Petrofacies investigations of the Cretaceous Pab Formation Rakhi Gorge Eastern Sulaiman Range Pakistan - Implication for reservoir potential

Petrologic investigations of the sixty representative thin sections from the Pab Formation within Rakhi Gorge section Eastern Sulaiman Range Pakistan have been used to characterize different diagenetic patterns, identification of primary composition and reservoir characters. Sublithic, lithic and quartzose sandstones have been the principal constituents of the formation. The processes responsible for the late-stage alteration and diagenetic processes identified during the petrographic study include compaction of lithic fragments and mud clasts, formation of quartz overgrowth structures, feldspar replacement and alteration, cementation, and replacement of grains by clay minerals other ferrous elements and diagenetic minerals. The study shows that the initial porosity has been primary intergranular, but the secondary porosity has been originated in the rocks as a result of the alteration of the primary and secondary constituents, as well as fracturing. These facies characters replicate the reservoir quality including, good, medium, low-quality, and non-reservoir. Samples displaying average total porosity greater than 10 % have been declared as good quality. While rocks samples having 7 % or greater porosity are grouped as a medium reservoir. Those samples consisting of porosity values between 1 and 4% are considered as a low quality reservoir while those samples having porosity ranges low than 1% have been called non-reservoir. Based on the investigated parameters the studied samples from the Pab Formation displayed the characters of a medium reservoir that may hold significant hydrocarbon. This different quality including good and low quality zonation can be attributed to the facies and diagenetic change in the formation.

Petrogeochemical characteristics of mafite-ultramafite rocks of the southern part of the Marunkeu block (Polar Urals)

In the Polar Urals, in the Central and Western tectonic zones, small bodies of mafic-ultramafic rocks are widespread. Their age, petrographic and geochemical features are poorly studied. The paper presents the results of petrographic and petro-geochemical study of muscovite-albite-epidote-amphibole and pyroxene-amphibole-chlorite rocks of the southern part of the Marunkeu block of the Polar Urals, localized in the Middle Riphean sediments of the Nyarovey series and presumably belonging to the Ampelshor complex (O1-2). The primary composition of metamorphites corresponded to high-magnesian, low-titanic, low-alumina, and potassium-sodium tholeiitic hornblende gabbro-dolerites (dolerites) and peridotites formed either from primary magmas melted at the level of the spinel facies from the depleted mantle under the influence of an aqueous fluid, or by intra-chamber differentiation. In terms of the contents of rare and rare-earth elements, they differ from continental riftogenic formations (in particular, dolerites of the Orangyugan-Lemva complex) and are close to the tholeiites of the ensimatic island arcs.

Accessory chrome spinels of serpentinites of tectonic melange of the Dakhov uplift (Greater Caucasus)

