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1

Influence of liquid-nitrogen freezing of gas-bearing shale rocks on their compressive strength

Borek K.

Mineralogia

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2018

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Vol. 49, iss. 1/4

7--16

EN

Any definable relation between falling temperature and the compressive strength of shale rocks should provide a useful predictive tool aiding optimization of the results of hydraulic fracturing. In this research, an automeasuring hydraulic press, a thermo-camera and the Fluent ANSYS software were used. The results of laboratory simulations, and the effects of experiments conducted on shale rocks to determine permanent changes in compressive strength, are presented. As both frozen rocks and rocks returned to room temperature show diminished compressive strength. It is suggested that prior freezing of rocks can increase the efficiency of fracturing.

2

Lower Toarcian organic-rich sediments from the Tuscan Succession (Northern Apennines, Italy): preliminary results

Perilli N., Rodrigues R., Veiga de Oliveira L., Catanzariti R.

Volumina Jurassica

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2009

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Vol. 7, no. 1

55-65

EN

For the first time is here documented the presence of Lower Toarcian black shales in the lower portion of the Calcari e marne a Posidonia (Posidonia Marls auctt.) belonging to the Tuscan Nappe. It consists of alternations of 30 cm to 5 m thick black laminated marlstone and marly claystone, with TOC values ranging from 0.43% to 2.49%. Based on calcareous nannofossils, the basal portion of the Calcari e marne a Posidonia spans the Lotharingius hauffii to Carinolithus superbus zones, and the organic-rich interval lies within the Carinolithus superbus Zone.

3

Środowisko sedymentacji i wczesna diageneza czarnych łupków ogniwa Passhatten (środkowy trias, Spitsbergen, Svalbard) na podstawie analizy geochemicznej

Karcz P.

Przegląd Geologiczny

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2009

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Vol. 57, nr 10

918-926

EN

Geochemical analysis of the 50 samples of the Middle Triassic black shales (organic carbon-rich siltstones) has been carried out. The black shale samples (up to 4.92 % TOC) have been collected in the stratotype profile of the Bravaisberget Formation, west Spitsbergen. In the examined profile, the black shales occur exclusively in the Passhatten Member (the lower and middle interval of the Bravaisberget Formation). Black shale samples have been analyzed in respect to degree of pyritization (DOP), isotopic composition of pyrite sulphur (34S) and organic carbon content (TOC). The main goal of the research was to examine a degree of oxygenation and dynamics of a sea-bottom environment. DOPvalues from lower section of the Passhatten Member show wide variation, ranging from 0.29 to 0.92. In upper section of the member, the obtained DOPvalues show narrower range of variations, from 0.77 to 0.98.Wide variations of DOPwere caused by temporary coexistence of oxic and anoxic bottom currents. In turn, narrow DOP variations indicate predominance of stratified water and anoxic bottom currents. DOP/34S and DOP/TOC ratios imply that syngenetic and early diagenetic pyrite precipitation during accumulation of the lower section of the Passhatten Member was controlled by availability of organic carbon and reactive iron, whereas accumulation of the member's upper section was controlled exclusively by availability of reactive iron.

4

Ammonia pressure leaching for Lubin shale middlings

Chmielewski T., Wódka J., Iwachów Ł.

Physicochemical Problems of Mineral Processing

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2009

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Vol. 43

5-20

EN

Ammonia pressure leaching has been investigated as an alternative for hydrometallurgical processing of Lubin middlings - a shale%enriched flotation by%product. The effect of primary parameters: temperature, oxygen partial pressure, ammonia and ammonium sulfate concentration and stirring rate on leaching recovery of Cu, Ag, Zn, Ni, and Co were examined.

PL

Badano proces ciśnieniowego ługowania amoniakalnego półproduktu flotacji z ZWR Lubin, wzbogaconego we frakcję łupkową. Ługowanie amoniakalne analizowano jako alternatywny sposób hydrometalurgicznego przetwarzania tego półproduktu. Badano wpływ najważniejszych parametrów: temperatury, ciśnienia parcjalnego tlenu, stężenia amoniaku i siarczanu amonowego oraz szybkości mieszania na szybkość ługowania Cu, Ag, Zn, Ni i Co.

