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EN
We applied the detailed structural analysis to 394 outcrops in the southern and northern metamorphic cover of the Karkonosze Intrusion. We recognised five generations of fold structures: F1 -poorly preserved tight intrafoliation folds; F2 - the most common generation, with the whole variety of fold geometries, W-E and WSW-ENE-oriented fold axes in the northern contact zone, and W-E and WNW-ESE-oriented fold axes in the southern contact zone; F3 - chevron folds; F4 - kinkfolds observed only in the Stara Kamienica schist belt; and F5 - wide open folds, locally transformed into monoclinal kinkfolds, probably formed during the Variscan intrusion of the Karkonosze pluton. Similarity observed in the structural style in the northern and southern contact zones prove that these lithostratigraphic units had formed a single unit - the Izera-Kowary Unit - and had undergone the same deformational stages before the Karkonosze granitoid intrusion took place.
EN
The Kaczawa Mountains along with the Kaczawa foothill comprise a complicated geological unit that is called the Kaczawa metamorphic (Sudetes, SW Poland). The aim of our work was to identify the iron-bearing minerals in samples of basalts and pillow lavas from the Kaczawa metamorphic using 57Fe Mössbauer spectroscopy. Based on the preliminary results, the Fe3+/Fe2+ ratio in the samples was determined.
EN
This research presents soil gas 222Rn and 220Rn concentrations measured at 17 locations in the Izera Massif of southwest Poland. The average 222Rn concentrations at sampling depths of 10, 40 and 80 cm were 8, 78 and 224 kBq m–3, respectively. The average 220Rn concentrations for the same depths (10, 40 and 80 cm) were 6, 10 and 13 kBq m–3, respectively. Profiles of the concentrations versus depth can be fitted by exponential, linear and polynomial functions for soils developed on fault zones, above uranium mineral deposits, and above faulted uranium deposits, respectively. Soils developed on bedrock without fault zones or uranium mineralisation exhibit concentrations that follow a power function with an exponent of p<1.
EN
The paper presents the results of the laboratory gamma-ray measurements of six igneous rocks from the Opava Mountains. The Opava Mountains are located in the Eastern Sudetes and represent their furthest eastern range. They run almost latitudinally along the Polish border with the Czech Republic. The Opava Mountains are mostly situated in the Czech Republic. Only a small fragment between Głuchołazy in the west and Prudnik in the east is situated in Poland (Janeczek et al. 1991). The study area is built of rocks of different ages and lithologies. The Opava Mountains belong to the western part of the Upper Silesia Block, which together with the Brno Block form a structure that is called the Brunovistulicum. The mountains consist of five structural stages: the Žulova Massif, the Desna Series, the Vrbno Series, the Andělská-Hora Formation and the Horn-Benešov Formation, which run longitudinally (Żaba et al. 2005). The activities of naturally occurring radionuclides were measured using a portable GX3020 gamma-ray workstation. The system is based on a high-purity germanium (HPGe) detector with a 32% relative efficiency and energy resolutions of 0.8 keV at 122 keV and 1.7 keV at 1330 keV. The activity concentrations of 40K varied from 519 Bq∙kg−1(paragneiss, Głuchołazy/Mikulice) to 1559 Bq∙kg−1(weathered granite, Sławniowice), while those of 228Ac (232Th series) from 7.2 Bq∙kg−1(weat hered granite, Sławniowice) to 70.6 Bq∙kg−1 (migmatitic gneiss, Nadziejów). The activities that were associated with 226Ra (238U series) ranged from 5.5 Bq∙kg−1(weathered granite, Sławniowice) to 52.2 Bq∙kg−1 (gneiss, Kamienna Góra). The measured activity concentrations were compared with the average activity concentration of 40K, 228Ac (232Th) and 226Ra (238U) for similar types of rocks reported in the world specialist literature. The average value of the activity concentrations of 40K for granites and gneisses equals 1000 Bq∙kg−1 (Van Schmus 1995, Eisenbud & Gesell 1997), which means that the measured value of granite in the Sławniowice quarry is significantly higher than the average one, whereas the activity concentration of paragneiss is almost two times lower than the average value of similar types of rocks. The activity concentrations of 228Ac (232Th) and 226Ra (238U) in measured rocks are comparable to the average values (70 Bq∙kg−1 and 40 Bq∙kg−1 respectively (Van Schmus 1995, Eisenbud & Gesell 1997). Only the activity concentrations of granite in the Sławniowice quarry are considerably lower than the average values for the typical ones because it is strongly weathered. The aim of this paper is to show the first experimental data concerning the activity concentrations of primordial radionuclides in the igneous rocks in the Opava Mountains.
