Small angle X-ray scattering mapping and kinetics study of sub-critical CO2 sorption by two Australian coals     

Andrzej P. Radliński  Tara L. Busbridge  Evan Mac A. Gray  Tomasz P. Blach  David J. Cookson 《International Journal of Coal Geology》2009,77(1-2):80-89

Time- and position-resolved synchrotron small angle X-ray scattering data were acquired from samples of two Australian coal seams: Bulli seam (Bulli 4, R_o = 1.42%, Sydney Basin), which naturally contains CO₂ and Baralaba seam (R_o = 0.67%, Bowen Basin), a potential candidate for sequestering CO₂. This experimental approach has provided unique, pore-size-specific insights into the kinetics of CO₂ sorption in the micro- and small mesopores (diameter 5 to 175 Å) and the density of the sorbed CO₂ at reservoir-like conditions of temperature and hydrostatic pressure.For both samples, at pressures above 5 bar, the density of CO₂ confined in pores was found to be uniform, with no densification in near-wall regions. In the Bulli 4 sample, CO₂ first flooded the slit pores between polyaromatic sheets. In the pore-size range analysed, the confined CO₂ density was close to that of the free CO₂. The kinetics data are too noisy for reliable quantitative analysis, but qualitatively indicate faster kinetics in mineral-matter-rich regions.In the Baralaba sample, CO₂ preferentially invaded the smallest micropores and the confined CO₂ density was up to five times that of the free CO₂. Faster CO₂ sorption kinetics was found to be correlated with higher mineral matter content but, the mineral-matter-rich regions had lower-density CO₂ confined in their pores. Remarkably, the kinetics was pore-size dependent, being faster for smaller pores.These results suggest that injection into the permeable section of an interbedded coal-clastic sequence could provide a viable combination of reasonable injectivity and high sorption capacity.  相似文献   

VSP polarization angles determination: Wysin-1 processing case study     

Mateusz Zaręba  Tomasz Danek 《Acta Geophysica》2018,66(5):1047-1062

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High-resolution computed microtomography for the characterization of a diffusion tensor imaging phantom     

Łukasz Kaczmarek  Tomasz Wejrzanowski  Jakub Skibiński  Michał Maksimczuk  Artur Krzyżak 《Acta Geophysica》2017,65(1):259-268

This paper addresses the issue of the quantitative characterization of the structure of the calibration model (phantom) for b-matrix spatial distribution diffusion tensor imaging (BSD-DTI) scanners. The aim of this study was to verify manufacturing assumptions of the structure of materials, since phantoms are used for BSD-DTI calibration directly after manufacturing. Visualization of the phantoms’ structure was achieved through optical microscopy and high-resolution computed microtomography (µCT). Using µCT images, a numerical model of the materials structure was developed for further quantitative analysis. 3D image characterization was performed to determine crucial structural parameters of the phantom: porosity, uniformity and distribution of equivalent diameter of capillary bundles. Additionally calculations of hypothetical flow streamlines were also performed based on the numerical model that was developed. The results obtained in this study can be used in the calibration of DTI-BST measurements. However, it was found that the structure of the phantom exhibits flaws and discrepancies from the assumed geometry which might affect BSD-DTI calibration.  相似文献   

Sediment detachment in piping-prone soils: Cohesion sources and potential weakening mechanisms     

Anita Bernatek-Jakiel  Jiří Bruthans  Jan Vojtíšek  Mateusz Stolarczyk  Tomasz Zaleski 《地球表面变化过程与地形》2020,45(13):3185-3201