5

Middle Jurassic black shales (Skrzypny Shale Formation) - palaeoenvironmental significance of one of the oldest deposits of the Pieniny Klippen Belt

Górniak K., Bahranowski K., Gaweł A., Marynowski L., Szydłak T.

Geoturystyka

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2008

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nr 2

19-24

EN

This paper deals with a fragment of geological history of Middle Jurassic black spherosideritic shales outcropping in upper part of the Homole Gorge (Skrzypny Shale Formation, Niedzica succession). These important deposits belong to the Flackenmergel facies, widespread in oceanic Tethyan deposits. This formation represents one of the oldest rocks of the Pieniny Klippen Belt. Dark colour of these rocks (total organic carbon content in them amounts to about 1 wt.%) and the occurrence of siderite concretions indicate reducing conditions of their origin but oxidizing environment of waters above them in sedimentary basin. Oxic conditions of organic matter sedimentation are confirmed by the elevated values of pristine to phytane ratio. Moreover the results based on n-alkanes indicate mixed terrestrial/marine origin of organic matter with prevalence of the last one. These information are slightly obliterated because of advanced thermal maturity of organic matter caused by post-sedimentation processes. Microstructural features of deposits of the Skrzypny Shale Formation and the composition of clay minerals occurring in them indicate late diagenetic conditions. In SEM images we observe one-directional orientation of clay minerals and rotation of mica flakes, often chloritized. Clay minerals are represented by high-illitic illite/smectite, micas, post-biotitic chlorite and subordinately kaolinite. As follows from authors studies, these macroscopically nearly "mute" clay rocks, little interesting in outcrops, particularly when they occur in such attractive geological objects as the Homole Gorge, can be the source of important information concerning the history of sedimentation basins.

PL

Praca przedstawia fragment historii geologicznej środkowojurajskich czarnych łupków sferosyderytowych ukazujących się w niewielkim odsłonięciu w górnej części wąwozu Homole (formacja lupków ze Skrzypnego, sukcesja niedzicka). Te ważne utwory należą do facji Fleckenmergiel szeroko rozpowszechnionej w oceanie Tetydy. Formacja łupków ze Skrzypnego reprezentuje jedne z najstarszych skał pienińskiego pasa skałkowego. Ciemna barwa badanych skał (zawartość całkowitego węgla organicznego około 1% wag.) oraz występowanie w nich konkrecji syderytowych, wskazują na warunki redukcyjne panujące w osadzie, natomiast na obecność natlenionych wód nad osadem w środowisku ich sedymentacji. Sedymentację substancji organicznej w warunkach raczej utleniających potwierdzają badania związków organicznych, tj. wysokie wartości stosunku pristan/fitan. Wyniki tych badań wskazują ponadto na mieszane, lądowo/morskie pochodzenie substancji organicznej z przewagą ostatniej z wymienionych. Informacje te są nieco zatarte z powodu dużej dojrzałości termicznej substancji organicznej spowodowanej procesami postsedymentacyjnymi. Cechy mikrostrukturalne utworów formacji łupków ze Skrzypnego oraz skład występujących w nich minerałów ilastych wskazują na warunki odpowiadające późnej diagenezie. W obrazach elektronomikroskopowych (SEM) widoczna jest bowiem jednokierunkowa orientacja minerałów ilastych i rotacja blaszek mik, często schlorytyzowanych. W składzie minerałów ilastych występuje zaś wysokoillitowy illit/smektyt, miki, pobiotytowy chloryt i podrzędnie kaolinit. Z przeprowadzonych badań wynika, że makroskopowo niemal "nieme" skały ilaste, niepozorne wyglądające w odsłonięciu, szczególnie jeśli występują obok atrakcyjnych obiektów geologicznych jak to ma miejsce w wąwozie Homole, są źródłem ważnych informacji dotyczących historii basenów sedymentacyjnych. Warto więc zwrócić na nie uwagę.

6

Geological history of the Pieniny Klippen Belt and Middle Jurassic black shales as one of the oldest deposits of this region - stratigraphical position and palaeoenvironmental significance

Krobicki M., Golonka J.

