes. Acquisition of gas should be possible by processes of hydraulic stimulation (tight gas). Lower Paleozoic rocks rich in organic matter (Ordovician and Silurian), especially in the border zone of the EEC (Ro >>gt; 1.3%), could be an area of unconventional gas fields (shale gas). The Western Pomerania petroleum play shows two separate source rocks units. The older one embraces Carboniferous deposits with organic matter of terrestrial origin and generated gases accumulated in the Rotliegend and Carboniferous traps. The second petroleum system is located within the carbonates of the Zechstein Main Dolomite (Ca2). This is a closed system, meaning that the source rocks are at the same time the reservoirs sealed by Zechstein evaporates. Hitherto discovered hydrocarbon deposits in the Polish part of the Baltic region have confirmed good perspectives regarding oil and gas hydrocarbon zones. New, conventional and unconventional discoveries remain possible.
EN
We have examined 21 samples of crude oils accumulated in the Middle Cambrian sandstone reservoirs from the Polish part of the Baltic region. All the crude oils have similar parameters and indices, which suggests generation from the same source rock. Evaporative fractionation and biodegradation processes were detected in oil collected from the B4-N1/01 borehole. All crude oils have high gravities and low-sulphur contents, less than 0.3 wt.%, which suggests that their source rock contained low-sulphur kerogen deposited in a clastic environment. A low asphaltenes content (below 0.3 wt.%) and high saturate/aromatic hydrocarbon ratios indicate long migration distances or high thermal maturities. The longest migration distance was probably attained by oils from the arnowiec and B16 deposits. The biomarker data indicate an algal origin for the source organic matter deposited under conditions of clastic sedimentation. The stable carbon isotope data support this observation. The maturity of the oils analysed varies from ca. 0.75 to ca. 1.05% on the vitrinite reflectance scale. Unlike the B6, B16, Dbki and arnowiec accumulations, oils from the B3 and B4 accumulations reveal the lowest maturity.
EN
The burial history, thermal maturity, and timing of hydrocarbon generation of four source rock successions were modelled: the Middle Cambrian, the Upper Cambrian-Tremadocian, the Upper Ordovician (Caradocian) and the lower Silurian (Llandovery and Wenlock). The 1-D modelling was carried out in profiles of eight boreholes throughout the western Baltic region. Four selected boreholes are located offshore: A8-1/83, A23-1/88, B6-1/82 and B4-2A/02, and four onshore: Bialogóra 3, Dbki 3, Leba 8 and arnowiec IG 1. The thermal maturity of source rocks is the highest in the deeper buried western part of the basin and decreases from the west to the east and north-east towards the basin margins. The lower Paleozoic source rocks contain oil-prone Type-II kerogen. The modelling indicated that the onset of petroleum generation from the lower Paleozoic source rocks occurred from the Early Devonian through the early Carboniferous period. The peak of hydrocarbon generation took place from the Late Devonian to the Tournaisian. The majority of hydrocarbons generated were expelled during the latest Early Devonian and Carboniferous, and oil has not been expelled from source rock only in the eastern offshore part of the basin.
EN
The quantity, genetic type and maturity of organic matter dispersed in the Lower Cambrian to the uppermost part of the Silurian (Pridoli) sequence of the Polish part of the Baltic region was determined based on the results of geochemical analyses of a total of 1377 rock samples collected from 38 onshore and offshore boreholes. The best source rocks were found in the Upper Cambrian-Tremadocian succession where present and initial total organic carbon (TOC) contents are up to ca. 18 and 20 wt.%, respectively. Caradocian (Ordovician) strata can be considered as an additional source of hydrocarbons. In the individual boreholes median present and initial TOC contents vary from 0.5 to 3.3 wt.% and from 1 to 6 wt.%, respectively. The Llandovery (Silurian) strata reveal moderate and locally high hydrocarbon potential of the source rocks. The present TOC content reaches locally 10 wt.% (usually 1-2 wt.%). Another source of hydrocarbons can be clayey intercalations within the Middle Cambrian strata. Their organic matter content rarely exceeds 1 wt.%, being often a result of advanced organic matter transformation. In all lower Paleozoic strata investigated from the Polish part of the Baltic region oil-prone, low-sulphur Type-II kerogen occurs, deposited in anoxic or sub-oxic conditions. The maturity of all source rocks changes from the initial phase of the low-temperature thermogenic processes in the northeastern part to the overmature stage in the southwestern part of the study area.
EN
The present-day structural pattern of the Baltic Depression developed due to superimposition of three main deformation phases: syn-Caledonian (after the Silurian), syn-Variscan (at the end of Carboniferous and beginning of Permian) and syn-Alpine (latest Mesozoic or earliest Cenozoic). The major restructuring of the area occurred as a result of syn-Variscan deformation that took place in latest Carboniferous and earliest Permian times. Most of the faults developed or became reactivated probably at that time. Syn-Alpine deformation manifested itself relatively weakly, mainly by reactivation of some pre-existing faults.