EN
The Precambrian basement and Lower Paleozoic (Cambrian–Ordovician) sedimentary cover in the eastern part of the Upper Silesian Block (Brunovistulicum), known only in boreholes, is presented, and their palaeogeographic, facies and palaeotectonic development is discussed. The former is characterized by a heterogeneous structure that consists of Archean-Lower Proterozoic and Neoproterozoic rocks of different lithologies and origins, and the latter is almost exclusively represented by marine, transitional and terrestrial siliciclastic rocks. In contrast to the neighbouring region of the western part of the Małopolska Block, the siliciclastic sedimentation took place during the Early and Middle Cambrian in this area, however, the Ordovician deposits were encountered in several boreholes and no Silurian rocks have been reported in the northern part of this region. The authors present the most probable model of sedimentation, tectonics and origin of the geological structure of the Lower Paleozoic sedimentary cover in the Upper Silesian Block, define research problems, and justify the need for new drillings. Based on the geological and structural analysis of the depth to the top surface of the Lower Paleozoic, they define the optimal location for three 1500 m deep boreholes to solve the basic research problems.
EN
A spectacular epigenetic silicification was encountered in the Oxfordian bedded limestones exposed in the Sokole Hills situated in the Kraków-Częstochowa Upland. The main epigenetic mineral is microcrystalline quartz accompanied by minor goethite, hematite, barite, galena and sphalerite. Locally, the mineralized limestones reveal Pb and Cu contents exceeding over 150 times the background values of these metals in unmineralized limestones. The epigenetic mineralization of the bedded limestones was probably a two-stage process. During the first, Early Cretaceous stage, silicified limestones formed at the erosional surface of a denuded carbonate complex. Such silicification greatly limited the progress of the first karstification phase of the Upper Jurassic carbonates initiated in the Hauterivian. The sources of silica accumulated in the limestones were descending solutions enriched in silica derived from the weathering zone. This silicification affected the topmost part of the Upper Jurassic massive limestones and the deeper portions of the bedded limestones along the fracture systems and stylolites. Early Cretaceous tectonic activity generated new dislocations and re-opened the existing faults, which were subsequently filled with permeable Albian quartz sands. These openings became the migration pathways for ascending, warm, relict, sulphide-carrying hydrothermal solutions at the second formation stage of the epigenetic mineralization. The newly supplied silica from the Albian sands precipitated on the silicified limestones and, as concentric rims, on brecciated, early diagenetic cherts. The second-stage mineralization proceeded under phreatic conditions, presumably close to a fluctuating mixing zone of ascending, warm hydrothermal solutions and descending cold groundwaters. The brecciated cherts acting as silica crystallization nuclei indicate that the last mineralization stage probably followed the final phase of Cenozoic faulting.
EN
The paper describes a workflow (and a resulting 3D geological model), developed for detailed 3D modeling of coal deposits in the "Knurów-Szczyg³owice" Underground Coal Mine in the Upper Silesian Coal Basin. The model covers 20 sq. km (4 5 km) and integrates data from various sources: mainly coal seam mining maps and lithological borehole profiles, but also auxiliary sources like legacy cross-sections and structural maps. High grid resolution and relatively small uncertainties allow future testing of the model's application in industry-related issues such as mining subsidence prediction or underground coal gasification.
EN
In situgamma-raymeasurements of fourigneousrocksweretaken in the Opava Mountains (EasternSudetes, Poland). The activity of naturallyoccurringradionuclides was measuredusing a portable GX3020 gamma-rayspectrometryworkstation. The activityconcentrations of 40K varied from 914 ± 17 Bqkg-1 (gneiss, Kamienna Góra) to 2019 ± 37 Bqkg-1 (weatheredgranite, Sławniowice), whilethose of 232Th from 7.5 ± 0.6 Bqkg-1 (weatheredgranite, Sławniowice) to 68 ± 0.9 Bqkg-1 (migmatiticgneiss, Nadziejów). The activitiesassociated with 238U decayseriesranged from 10 ± 0.4 Bqkg-1 (weatheredgranite, Sławniowice) to 62 ± 1.6 Bqkg-1 (gneiss, Kamienna Góra). The resultswill be used in compilingRadiological Atlas of the Sudetes.
EN
The network of faults and joints within the Mesozoic, Miocene and Pleistocene–Holocene formations was studied in the Rio Colca valley, in the Pinchollo–Lari–Maca area (Central Andes, southern Peru). A complex, multi-phase development of these structures was revealed. The results show that the structural framework of the Rio Colca valley consists of WNW–ESE and NE–SW faults, and a few W–E faults. The strike of the most common fault sets is approximately parallel (longitudinal) or perpendicular (transverse) to the W–E oriented strike of stratification surfaces in the Mesozoic sedimentary series and the W–E fold macro-structures, developed in these strata. Diagonal faults and joints are less common, although at some localities they are numerous. The recurrence of major fault systems throughout the Mesozoic and Miocene series and the Pleistocene–Holocene (mainly colluvial) deposits is proof of recent, tectonic activity in the study area. The recent faulting has led to the development of a system of distinct, primary fault scarps, tectonic grabens and horsts, as well as open fissures, which are well marked in the surface morphology, and in many cases have not yet been eroded.