Geoturystyka

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2008

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nr 2

3-18

EN

The main aim of this paper is presentation both general history of the Pieniny Klippen Belt and two famous sites in this region: Dunajec River Gorge and Homole Gorge. According to such general introduction the authors explain also palaeogeographical position of the Pieniny Klippen Belt Basin within Mesozoic Tethyan Ocean, and especially stratigraphical position and palaeoenvironmental conditions of Middle Jurassic black shales and their significance in geodynamic reconstruction of this basin. Both the Dunajec River Gorge, one of the most popular geotouristic object within Pieniny Mts. and Homole Gorge, one of the best place to geological study of the Pieniny Klippen Belt, are most attractive natural phenomena of this geological region.

PL

Głównym celem niniejszej pracy jest prezentacja zarówno generalnej historii pienińskiego pasa skałkowego jak i dwóch słynnych miejsc tego regionu: przełomu Dunajca i wąwozu Homole. W nawiązaniu do takiego generalnego wprowadzenia autorzy przedstawiają również paleogeograficzną pozycję basenu pienińskiego pasa skałkowego w obrębie mezozoicznego oceanu Tetydy, a szczególnie stratygraficzną pozycję i paleośrodowiskowe warunki powstawania środkowojurajskich czarnych łupków oraz ich znaczenie w geodynamicznych rekonstrukcjach tego basenu. Zarówno spływ Dunajcem, jeden z najbardziej popularnych obiektów geoturystycznych w Pieninach, jak i wąwóz Homole, jedno z najlepszych miejsc do studiowania geologii pienińskiej, są najbardziej atrakcyjnymi obiektami przyrodniczymi w tym regionie geologicznym.

7

Sedimentary environments of the Middle Jurassic epicontinental deposits from the central part of the Polish Basin (Kuiavian Region)

Feldman-Olszewska A.

Volumina Jurassica

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2006

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Vol. 4, no. 1

86-86

EN

The Polish Basin was the eastern part of the Jurassic European epicontinental basin. The zone of maximum thickness of the Middle Jurassic deposits runs along the so called Mid-Polish Trough which extends from the West Pomerania (NW) to the Holy Cross Mountains (SE), generally along the Teisseyre-Tornquist Zone. The complete litological profile of the Middle Jurassic deposits exceeds 1100 m in the depocentre of the Mid-Polish Trough (in the Kuiavian Region). Sediments are represented by sandstones, mudstones, heteroliths and claystones with intercalations of siderites, dolomites and coquina beds. Subordinately, crinoidal limestones, arenaceous limestones, gaizes and oolitic ironstones occur. Sedimentological studies were based on investigation of cores from ten deep boreholes. Nineteen lithofacies were distinguished: black shales, massive mudstones, bioturbated mudstones, lenticular bedded mudstones, heteroliths, wavy bedded sandstones, flaser bedded sandstones, sandstones with clay drapes, structureless sandstones (massive and bioturbated), parallel bedded sandstones, cross bedded sandstones, HCS (hummocky cross stratification) cross bedded sandstones, ripple bedded sandstones, herringbone cross bedded sandstones, chamosite sandstones, calcareous sandstones and arenaceous limestones, crinoidal limestones, conglomerates, condensed bed. Additionally, 15 ichnogenera of trace fossils: Asterosoma isp., Bergaueria isp., Chondrites isp., Diplocraterion isp., Gyrochorte isp., Lockeia isp., Ophiomorpha isp., Palaeophycus isp., Planolites isp., Rosselia isp., Skolithos isp., (?)Spongeliomorpha isp., Teichichnus isp., Terebellina isp. and Thalassinoides isp. were recognized in the Middle Jurassic deposits of Kuiavian Region. They point to sedimentation in the transition zone - foreshore environments. Based on the geochemical and palaeoecological investigations, four biofacies connected with different oxygenation of the bottom waters during sedimentation of the black shales have been proposed. The Upper Aalenian - Lower Bajocian deposits represent clayey sedimentation which occurred in dysoxic to anoxic environment. On the other hand, the Upper Bajocian - Lower Bathonian deposits represent dysoxic to oxic conditions. Sedimentation of the Middle Jurassic deposits in the central part of the Polish Basin took place in the shallow epicontinental sea, in environment spanning offshore to foreshore zones of a shallow siliciclastic shelf. Precise sedimentological studies point that the Middle Jurassic succession can be divided into 8 transgressive-regressive cycles. The oldest (Lower Aalenian) one begins with estuarine/foreshore sediments, sharply covered with offshore black shale facies. The Upper Aalenian, Bajocian and Lower Bathonian cycles are built of the transgressive offshore black shales and progradational regressive successions composed of mudstones and heteroliths and topped by shallow or middle shoreface sandstones. The Middle and Upper Bathonian cycles begin with transition zone sediments or lower shoreface deposits. The uppermost part of these cycles are built of sandstones and limestones representing the upper shoreface, foreshore and lagoon environments. The transgressive part of the last (Callovian) cycle is documented by carbonate-siliciclastic shoreface deposits which pass upwards into limestones of the Upper Jurassic. At the boundary between the Middle and the Upper Jurassic a condensed bed occurs.