Soil piping is a widespread land degradation process that may lead to gully formation. However, the processes involved in sediment detachment from soil pipe walls have not been well studied, although their recognition is a crucial step to protect soils from piping erosion. This study aims to recognize the factors affecting cohesion and to identify the mechanisms which are likely to be responsible for the disintegration of soil. The study has been conducted in mid-altitude mountains under a temperate climate (the Bieszczady Mountains, the Carpathians, SE Poland). The research was based on the detailed field and laboratory analyses of morphology, and the physical and chemical properties of soil profiles with and without soil pipes. Moreover, experiments with flooding the undisturbed soil samples using different solutions (deionized water, ammonium oxalate, dithionate citrate, 35% hydrochloric acid and 30% hydrogen peroxide) were conducted in order to check the role of air slaking, the removal of soil organic carbon (SOC), and Fe and Al oxides on sediment detachment. The obtained results have confirmed that soil pipes develop in quite cohesive soils (silt loams), which allow the formation and maintenance of pipes with a diameter up to 30 cm. Soil cohesion, and thus susceptibility to piping, are impacted by the content of major oxides, soil particle size distribution, biological activity and porosity. The tested soils affected by piping erosion have a lower content of Al₂O₃ and Fe₂O₃, and free Fe (Fe_(DCB)), lower clay content, higher biological activity (more roots and animal burrows), higher porosity, and more and larger pores than the profile without soil pipes. The experiments have indicated that especially SOC along with Fe and Al oxides are an important cohesion source in the study area. This suggests that the removal of SOC, and Fe and Al oxides may weaken and disintegrate aggregates in soil pipes. Further study of soil leaching and tensile strength will broaden understanding of which chemical processes control where pipes will develop in other cohesive piping-prone soils. © 2020 John Wiley & Sons, Ltd.  相似文献   

Origin and post-glacial evolution of surface cracks: A case study from the area of the Last Glaciation,north-eastern Poland     

Tomasz Karasiewicz  Anna Hrynowiecka  Piotr Weckwerth  Lucyna Tobojko  Dominik Pawłowski  Wojciech Wysota  Arkadiusz Krawiec  Michał Dąbrowski 《地球表面变化过程与地形》2024,49(2):525-548

The analysis of LiDAR-based digital elevation models revealed the existence of groups of longitudinal fractures in the ground in northern Poland at the limit of the ice sheet's extent during its last maximum. Our research on the closed elongated depressions (CEDs) of the Jedwabno test field (Szuć site, north-east Poland) focuses on explaining their origins and their post-glacial history. This region was covered by an ice sheet and glacitectonically active during the Vistulian, and at least some surface fractures are possible witnesses to this activity. Using geomorphological mapping, sedimentological and geophysical research, we assumed it was related that the origin of these features here is associated with groundwater migration at the end of the Vistulian glaciation or later when groundwater flow intensified due to a rapid climate warming that caused permafrost to melt. The thawing of permafrost caused to transition from continuous permafrost to discontinuous, which in turn created groundwater flow that was probably responsible for the development of the surface cracks (fractures). Radiocarbon, palaeobiological (pollen, Cladocera) and geochemical studies allowed for an estimation of the formation time of these unique surface cracks in the Older Dryas. Prevailing conditions were also reconstructed for the later dynamic changes of the end of the Late Vistulian glaciation and in the Late Holocene until the Subatlantic Period (Megalayan stage). The surface cracks with steep slopes, despite their small area, are extraordinary sedimentation traps that have, in a special way, retained an almost complete record of the environmental and climate changes of the Late Glacial. There are sedimentological gaps in the Holocene, especially after the Preboreal (old part of the Greenlandian Stage), caused by changes in water levels, aeolian processes and human activity.  相似文献   

Predicting juvenile Baltic cod (Gadus morhua) age from body and otolith size measurements     

Fey  Dariusz P.; Linkowski  Tomasz B. 《ICES Journal of Marine Science》2006,63(6):1045-1052

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Remnants of altered meteorite in the Cretaceous‐Paleogene clay boundary in Poland          下载免费PDF全文

Krzysztof Szopa  Tomasz Brachaniec  Łukasz Karwowski  Tomasz Krzykawski 《Meteoritics & planetary science》2017,52(4):612-622