EN
The Ngorongoro Crater, as the largest unflooded and not destroyed volcanic caldera on Earth, is one of the major geotouristic attractions of East Africa. Unique on the global scale richness of wildlife, exotic cultures of indigenous people and specific position of the Crater within the East African Rift System, each year attracts thousands of tourists eager for an unforgetable experience. Their number continues to growfrom year to year, reaching the value of nearly half a million visitors within the last few years. Constantly developing tourism industry, besides many advantages, also causes a number of risks, both for the world of living nature and inanimate nature objects, as well as for the local population. In 1959, recognizing the unique and special touristic and geoeducative values of this location, the Ngorongoro Conservation Area (NCA) was established. Almost twenty years later, in 1978, the area was included in the UNESCO World Cultural and Natural Heritage List. Furthermore, within the Ngorongoro Conservation Area as well as in its immediate neighborhood there are many objects that also deserve to be called geotouristic attractions, such as: Olduvai Gorge, Crater Olmoti, Crater Empakai and Oldoinyo Lengai volcano. In a relatively short distance from the Crater also the highest mountain in Africa - the Kilimanjaro volcano and the biggest active volcano of this continent, Meru, are located.
PL
Krater Ngorongoro, jako największa niezalana i niezniszczona kaldera wulkaniczna na Ziemi, stanowi jedną z najważniejszych atrakcji geoturystycznych Afryki Wschodniej. Wyjątkowe bogactwo przyrody ożywionej, egzotyka kultury ludności autochtonicznej oraz unikalna pozycja krateru w obrębie wschodnioafrykańskiego systemu ryftowego, przyciąga każdego roku ogromne rzesze turystów żądnych niezapomnianych przeżyć. Ich liczba każdego roku stale rośnie, osiągając w ostatnim okresie prawie pól miliona odwiedzających. Wzmożony i stale nasilający się ruch turystyczny ma wiele zalet, lecz powoduje również szereg zagrożeń, zarówno dla świata przyrody ożywionej, jak i nieożywionej, a także dla ludności lokalnej. W roku 1959, w uznaniu szczególnych walorów turystycznych i geoedukacyjnych krateru i jego okolicy ustanowiono tam Obszar Chroniony Ngorongoro (NCA). W roku 1978 obszar ten wpisano także na Listę Obiektów Światowego Dziedzictwa Kulturowego i Przyrodniczego UNESCO. Zarówno na Obszarze Chronionym Ngorongoro, jak też w jego najbliższym sąsiedztwie znajduje się bardzo wiele obiektów, które ze wszech miar zasługują na miano atrakcji geoturystycznych; należą do nich m.in.: wąwóz Olduvai, krater Olmoti, krater Empakai bądź wulkan Oldoinyo Lengai. W stosunkowo niewielkiej odległości od krateru Ngorongoro znajduje się najwyższa góra Afryki - wulkan Kilimandżaro oraz największy czynny wulkan tego kontynentu - Meru.
EN
The caldera of an extinct Ngorongoro volcano is the largest unflooded and not destroyed type of this form on Earth. The depression itself occupies an area of nearly 300 km2, while the Crater walls tower a few hundred metres (400-610 m) above the floor of the caldera. Almost all typical for East Africa plants and animals, as well as rare, endemic and often endangered species can be observed in the crater. The unique richness and diversity of natural world of the Ngorongoro Crater is caused exceptionally by favourable weather and hydrological conditions. These factors depend on local conditions, associated with significant relief of this area. Probably, the most important is the richness of the Ngorongoro Crater in water. There occur springs, perennial and seasonal rivers, marshes, swamps, as well as reservoirs of fresh and salty water. Essential is also the presence of the local autochthonous population of the Maasai people, which raises the attractiveness of that localization adding so important cultural values. Due to its unique natural and touristic values, the Ngorongoro Conservation Area (NCA) has been established in 1959. The area was also included into the UNESCO World Cultural and Natural Heritage List. This paper presents only the geographical setting of the Ngorongoro Crater, which should be understood as its morphology, hydrological and climatic conditions, wildlife and indigenous local people.
PL
Kaldera wygasłego wulkanu Ngorongoro stanowi największą niezalaną i niezniszczoną tego typu formę na Ziemi. Zagłębienie zajmuje obszar prawie 300 km2, zaś ściany krateru wznoszą się na wysokość nawet 600 m ponad jego dno. W jego obrębie można obserwować niemalże wszystkie, typowe dla Afryki Wschodniej rośliny i zwierzęta, a także gatunki rzadkie, endemiczne, częstokroć zagrożone wyginięciem. Bogactwo świata przyrody ożywionej cechujące krater Ngorongoro jest spowodowane wyjątkowo korzystnymi warunkami klimatycznymi i hydrologicznymi. Elementy te są w znacznym stopniu uzależnione od warunków lokalnych, związanych z występującymi na tym obszarze deniwelacjami terenu. W obrębie kaldery Ngorongoro występują wody słodkie i słone, zarówno płynące, jak i tworzące stałe zbiorniki o różnym charakterze. Oprócz walorów typowo przyrodniczych tego obszaru na szczególną uwagę zasługuje autochtoniczna ludność lokalna Masajów. Jej obecność podnosi w znacznym stopniu atrakcyjność analizowanego obiektu, wnosząc walory kulturowe. Ze względu na unikalne walory przyrodnicze i turystyczne w obrębie kaldery oraz na terenach przyległych powstał w 1959 roku Obszar Chroniony Ngorongoro (NCA) o charakterze parku narodowego. Rejon ten został następnie wpisany na Listę Światowego Dziedzictwa Kulturalnego i Przyrodniczego UNESCO.