8

Organic carbon accumulation events in the mid-Cretaceous rocks of the Pieniny Klippen Belt (Polish Carpathians) : a petrological and geochemical approach

Wójcik-Tabol P.

Geological Quarterly

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2006

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Vol. 50, No. 4

419-436

EN

New petrological and geochemical data lead to a consistent depositional model of the Corg.-rich sedimentation within the Pieniny Basin during themid-Cretaceous. Considerable terrestrial runoff into the Pieniny Basin occurred during the late Albian. Detritalmacerals accumulated under aerobic conditions on the shelf and continental slope. Fertilization of surface water induced primary productivity; aerobic degradation of organic matter led to the development of an oxygen-minimumzone within mid-water. The oxygen-minimumzone spread over almost all of the Pieniny Basin (Albian/Cenomanian). At the same time, a stagnant pool developed in the Grajcarek Basin. During the mid-Cenomanian the O2 minimum zone retracted and covered only the shelf and upper/middle slope. Stagnant pools might have formed in the depressions. Turbidity currents flowed down the slope and deposited calciturbiditic sequences with organic detritus in the Branisko and Pieniny basins. At the end of the Cenomanian, isolated anoxic or even H2S-bearing basins existed on the shelf. The slope was still occupied by the oxygen-minimum zone. In the deepest part of the sea-floor a stagnant basin formed.

9

The mid-Famennian ammonoid succession in the Rhenish Mountains: the "annulata Event" reconsidered

Korn D.

Geological Quarterly

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2004

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Vol. 48, No 3

245--252

EN

The mid-Late Devonian pelagic sedimentary successions of the Rhenish Mountains and other regions show a double black shale horizon called the annulata Black Shale. It marks, at the species level, a prominent faunal turnover of ammonoids from the Prolobites delphinus Zone into the Platyclymenia annulata Zone. An analysis of ammonoid genera distribution, phylogenetic relationships, andmorphospace occupation demonstrates that the "annulata Event" does not correspond to a crisis of the group and does not fulfill the criteria of a major biotic event.

10

Late Devonian facies variety in Iran: volcanism as a possible trigger of the environmental perturbation near the Frasnian-Famennian boundary

Mahmudy Gharaie M. H., Matsumoto R., Kakuwa Y., Milroy P. G.

Geological Quarterly

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2004

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Vol. 48, No 4

323-332

EN

Upper Devonian successions surrounding the Frasnian-Famennian (F-F) boundary in Iran consist of mixed carbonate/silisiclastic deposits. The successions are characterized by conspicuous ferruginous limestones, clay-rich units, black shales, and mafic volcanic rocks that provide important insights into palaeoenvironmental conditions during this interval of Earth’s history. An increase of kaolinite/illite ratio in clays associated with the F-F boundary suggests that increased chemical weathering was facilitated by warm and humid climatic conditions. Distinctive ferruginous-oolite deposits overlying the crucial Frasnian-Famennian boundary interval indicate a high supply rate of Fe-bearing clay originated during enhanced weathering under such climatic conditions. Black shales associated with the F-F boundary are interpreted to be the result of a high primary productivity caused by an increased influx of land-derived nutrients and regional volcanic activity. Widespread rift-related, basaltic activity along eastern Laurussia and northern Gondwana during the mid-Late Devonian is believed to have contribution to this global warming surrounding the F-F boundary.