Fossil iron meteorites are extremely rare in the geological sedimentary record. The paleometeorite described here is the first such finding at the Cretaceous‐Paleogene (K‐Pg) boundary. In the boundary clay from the outcrop at the Lechówka quarry (Poland), fragments of the paleometeorite were found in the bottom part of the host layer. The fragments of meteorite (2–6 mm in size) and meteoritic dust are metallic‐gray in color and have a total weight of 1.8181 g. Geochemical and petrographic analyses of the meteorite from Lechówka reveal the presence of Ni‐rich minerals with a total Ni amount of 2–3 wt%. The identified minerals are taenite, kamacite, schreibersite, Ni‐rich magnetite, and Ni‐rich goethite. No relicts of silicates or chromites were found. The investigated paleometeorite apparently represents an independent fall and does not seem to be derived from the K‐Pg impactor. The high degree of weathering did not permit the chemical classification of the meteorite fragments. However, the recognized mineral inventory, lack of silicates, and their pseudomorphs and texture may indicate that the meteorite remains were an iron meteorite.  相似文献   

Desiccation shrinkage of non‐clayey soils: a numerical study     

Liang Bo Hu  Hervé Péron  Tomasz Hueckel  Lyesse Laloui 《国际地质力学数值与分析法杂志》2013,37(12):1782-1800

A mesoscale model of desiccation of soil based on the evolution of the pore system idealized as bimodal is numerically examined. A simplified evolution of the model reveals a series of characteristics that qualitatively agree with the observed macroscopic experimental findings. The principal mechanism is deemed to be driven by the surface evaporation and water outflow generating a pore pressure gradient resulting in the shrinkage mainly of the largest pores. The amount of shrinkage is a function of (negative) pore pressure and is controlled by the compressibility of the solid matrix. The numerical model includes also the ensuing partial saturation stage initiated by the air entry simulated as a scenario with a moving phase interface inside the pore. The proposed model can be extended beyond the two‐mode porosity soils, to include the multi‐modal porosity, or its statistical representation.Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Forecasting sea level anomalies from TOPEX/Poseidon and Jason-1 satellite altimetry     

Tomasz Niedzielski  Wiesław Kosek 《Journal of Geodesy》2009,83(5):469-476

This paper aims at the prediction of both global mean sea level anomalies (SLAs) and gridded SLA data in the east equatorial Pacific obtained from TOPEX/Poseidon and Jason-1 altimetric measurements. The first prediction technique (denoted as LS) is based on the extrapolation of a polynomial-harmonic deterministic least-squares model describing a linear trend, annual and semi-annual oscillations. The second prediction method (denoted as LS + AR) is a combination of the extrapolation of a polynomial-harmonic model with the autoregressive forecast of LS residuals. In the case of forecasting global mean SLA data, both techniques allow one to compute the predictions of comparable accuracy (root mean square error for 1-month in the future is of 0.5 cm). In the case of predicting gridded SLA data, the LS + AR prediction method gains significantly better prediction accuracy than the accuracy obtained by the LS technique during El Niño 1997/1998, La Niña 1998/1999 and during normal conditions.  相似文献   

Climate change during the past 1000 years: a high‐temporal‐resolution multiproxy record from a mire in northern Finland     

Walter Finsinger  Kristian Schoning  Sheila Hicks  Andreas Lücke  Tomasz Goslar  Friederike Wagner‐cremer  Heidi Hyyppä 《第四纪科学杂志》2013,28(2):152-164

We present a record of peatland development in relation to climate changes and human activities from the Palomaa mire, a remote site in northern Finland. We used fine‐resolution and continuous sampling to analyse several proxies including pollen (for vegetation on and around the mire), testate amoebae (TA; for mire‐wetness changes), oxygen and carbon isotopes from Sphagnum cellulose (δ¹⁸O and δ¹³C; for humidity and temperature changes), peat‐accumulation rates and peat‐colour changes. In spite of an excellent accumulation model (30 ¹⁴C dates and estimated standard deviation of sample ages <1 year in the most recent part), the potential to determine cause–effect (or lead–lag) relationships between environmental changes and biotic responses is limited by proxy‐specific incorporation processes below the actively growing Sphagnum surface. Nevertheless, what emerges is that mire development was closely related to water‐table changes rather than to summer temperature and that water‐table decreases were associated with increasing peat‐accumulation rates and more abundant mire vegetation. A rapid fen‐to‐bog transition occurred within a few years around AD 1960 when the water table decreased beyond the historical minimum, supporting the notion that mires can rapidly shift into bogs in response to allogenic factors. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献