EN
The Ngorongoro Crater is the largest unflooded and not destroyed collapse volcanic caldera of the shield volcano on Earth. It attracts many visitors each year not only because of the undoubted wealth of the wildlife and breathtaking views, but also due to the geotouristic attractiveness of this definite location. The Crater is in fact a specific example of geological processes, relevant to the development of planet Earth. In a relatively small area one can observe rocks of different types and ages: Precambrian igneous and metamorphic rocks, volcanic rocks formed in the Pliocene, Pleistocene, and even nowadays, as well as sedimentary rocks, up to those currently forming within the caldera floor. The origin and development of the Ngorongoro volcano, and lately caldera, is closely related to the activity ofrifting processes occurring along the Gregory Rift, belonging to the East African Rift System. It represents one of the three arms of the Afar triple junction associated with the located here hotspot. Due to the geotouristic attractiveness, as well as a richness of living nature and archaeological sites with discoveries of our ancestors, which illustrate an important stage in the history of mankind, the area of the Ngorongoro Crater was designated a UNESCO World Cultural and Natural Heritage Site.
PL
Krater Ngorongoro to największa tak dobrze zachowana (niezalana wodą i niezniszczona) kaldera zapadliskowa wygasłego wulkanu tarczowego na Ziemi. Przyciąga ona każdego roku nieprzebrane rzesze turystów nie tylko ze względu na zapierające dech w piersiach widoki oraz niewątpliwe bogactwo flory, a w szczególności fauny, lecz również z uwagi na swą wyjątkową atrakcyjność geoturystyczną. Krater ten stanowi bowiem szczególny przykład wyjątkowo istotnych dla rozwoju Ziemi procesów geologicznych. Na stosunkowo niewielkiej powierzchni można obserwować bardzo różnorodne skały: magmowe i metamorficzne wieku prekambryjskiego, wulkaniczne powstałe w pliocenie, plejstocenie i w czasach współczesnych, a także różnowiekowe utwory osadowe. Powstanie i rozwój wulkanu, a następnie kaldery Ngorongoro jest ściśle związany z aktywnością procesów prowadzących do rozwoju ryftu Gregory'ego, stanowiącego segment wschodnioafrykańskiego systemu ryftowego. Należy on do jednego z trzech ramion trójzłącza Afaru, ściśle genetycznie związanego z ewolucją znajdującej się na tym obszarze plamy gorąca. Z uwagi na swą wyjątkową atrakcyjność geoturystyczną oraz bogactwo i różnorodność przyrody ożywionej, jak też unikatowe uwarunkowania antropogeniczne (archeologiczne odkrycia szczątków i śladów bytności naszych przodków dokumentujące ważny etap historii ludzkości) rejon ten został wpisany na Listę Światowego Dziedzictwa Kulturowego i Przyrodniczego UNESCO.
EN
New geological, geochemical and U-Pb SHRIMP zircon age data brought more information about basement units in subsurface of Southern Poland and SE Romania, which allows to revise and refine some earlier models in the framework of the break-up of the Rodinia/Pannotia supercontinent. In the Brno Block, Moravia, and in the Upper Silesia Block, three different terranes formed the composite Brunovistulia Terrane. The Thaya Terrane (low eNd(T)) of Gondwana (Amazonia) descent collided obliquely at 640–620 Ma with the Slavkov Terrane (moderate eNd(T)) composed of amphibolite facies metasediments and arc-related, mostly unfoliated granitoids which intruded at 580–560 Ma. At that time, back-arc rifting separated the couple Thaya–Slavkov (inherited zircons: 1.01–1.2, 1.4–1.5, 1.65–1.8 Ga) that drifted away from Gondwana until collision around 560–550 Ma with the Rzeszotary Terrane, the Palaeoproterozoic (2.7–2.0 Ga) crustal sliver derived from Amazonia or West Africa. At least these three units composed Brunovistulia, which occurred at low latitudes in proximity to Baltica as shown by palaeomagnetic and palaeobiogeographic data. Then Brunovistulia was accreted to the thinned passive margin of Baltica around its Małopolska promontory/proximal terrane. A complex foreland flysch basin developed in front of the Slavkov–Rzeszotary suture and across the Rzeszotary–Baltica/Małopolska border. The further from the suture the less amount of the 640–550 Ma detrital zircons extracted from the Thaya–Slavkov hinterland and the smaller eNd(T) values. In West Małopolska, the flysch contains mainly Neoproterozoic zircons (720–550 Ma), whereas in East Małopolska 1.8–2.1 Ga and 2.5 Ga zircons dominate, which resembles nearby Baltica. The basin infill was multiphase folded and sheared; in Up per Silesia prior to deposition of the pre-Holmia Cambrian over step. In Małopolska, the folded flysch series formed a large-scale antiformal stack with thermal anticline in its core marked by low-grade metamorphic overprint. In Central Dobrogea, Moesia, Ediacaran flysch also contains mainly 700–575 Ma detrital zircons which link the source area, likely in South Dobrogea with ca. 560 Ma granitoids, rather close with Gondwana. However, fauna in Lower Cambrian overstep strata shows Baltican affinity. Such features resemble Upper Silesia, thus