Особенности морфологии и состава хромшпинелидов имеют важное значение для решения ряда геологических задач: от реконструкции состава субстрата родоначальных расплавов и физико-химических условий их эволюции, установления приуроченности магматических комплексов к геодинамическим обстановкам до оценки минерагенического потенциала ультрабазитовых массивов.Цель работы– изучение акцессорных хромшпинелидов из серпентинитов тектонического меланжа на северном флангеДаховского кристаллического выступа, входящего в состав тектоническойзоны Передового хребта Большого Кавказа, выделение сохранивших исходный состав хромшпинелидов и установление условий их образования. Методы исследования: электронно-зондовый микроанализ и электронная микроскопия, статистический анализ результатов измерений. Результаты работы.Выделеныхромшпинелиды с вторичными изменениями и сохранившие исходный состав. В ходе сопровождавшей обдукциюсерпентинизацииультрабазитов (с образованием лизардит-хризотиловой ассоциации) хромшпинелиды частично трансформировались из субферрихромитов в хромиты, что сопровождалось перераспределением алюминия и магния (и обогащением внутренних зон хромом) в значительной части зерен и это в целом типично для условий низкотемпературного метаморфизма. Эти изменения выражены в образовании внешних обогащенных алюминием зон (Al2O3 более 10 вес.%) и его выносом из внутренних частей (где содержание Al2O3 неравномерное – от вариаций в пределах зерна в диапазоне 4.5-9 вес.% до менее 2% вес.%в сильно измененных разностях). Анализ корреляционныхсвязей между элементами и переход в Cr-обогащенную шпинельуказывают на преобладание двухвалентной формы железа во флюидах, что типично для восстановительных условий и высокого соотношения флюид/порода. Последующие изменения проявлены в образовании магнетитовых оторочек в окислительных условиях при интенсивной фильтрации в серпентинитах высокотемпературных гидротермальных растворов. Этот завершающий этап трансформации хромшпинелидов следует связывать с концом этапа герцинской коллизии, когда фрагменты апогипербазитовых тел, оторванные от офиолитового меланжа, были причленены к краю Даховского блока кристаллиникума, интенсивно дислоцированы и прорваны малыми интрузиями завершающей фазы гранитоидного магматизма. Интенсивное дробление и циркуляция растворов проявлены в формировании нескольких генераций магнетита, образующих тонкие пересекающиеся прожилки в серпентинитах. Первичный состав хромшпинелидов(соответствующий субферрохромитам с Cr# 0.80-0.81) указывает на их близость к типу офиолитовсупра- или надсубдукционных зон (SSZ), в частности к гарцбургитовымофиолитам фронтальных частей островных дуг, ультрабазиты которых образуются в условиях плавления деплитированойгарцбургитовой мантии Features of the morphology and composition of chrome spinels are important for solving a number of geological problems: from reconstructing the composition of the substrate of the initial melts and the physicochemical conditions of their evolution, establishing the confinement of magmatic complexes to geodynamic settings, and assessing the mineralogenic potential of ultrabasite massifs. Aim.Studying of accessory chrome spinels from serpentinites of tectonic melange on the northern flank of the Dakhovsky crystalline protrusion, which is part of the tectonic zone of the Front range of the Greater Caucasus, identify the chromium spinels that retained their original composition and determination the conditions of their formation.Methods.Electron probe microanalysis and electron microscopy, statistical analysis of measurement results.Results.Groups of grains with secondary changes and groups that retained the original composition have been distinguished. During the serpentinization of ultrabasites accompanying the obduction (with the formation of lysardite-chrysotile association), chrome spinels partially transformed from subferrichromites to chromites, it was accompanied by a redistribution of aluminum and magnesium (and enrichment of the inner zones with chromium) in a significant part of the grains and it is generally typical for conditions of low-temperature metamorphism. These changes are typical in the formation of external zones enriched with aluminum (Al2O3 more than 9 wt.%) and its removal from the internal parts (where the Al2O3content is uneven - from variations within the grain in the range of 4.5-9 wt.% to less than 2% wt.% In greatly modified differences). The transition to Cr-enriched spinel and an analysis of the correlation between the elements indicate the predominance of the divalent form of iron in the fluids, which is typical for reducing conditions and a high fluid / rock ratio. Subsequent changes can be seen in the formation of magnetite rims under oxidizing conditions during intensive filtration of high-temperature hydrothermal solutions in serpentinites. This final stage of the transformation of chrome spinels should be associated with the end of the Hercynian collision stage, when fragments of apogiperbasite bodies torn from the ophiolitemelange were attached to the edge of the Dakhov block of the crystallinum, intensively deployed and broken through by small intrusions of the final phase of granitoidmagmatism. Intensive crushing and circulation of solutions can be seen in the formation of several generations of magnetite, forming thin intersecting streaks in serpentinite. The primary composition of chrome spinels (corresponding to subferrochromites, Cr# 0.80-0.81) indicates their proximity to the type of ophiolites of supra- or suprasubduction zones (SSZ), in particular, to harzburgiteophiolites of the frontal parts of island arcs, ultrabasites of which are formed under conditions of melting of the deplicatedharzburgite mantle

Shannon Entropy as an Indicator for Sorting Processes in Hydrothermal Systems

Hydrothermal processes modify the chemical and mineralogical composition of rock. We studied and quantified the effects of hydrothermal processes on the composition of volcanic rocks by a novel application of the Shannon entropy, which is a measure of uncertainty and commonly applied in information theory. We show here that the Shannon entropies calculated on major elemental chemical composition data and short-wave infrared (SWIR) reflectance spectra of hydrothermally altered rocks are lower than unaltered rocks with a comparable primary composition. The lowering of the Shannon entropy indicates chemical and spectral sorting during hydrothermal alteration of rocks. The hydrothermal processes described in this study present a natural mechanism for transforming energy from heat to increased order in rock. The increased order is manifest as the increased sorting of chemical elements and SWIR absorption features of the rock, and can be measured and quantified by the Shannon entropy. The results are useful for the study of hydrothermal mineral deposits, early life environments and the effects of hydrothermal processes on rocks.