EN
Determining kinetic parameters for oil generation from a source rock by hydrous pyrolysis requires a considerable amount of sample (kilograms) and laboratory time (several weeks). In an effort to circumvent these requirements, hydrous-pyrolysis (HP) kinetic parameters for oil generation from Upper Cambrian and Tremadocian source rocks of the Baltic region are estimated by two methods: (1) organic sulfur content in kerogen and (2) HP experiments conducted at 330 and 355°C for 72 h. Estimates for the Upper Cambrian source rocks based on organic sulfur contents gave activation energies from 47 to 56 kcal/mole and frequency factors from 1.156 ' 1025>/sup> to 1.078 ' 1028 m.y.-1 . Tremadocian source rocks based on organic sulfur content gave estimated activation energies from 60 to 62 kcal/mole and frequency factors from 1.790 ' 1029 to 1.104 ' 1030 m.y.-1 . The estimates for the Tremadocian source rocks were less affected by thermal maturation because their low kerogen S/(S + C) mole fractions (< 0.018) remained essentially constant. Conversely, the higher kerogen S/(S + C) mole fractions (>>gt; 0.018) of the Upper Cambrian source rocks decreased with thermal maturation and resulted in overestimation of the kinetic parameters. The second method was designed to estimate kinetic parameters based on two HP experiments. The assumption that the maximum yield in calculating the rate constant at 330°C (k330°C could be determined by a second hydrous pyrolysis experiment at 355°C for 72 h proved not to be valid. Instead, a previously established relationship between Rock-Eval hydrogen index and maximum HP yield for Type-II kerogen was used to calculate k330°C from oil yields generated by the HP experiment at 330°C for 72 h assuming a first-order reaction. HP kinetic parameters were determined from relationships between k330°C and the HP kinetic parameters previously reported. These estimated HP kinetic parameters were in agreement with those obtained by the first method for immature samples, but underestimated the kinetic parameters for samples at higher thermal maturities. Applying these estimated HP kinetic parameters to geological heating rates of 1 and 10°C/m.y. indicated that the Upper Cambrian source rocks would generate oil notably earlier than the overlying Tremadocian source rocks. This was confirmed in part by available data from two neighboring boreholes in the Polish sector of the Baltic.
EN
The burial history and thermal evolution of the western part of the Baltic region was reconstructed by means of 1-D modelling for eight boreholes penetrating the lower Paleozoic succession. The Neoproterozoic rifting presumably caused elevation of heat flow, while Cambrian to Mid Ordovician post-rift thermal sag of the Baltica passive margin led to systematic decrease of heat flow with time. Development of the Late Ordovician to Silurian flexural foredeep of the Caledonide collision zone was associated with intensive subsidence, a high rate of sediment deposition and rapid burial of the Upper Cambrian and/or Tremadocian, Upper Ordovician and lower Silurian source rocks, presumably sufficient for the early stage of oil generation. After post-Caledonian Early Devonian uplift, the western Baltic region was subject to Early Devonian to early Carboniferous subsidence and deposition, leading to further burial of the source rocks. Together with elevated heat flow, characteristic of the Variscan broad foreland, this caused further source rocks maturation and hydrocarbon generation. Late- to post-Variscan uplift and erosion (late Carboniferous to late Permian) resulted in complete removal of the Middle Devonian to lower Carboniferous strata and development of the major regional unconformity. During late Permian to Cretaceous time the western part of the Baltic region constituted an eastern flank of the Polish Trough, with the main phases of subsidence and burial during late Permian-Early Triassic time, related to rifting in the Polish Trough, and during Late Cretaceous time, related to the compressional regime. Maturity profiles in boreholes from the vicinity of the studied boreholes indicate the presence of a late Mesozoic (Late Cretaceous?) positive thermal event, causing further maturation of the source rock.
EN
2-D modelling of hydrocarbon generation, expulsion, migration and accumulation processes was carried out for the four (Middle Cambrian, Upper Cambrian-Tremadocian, Caradocian and Llandovery) source rock horizons. The petroleum potential of these source rocks is different, the highest being observed in the Upper Cambrian-Tremadocian horizon and the lowest in the Middle Cambrian one. The maturity of organic matter within these source units increases from the north-east to the south-west of the Polish part of Baltic region. The petroleum generation from these source rocks was highest in the Darlowo and Slupsk blocks as well as in the onshore part of the Leba Block. Expulsion took place mainly from the Upper Cambrian-Tremadocian source rocks and these rocks sourced almost all hydrocarbons accumulated within the Middle Cambrian sandstone reservoirs. Migration of hydrocarbons proceeded along fault zones. Almost all petroleum processes in the study area took place between the end of the Pridoli and the end of the Carboniferous. Moreover, during the Permian and the Mesozoic, part of the hydrocarbons remigrated within the reservoir. This process changed the setting and the volume of hydrocarbon accumulations. It was caused by the tectonic rebuilding of the basin and, in most cases, it led to the modification of accumulation range or to the dispersion of hydrocarbons.
PL
W artykule przedstawione zostały rozważania z zakresu możliwości zastosowania koncepcji sieciocentryczności na obszarach morskich Rzeczypospolitej Polskiej. Dokonano tego po analizie idei tej koncepcji oraz na tle systemu bezpieczeństwa istniejącego w Regionie Bałtyckim.
EN
The paper considers possibilities of using the network centrik concept in maritime areas of Poland. The idea is analysed taking intoconsideration the existing security system in the Baltic Region.
EN
The expected influence of variability in atmospheric aerosol profiles on retrievals of aerosol optical thickness (AOT) from NOAA AVHRR measurements is analysed. In particular, the bias in the AOT retrieval due to the assumption of a climatological aerosol profile in the retrieval algorithm is studied. The bias is defined as the difference between AOT retrieved with an algorithm using a climatological aerosol profile, and the actual AOT employed in the calculations of radiances at the top of the atmosphere (TOA). The TOA radiances are simulated by means of the MODTRAN code for different aerosol profiles. Atmospheric conditions and solar and satellite angles used in the bias simulations are typical of the Baltic region. In the simulations, the maximum absolute value of the bias amounts to nearly 40% in channel 2 and 14% in channel 1 of AVHRR.
EN
The paper discuses some peculiarities of usage in the Baltic region of satellite navigation system (GPS) and Eurofix service with application to UAV control in UAV regional flights. Spatial decorrelation reduces the efficiency of DGPS corrections and the usefulness of installing some additional DGPS stations (but not Eurofix) in the Baltic region is considered.
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