Brunovistulia might have extended beneath the Carpathians down to Moesia. The other part of South Dobrogea with Palaeoproterozoic ironstones resembles Ukrainian banded iron formation. If true, the Baltican sliver would be incorporated in Moesia. Such a possibility concurs with the provenance data from Ediacaran flysch of Central Dobrogea, which points to uplifted continental block as a source of derital material. Our study supports an earlier proposition that at the end of the Neoproterozoic a group of small terranes that included Brunovistulia, Moesia and Małopolska formed the Teisseyre-Tornquist Terrane As semblage (TTA). In our model, a characterisistic feature of the TTA was a mixture of crustal elements that were derived from both Gondwana and Baltica, which gave rise to mutual collisions of the elements prior to and concurrent with the docking to Baltica in latest Ediacaran times. The presence of extensive younger covers and complex Phanerozoic evolution of individual members of the TTA impede the recognition of their Neoproterozoic history.
EN
Two large, regional tectonic units, represented by Małopolska and Brunovistulicum blocks (terrains) can be distinguished in the southern Poland. The Cracow–Lubliniec fault zone forms their border. They vary both in the structures of the Precambrian basement and the Paleozoic rock cover, which shows different paleogeographic-facies and paleotectonic development. They are separated from the neighboring tectonic units by immense deep fault zones. Archean and Early Proterozoic metamorphic rocks within the Rzeszotary horst (2.6–2.8 and 2.0 Ga) are the oldest formations building the Brunovistulicum basement. Farther to the west, Precambrian and Ediacaran anchimetamorphic siliclastics can be observed. Cadomian-Precambrian rocks (640–545 Ma), which outcrop only near Brno, occur south and west of them. In the western part of the Brunovisitulicum (theWestern Sudetes) Variscan orthogneiss occurs. The age of its protholite varies vastly; from approximately 1020 Ma through 680–570 Ma to approximately 520–500 Ma. Precambrian basement of the Brunovistulicum is heterogenic. Within the area of Poland, it is formed by two fragments of the crust, represented by Karelian and Early Karelian rocks of the Rzeszotary horst and Cadomian crystalline and anchimetamorphic rocks occurring west of Rzeszotary. Between them, two vast, connected together, magnetic maxima in the vicinity of Tychy and Jordanów can be observed in a magnetic field image delta Z. The origin of those anomalies is related to the occurrence of gabbro, diabase and/or ultrabasite (ophiolite) rocks. Referring to the earlier concepts, it may be currently assumed that the anomaly axis Tychy–Jordanów determines the course of the contact zone (ophiolite suture zone) between the two fragments of the crust of different ages, building the basement of Brunovistulicum: the Archean - Lower Proterozoic (Karelian) and the Upper Proterozoic (Cadomian) formations.
EN
The attempt to divide the Upper Silesian Block and the Małopolska Block into tectonic units has been based on a general map at scale of 1:1000000, without Permian-Mesozoic and Cenozoic strata. Cartographic, general and monographic works regarding formation of Precambrian basement of both of the blocks have been discussed and presented, and data concerning development of sedimentation, tectonics, and structure of the Paleozoic cover of the blocks were the background for the suggested division. The Upper Silesian Block is a part of a larger unit determined as the Brunovistulicum, which together with the Brno Block are entirely located within the borders of the Czech Republic. The Brunovistulicum and the Małopolska Block vary in formation of Precambrian basement and covering Paleozoic formations, what proves different paleogeographical-facial and paleotectonic development. Current data do not allow determining their southern range, where both units are within the range of the orogeny of the Outer Carpathians and quite possibly in the range of the Inner Carpathians. The boundary of the Brunovistulicum and the Małopolska Block along the part between Lubliniec and Cracow and farther to the vicinity of Bochnia and Nowy Sącz is relatively well defined and documented. It is a narrow Cracow-Lubliniec fault zone, approximately 500 m wide, cutting and moving all rock series of the Precambrian and the Paleozoic. The fault zone of the Odra River probably forms its NW continuation. The following tectonic units have been distinguished in the Upper Silesian Block: 1) Moravian-Silesian Fold-and-Thrust Belt, 2) Upper Silesian Fold Zone, 3) Upper Silesian Trough, 4) Bielsko-Biała Dome, 5) Rzeszotary Horst, 6) Liplas Graben. There is only one tectonic unit distinguished in the Małopolska Block-Kielce Fold Belt, dipping towards NW-SE, along the NE boundary of the block. Paleozoic formations building the unit represent thrust fault structure. In this case, the Kielce Fold Belt significantly varies from the other parts of the Małopolska Block, where Paleozoic formations build numerous small block structures.