Covid19 Crisis, Migratory labor and their homecoming- the effect on Real Estate Sector and Travel (Hotel) Industry:an essay on Indian Perspectives.docx

This paper describes how in India all the domestic migrant labourers were seen to return home to their original village or small towns fearing the famine. As these labourers are primary composition of human capital in real estate and hotel industry, this paper discusses how the home coming of migrants brought these industries to complete standstill. Apart from this, the paper highlights the overall impact of covid19 on both the industries and the possible recovery measures that can be under taken.<br>

Covid19 Crisis, Migratory labor and their homecoming- the effect on Real Estate Sector and Travel (Hotel) Industry:an essay on Indian Perspectives.docx

This paper describes how in India all the domestic migrant labourers were seen to return home to their original village or small towns fearing the famine. As these labourers are primary composition of human capital in real estate and hotel industry, this paper discusses how the home coming of migrants brought these industries to complete standstill. Apart from this, the paper highlights the overall impact of covid19 on both the industries and the possible recovery measures that can be under taken.<br>

Silification of the Mesozoic Rocks Accompanying the Bełchatów Lignite Deposit, Central Poland

Fieldwork and exploratory study of Poland’s Bełchatów lignite deposit reveals that the Jurassic and Cretaceous sediments with overlying Neogene clays include rocks of greater hardness than the primary composition would indicate. Mineralogical and petrographic tests show the impact of secondary mineralization involving silification in particular. Transitional and carbonate rocks observed microscopically and subjected to X-ray examination show numerous polymorphic forms of silica replacing carbonate minerals. Opal types A and CT, chalcedony, quartz and microcrystalline quartz are all present. The process of silification observed is a selective and multistage one, with selective activity entailing the displacement and replacement of carbonates from older rocks, mainly Cretaceous opoka-rocks and marls, and Jurassic limestones. The opal fills tectonic fractures and has cemented cracked grains. Cathodoluminescence analysis identifies several generations of silica. The rocks have undergone advanced diagenesis as is evidenced by the recorded metasomatic reactions between minerals. They can further be assumed to be in the locomorphic stage. Such observations are relevant to efforts to reconstruct the origin of the rock matrix, and to the study of its textural features. In addition, the tests run on rocks of the lignite series would seem to be of significant value in identifying and developing associated rocks.

Modeling the Atmospheric Contribution to the Interior Characterization of sub-Neptunes and its Effect on Habitability

&lt;p&gt;As the number of confirmed exoplanets has increased, so too has the diversity in their physical parameters, namely their mass and radius. A common practice is to place these planets on a Mass-Radius diagram with various calculated density curves corresponding to some bulk composition. However, these lines don&amp;#8217;t necessarily correspond to the structure of the planet found using interior models, particularly for low mass planets with masses less than 20 M&lt;sub&gt;&amp;#8853;&lt;/sub&gt; and 4 R&lt;sub&gt;&amp;#8853;&lt;/sub&gt;, which we call &amp;#8220;sub-Neptunes.&amp;#8221; Planets in this range can have highly degenerate solutions with no solar system analog, from so-called &amp;#8220;ocean worlds&amp;#8221; to small dense cores with extended primary composition atmospheres. We have created a model that is able to cover the range of solutions possible for sub-Neptunes, with various levels of complexity for both the interior and atmosphere. This includes both an isothermal and semi-grey atmosphere, along with a high-pressure solar composition envelope when atmospheric pressures exceed approximately 1000 bar. We then apply this model to known sub-Neptunes located in the extended habitable zone of their star using a hydrogen-helium dominated atmosphere. An atmospheric escape model is used to investigate the longevity of the atmosphere and its effect on the overall habitability of the planet.&lt;/p&gt;

Apatite from NWA 10153 and NWA 10645—The Key to Deciphering Magmatic and Fluid Evolution History in Nakhlites

Apatites from Martian nakhlites NWA 10153 and NWA 10645 were used to obtain insight into their crystallization environment and the subsequent postcrystallization evolution path. The research results acquired using multi-tool analyses show distinctive transformation processes that were not fully completed. The crystallization history of three apatite generations (OH-bearing, Cl-rich fluorapatite as well as OH-poor, F-rich chlorapatite and fluorapatite) were reconstructed using transmission electron microscopy and geochemical analyses. Magmatic OH-bearing, Cl-rich fluorapatite changed its primary composition and evolved toward OH-poor, F-rich chlorapatite because of its interaction with fluids. Degassing of restitic magma causes fluorapatite crystallization, which shows a strong structural affinity for the last episode of system evolution. In addition to the three apatite generations, a fourth amorphous phase of calcium phosphate has been identified with Raman spectroscopy. This amorphous phase may be considered a transition phase between magmatic and hydrothermal phases. It may give insight into the dissolution process of magmatic phosphates, help in processing reconstruction, and allow to decipher mineral interactions with hydrothermal fluids.