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In this paper, we study the uncertainty quantification in inverse problems for flows in heterogeneous porous media. Reversible jump Markov chain Monte Carlo algorithms (MCMC) are used for hierarchical modeling of channelized permeability fields. Within each channel, the permeability is assumed to have a log-normal distribution. Uncertainty quantification in history matching is carried out hierarchically by constructing geologic facies boundaries as well as permeability fields within each facies using dynamic data such as production data. The search with Metropolis–Hastings algorithm results in very low acceptance rate, and consequently, the computations are CPU demanding. To speed-up the computations, we use a two-stage MCMC that utilizes upscaled models to screen the proposals. In our numerical results, we assume that the channels intersect the wells and the intersection locations are known. Our results show that the proposed algorithms are capable of capturing the channel boundaries and describe the permeability variations within the channels using dynamic production history at the wells. 相似文献
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K. Mallick 《Pure and Applied Geophysics》1971,87(1):102-110
Summary A harmonic steady-state analysis is dealt with for a layered earth with transition zone in the presence of an infinite cable carrying a.c. currents. Simplified relations are derived for the case when the transition zone rests directly on an infinitely resistive basement.Presently with the Bundesanstalt für Bodenforschung, Hannover (3 Hannover-Bucholtz, Alfred-Bentz-Haus, W-Germany) under the German Academic Exchanges Service programme. 相似文献
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In the vast alluvial plains of West Bengal and Orissa several deltaic plains exist, occurring in an off-lap sequence. These deltas were formed in the background of eustatic fluctuations during the Quaternary Period. They were built partly during rising sea level and pertly during stationary sea level stages. Landform analysis through aerial photographs as well as Landsat imagery interpretation, attested by field study, helped to establish the palaeogeomorphology of these Quaternary deltas. Possible mode of sedimentation during different phases of sea level fluctuations has been worked out 相似文献
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Dr. D. I. J. Mallick 《International Journal of Earth Sciences》1967,56(1):670-691
The Mpande gneiss dome consists of a core of gneiss and granite surrounded by stratified rocks of the Katanga System, including important acid and basic volcanics low in the sequence.Three phases of deformation are recognised, the first is characterised by large scale recumbent folds, the second by overturned folds and the third by microfolds. The metamorphism was monophase, maximum temperature being attained during the second phase and early part of the third phase of deformation. Maximum grade developed was of the staurolite zone in the pelites (staurolite-almandine subfacies of the amphibolite facies); sillimanite is absent. The decrease in temperature following the third phase of deformation involved static recrystallisation, but with little degradation of the high grade minerals.
Zusammenfassung Der Mpande-Gneis-Dom besteht aus einem Kern von Gneisen und Graniten, die von geschichteten Gesteinen des Katanga-Systems umgeben sind. Das Katanga-System enthält im wesentlichen saure und basische Vulkanite.Es wurden 3 Deformationsphasen festgestellt. Die erste ist charakterisiert durch großräumige, liegende Falten, die zweite durch überkippte Falten und die dritte durch Kleinfältelung. Die Metamorphose verlief einphasig, die höchsten Temperaturen wurden während der zweiten und zu Beginn der dritten tektonischen Deformationsphase erreicht. Die dabei auftretende Mineralparagenese entspricht in Peliten der Staurolith-Zone (Staurolith-Almandin-Subfazies der Amphibolith-Fazies); Sillimanit fehlt. Die Abnahme der Temperatur, die nach der dritten Deformationsphase folgt, ist mit einer statischen Rekristallisation verbunden, die die Hochtemperatur-Mineralien nur wenig erfaßt.
Résumé Le dôme de Mpande se compose d'un coeur de gneiss et de granite envellopé de rôches stratifiés du système de Katanga, y inclus d'importants volcaniques acides et basiques qui se trouvent dans la partie inférieure de la succession.Trois phases de déformation se voient; la première se caracterise par de grands plis couchés; la deuxième par des plis renversés, et la troisième par des microplis. Le metamorphisme fut monophase; la température maximum fut atteinte pendant la deuxième phase et au debut de la troisième phase de déformation. Le degré maximum était de la zone de staurotide dans les pélites (le sous-faciès de staurotide-almandine du faciès amphibolite), il manque de sillimanite. Le baissement de la témperature après la troisième phase de déformation apportait la recristallisation statique, mais avec peu de dégradation des minéraux de haut grade.
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Khan Nafis Sadik Roy Sujit Kumar Mazumder Md. Touhidur Rahman Talukdar Swapan Mallick Javed 《Natural Hazards》2022,114(1):883-906
Natural Hazards - The confluence of the Ganges, Jamuna, and Padma rivers is one of the most dynamic in the world, an internationally important research area because of the confluence of two of the... 相似文献
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Alqadhi Saeed Mallick Javed Talukdar Swapan Ahmed Mohd. Khan Roohul Abad Sarkar Showmitra Kumar Rahman Atiqur 《Natural Hazards》2022,111(1):641-660
Natural Hazards - Co-occurrence events of droughts and heatwaves characterized by abnormal low soil moisture (SM) and high temperatures may cause more significant impacts on society and natural... 相似文献
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Suryendu Dutta Sanket Bhattacharya Monalisa Mallick Ashish Chandra Shukla Ulrich Mann 《Journal of the Geological Society of India》2012,79(4):345-352
Lignite samples from Vastan and Tadkeshwar lignite mines, Cambay Basin have been analysed to elucidate lignin precursor using thermochemolysis-gas chromatography-mass spectrometry. The thermochemolysis products of lignites are characterized by monomethoxy-, dimethoxy-, and trimethoxybenzene derivatives originated from p-hydroxyphenyl, guaiacyl, and syringyl units of lignin polymer, respectively. The other compounds obtained in thermochemolysates of studied lignites are some resin derived C15 sesquiterpenoids, with a series of fatty acid methyl esters and n-alkanes/alkenes. The methylated guaiacyl and syringyl derivatives originate from the cleavage of β-O-4 linkages and subsequent methylation of acidic hydroxyl groups of preserved lignin. Gymnosperm lignin is characterized mainly by guaiacyl derivatives whereas angiosperm lignin yields some syringyl-type compounds in addition to guaiacyl-type compounds. By analogy with the lignin structure of modern trees, the abundant occurrences of syringyl derivatives in the thermochemolysis products of Surat lignites clearly demonstrate that the palaeofloral community was dominated by angiosperms during the deposition of these lignites. 相似文献
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A new space-domain operator based on the shape function concept of finite element analysis has been developed to derive the
residual maps of the Gorda Plate of western United States. The technique does not require explicit assumptions on isostatic
models. Besides delineating the Gorda Plate boundary, the residual maps exhibit a close match both in their anomaly patterns
and magnitudes with previously computed residual maps based on the theory of isostasy. 相似文献