PL
Praca prezentuje wyniki badań strukturalnych sieci uskoków i spękań w utworach mezozoiku i czwartorzędu przeprowadzonych w Dolinie Rio Colca w okolicy Pinchollo-Lari-Maca (Andy Peruwiańskie). Z przeprowadzonych badań wynika, że Dolina Rio Colca ma założenia tektoniczne i wykorzystuje niemal wszystkie występujące na analizowanym terenie zespoły nieciągłości, ze szczególnym uwzględnieniem uskoków o przebiegu WNW-ESE, NE-SW oraz rzadziej - W-E. Większość stwierdzonych uskoków przemieszcza zarówno utwory mezozoiczne i mioceńskie jak i czwartorzędowe, co świadczy o ich współczesnej aktywności. W pokrywających dużą część terenu czwartorzędowych koluwiach zaznaczają się kierunki niemal wszystkich uskoków stwierdzonych w utworach mezozoicznych. Współczesna aktywność uskoków spowodowała utworzenie się na powierzchni terenu wyraźnych pierwotnych skarp uskokowych, które nie uległy dotychczas procesom denudacyjnym.
EN
Fault/fracture network within Mesozoic and Quaternary formations has been studied in Rio Colca Valley in Pinchollo - Lari - Maca area (Peruvian Andes). The results show structural framework of the Rio Colca Valley based on nearly all tectonic discontinuities observed in the area; mostly on WNW-ESE and NE-SW faults, and on few W-E faults. Displacements of Mesozoic, Miocene and Quaternary formations observed on nearly all faults in the study area provide evidence for recent tectonic activity. Most of the faults in the Mesozoic bedrock continue in Quaternary colluvial deposits. Recent faulting led to development of a system of distinct, primary scarps and land cracks on the surface, which have not been eroded yet.
PL
Dla utworów paleozoicznych i mezozoicznych z otworów Polskie Łąki PIG 1 oraz Toruń 1 (strefa Koszalin–Chojnice, pomorski segment szwu transeuropejskiego) przeprowadzono analizę strukturalną. Badania te miały na celu określenie charakteru struktur tektonicznych, wydzielenie ich generacji, ustalenie sekwencji zdarzeń tektonicznych oraz odtworzenie warunków i charakteru deformacji. Budowa strukturalna utworów paleozoicznych w analizowanych profilach ze strefy Koszalin–Chojnice została ukształtowana wskutek wielofazowych deformacji, zachodzących głównie w reżimie kontrakcyjnym i transpresyjnym. Mniejszy wpływ wywołały deformacje zachodzące w warunkach przesuwczych, ekstensyjnych oraz transtensyjnych. Najstarsze rozpoznane epizody deformacji tektonicznych były związane z reżimem kontrakcyjnym (nasuwczym) oraz przesuwczym. Powstały wówczas makro- i mezofałdy ze zginania F1 oraz złupkowanie o charakterze kliważu S1, złupkowanie S2 i poziome mezofałdy F2 oraz złupkowanie S3 oraz pionowe lub stromo nachylone mezofałdy F3. Utwory zaangażowane przez te deformacje cechuje budowa fałdowa oraz fałdowo-nasunięciowa, duże upady tektoniczne i w efekcie istotna niezgodność kątowa na kontakcie z utworami wyżej leżącymi, które ponadto są wyraźnie słabiej zdiagenezowane niż kompleks objęty deformacjami D1–D3. Deformacje tego etapu można wiązać z kaledońską kolizją Awalonii i Baltiki oraz tektonicznym oddziaływaniem tworzącego się orogenu na swoje przedpole. Lewoskrętna składowa przesuwcza ówczesnych deformacji stanowi najprawdopodobniej odzwierciedlenie skośnego charakteru tej kolizji. Deformacje te zachodziły przypuszczalnie we wczesnym sylurze (landowerze). Deformacje tektoniczne z pogranicza syluru i dewonu miały prawdopodobnie mniejszą rangę niż deformacje śródsylurskie. Kolejne, młodsze epizody aktywności tektonicznej doprowadziły do powstania deformacji o bardzo zmiennym charakterze, od ekstensyjnych, przez transtensyjne, transpresyjne, do nasuwczych. Deformacje te przypuszczalnie wiążą się z waryscyjskim i powaryscyjskim (przedpóźnopermskim) etapem ewolucji obszaru badań, zwłaszcza z późnokarbońsko-wczesnopermskim wynoszeniem tektonicznym i tektoniką blokową. Powstały wówczas najstarsze żyłki węglanowe, struktury fałdowe F4, tj. fałdy szerokopromienne oraz wergentne fałdy ciągnione i pasożytnicze o poziomo leżących lub nieco nachylonych osiach, strefy mylonityzacji oraz brekcji tektonicznych, uskoki progowo-prawoprzesuwczo-zrzutowe, a także szerokopromienne, leżące struktury fałdowe F5. Ponadto na tym etapie deformacji lokalnie powstawały kakiryty i kataklazyty oraz, rzadziej, mylonity. Następny z głównych etapów deformacji w strefie Koszalin–Chojnice obejmował kilka epizodów związanych z reżimem ekstensyjnym (transtensyjnym?) oraz transpresyjnym. Deformacje tego etapu zachodziły zapewne w okresie od późnego triasu do pogranicza kredy i paleogenu. Interpretować je można jako odzwierciedlenie rozwoju transtensyjnych rowów tektonicznych w późnym triasie–wczesnej jurze, w mniejszym stopniu również w środkowej jurze i wczesnej kredzie, a następnie ich inwersji tektonicznej w późnej kredzie oraz na pograniczu kredy i paleogenu. Na tym etapie deformacji dochodziło do przemieszczeń normalno-zrzutowych i normalno-prawoprzesuwczych, rozwoju żył wypełnionych węglanami, a także przemieszczeń przesuwczych i przesuwczo-nasuwczych.
EN
The recent tectonic structure of the Palaeozoic and Mesozoic successions observed in the Polskie Łaki PIG 1 and Toruń 1 boreholes (the Koszalin-Chojnice zone) was formed as a result of multiphase deformations, related mainly to contractional and transpressional regime, while impact of tectonic processes related to extensional and transtensional regime was less pronounced. The oldest, recognized episodes of deformation were associated with contractional and strike-slip tectonic activity. This led to development of bending-related macro-and mesofolds F1 and cleavage S1, schistosity S2 and recumbent mesofolds F2, as well as schistosity S3 and vertical or steeply dipping mesofolds F3. Sediments involved in this deformation are generally characterized by fold and thrust tectonic style, steep tectonic dipping causing significant angular unconformity with the overlying successions. The latter are also much less affected by diagenesis as compared with successions involved in deformation D1-D3. These deformations could be related to the Caledonian collision of Avalonia and Baltica and to an impact of developing orogen onto tectonic regime of its foreland. Left-lateral component of the deformation D1-D3 probably reflects oblique character of the collision. The deformation D1-D3 developed presumably during the Early Silurian time (Llandovery). Tectonic activity at the end of Silurian-beginning of Devonian was probably of the lesser importance than intra-Silurian one. The following, younger episodes of tectonic activity led to development of deformation revealing very changeable tectonic regime, from extensional and transtensional to transpressional and compressional. This generation of deformations was probably related to Variscan and post-Variscan (pre-late Permian) stage of evolution of the study area, in particular with the late Carboniferous-early Permian significant uplift and fault block tectonics. This stage of deformation led to development of calcite veins, fold structures F4, i.e. broad folds as well as dragged and parasitic folds with lateral or sub-lateral fold axes, zones of mylonitzation and tectonic breccias, sub-vertical normal faults with right-lateral strike-slip component, and broad recumbent folds F5. Moreover, kakirites, cataclasites and, less common, mylonites locally developed at this stage. The next of the main stages of deformation in the Koszalin-Chojnice zone encompassed several episodes related to extensional (transtesional?) and transpressional tectonic regime. This deformation developed probably during the Late Triassic to the late-most Cretaceous-earlymost Cainozoic. The deformation are interpreted as an expression of development of transtensional tectonic grabens in the Late Triassic-Early Jurassic and, to a lesser degree, in the Middle Jurassic and Early Cretaceous, as well as of their subsequent tectonic inversion in the Late Cretaceous and the latemost Cretaceous-earlymost Cainozoic time. This stage of deformation is characterized by development of normal faults, often with right-lateral strike component, calcite veins as well as strike-slip faults and thrust with strike-slip component.
PL
Wzdłuż strefy tektonicznej Kraków-Lubliniec tworzącej kontakt pomiędzy blokami małopolskim i górnośląskim stwierdzono występowanie licznych przejawów magmatyzmu, w rejonie Myszkowa, Zawiercia, Pilicy, Doliny Będkowskiej i Koziegłów (Mysłowa) oraz Żarek. Powstanie intruzji granitoidów łączy się z wielofazową ewolucją strukturalną tej strefy, której szczególnie duża aktywność zaznaczyła się pod koniec syluru i w karbonie górnym. Mineralizacja kruszcowa występuje zarówno w skałach magmowych jak i w zmetamorfizowanych skałach osłony (wendyjskich i paleozoicznych). Skały magmowe to genetycznie różnorodna asocjacja skał intruzywnych: granitoidów (głównie granodiorytów, rzadziej granitów), porfirów (dacytów), dolerytów (diabazów) i gabr. Przeobrażenia o charakterze metamorfizmu regionalnego (facja zieleńcowa) zaznaczyły się tylko w utworach kompleksu wendyjskiego, natomiast metamorfizm termiczny i termiczno-metasomatyczny, będący efektem oddziaływania granitoidowych intruzji na skały otaczające, obejmuje utwory: wendu, ordowiku, syluru i dewonu. Okruszcowanie skał wykazuje ścisły związek z oddziaływaniem wysoko stężonych solanek zasobnych w metale, powiązanych genetycznie z kwaśnym magmatyzmem. Pierwiastkami wskaźnikowymi, które mogą mieć znaczenie prognostyczne przy poszukiwaniu zakrytych złóż porfirowych w innych obszarach tego rejonu, są: W, Mo, Cu, Ag, K, F, Sb, Hg, Au, Pb, Ba, As, Zn, Bi i Te.
EN
Numerous occurrences of magmatism are observed in the vicinity of Myszków, Zawiercie, Pilica, Będkowska Valley, Koziegłowy (Mysłów) and Żarki along the Kraków-Lubliniec tectonic zone which is a contact zone of the Małopolska and Upper Silesia blocks. The formation of granitoid intrusion is related to a multiphase structural evolution of the zone whose especially intensive activity took place at the end of the Silurian and Upper Carboniferous. Ore mineralization occurs both in igneous and metamorphic wall rocks (Vendian, Palaeozoic). Igneous rocks consist of a genetically different association of intrusive rocks: granitoids (mainly granodiorites, rare granites), dacites, dolerites (diabases) and gabbros. Alterations, which show regional metamorphic nature (greenschist facies), were recorded only in the Vendian complex formations, while thermal and thermal -metasomatic metamorphism, being the effect of influence of granitoid intrusion into wall rocks, affected Vendian, Ordovician, Silurian and Devonian formations. Ore contents of the rocks show direct relationship with highly concentrated metal-rich salinewaters, closely related to acid magmatism. W, Mo, Cu, Ag, K, F, Sb, Hg, Au, Pb, Ba, As, Zn, Bi and Te are elements-pathfinders which can be applied to searching for covered porphyry deposits in other parts of the region.
19
Content available remote Promieniotwórczość naturalna wybranych skał krystalicznych bloku izerskiego
EN
Results of natural radioactivity of 40K, 208Tl, 212Pb, 212Bi, 214Pb, 214Bi, 228Ac and the fallout of 137Cs measured in situ in typical crystalline (both igne-ous and metamorphic) rocks of the Izera Block (Sudetes Mountains, southwestern Poland) using a portable gamma-ray spectrometry workstation are presented. The highest activity concentrations of 40K and 226Ra (238U series) were noted in laminated gneisses whereas the highest activity concentration of 228Ac (232Th series) is characteristic for Sn-bearing mica schists. The lowest activity concentrations of 40K, 228Ac and 226Ra refer to the basalts, flaser gneisses and Izera granites, respectively. The measurements carried out in the study area have shown relatively low level of 137Cs fall-out.
20
Content available remote Wulkan Kilimandżaro - geoturystyczna atrakcja Afryki
PL
Wulkaniczny masyw Kilimandżaro stanowi największą wyniosłość Afryki (5895 m n.p.m.), a zarazem jest najwyższą, samotnie stojącą górą Ziemi. Kilimandżaro leży na wschodnim obrzeżu ryftu Gregory'ego, stanowiącego wschodni segment wschodnioafrykańskiego systemu ryftowego (East African Rift System). Ewolucja tego systemu przebiega od miocenu do dziś. Wulkan Kilimandżaro ukształtował się (w warunkach tektoniki ekstensyjnej) w plejstocenie. Stanowi on produkt wulkanizmu alkalicznego; jest zbudowany głównie z trachitów, fonolitów, bazaltów i lokalnie nefelinitów, a także odpowiadających im skał piroklastycznych. Ze względu na unikalne walory przyrodnicze i turystyczne na terenie tym powstał w 1973 roku Park Narodowy Kilimandżaro obejmujący obszar 756 km kwadratowych, położony powyżej 2700 m n.p.m. Rejon ten został też wpisany na Listę Światowego Dziedzictwa Kulturalnego i Przyrodniczego UNESCO.
EN
The Kilimanjaro volcanic massif is the tallest mountain in Africa (5,895 meters a.s.l.) and, simultaneously, is the tallest single mountain on the Earth. Kilimanjaro is located at the eastern margin of Gregory rift, which is the eastern segment of the East African Rift System. Evolution of this system has commenced in Miocene and continues until Recent. The Kilimanjaro volcano formed in Pleistocene, under the conditions of extensional regime and is a product of alkaline volcanism. The mountain is formed by trachytes, phonolites, basalts and local nephelinites with corresponding pyroclastics. Due to unique, natural and touristic values of the area the Kilimanjaro National Park has been established in 1973. The park covers the area of 756 square kilometers of terrain over the altitude of 2,700 meters a.s.l. The area was included into the UNESCO World Cultural and Natural Heritage List.
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