Flat Earth Research Articles

Protracted eclogite‐facies metamorphism of the Dulan area, North Qaidam ultrahigh‐pressure terrane: Insights on zircon growth during continental subduction and collision

AbstractContinental subduction and collision are recorded by ultrahigh‐pressure (UHP) terranes; UHP terranes that form at early stages of an orogeny tend to be small and experience short residence at eclogite‐facies depths, whereas terranes that form at mature stages of an orogeny tend to be larger and experience longer residence at these depths, but accurately determining eclogite‐facies residence time requires a large geochronologic dataset tied to metamorphic conditions (via trace elements and/or inclusions). In the Dulan area, North Qaidam UHP terrane, China, it remains unclear whether the terrane experienced a long residence at eclogite‐facies depths, marking the mature stage of an orogeny or two distinct (ultra)high pressure ([U]HP) events (with short residence times), interpreted as the transition from oceanic subduction to continental collision, where one (U)HP event is related to the former and second (U)HP event to the latter. To address this issue, we report new zircon U–Pb ages and trace‐element data from eclogite and host paragneiss from the Dulan area and show that this terrane records ~42 Myr of eclogite‐facies metamorphism at (U)HP conditions, similar to other large UHP terranes. Zircon from 11 eclogite and 2 gneiss samples yields weighted mean ages of 463–425 Ma, flat heavy rare earth element (HREE) patterns without negative Eu anomalies, and eclogitic mineral inclusions, indicating eclogite‐facies conditions. Paragneiss metamorphic ages overlap with ages from eclogite but are generally younger, suggesting that a lack of internally generated fluids may have inhibited zircon growth and/or recrystallization until early decompression and white mica consumption in felsic gneiss generated fluids; thus, we interpret that these felsic rocks record the later stages of continental collision. Dataset patterns from all new and previously published analyses for the Dulan area (34 eclogite and 14 gneiss) suggest that metamorphic zircon in eclogite records prograde, peak and possibly early retrograde conditions, in contrast to the prediction from mass balance models that metamorphic zircon should only grow during exhumation and cooling. We reconcile our observations with these model predictions by recognizing that differential solubility can lead to grain‐scale zircon growth or recrystallization over a large segment of the pressure–temperature (P–T) path even where zircon abundance decreases at the whole‐rock scale.

Geochemical Features of Volcanic Rocks from the Shaerbuti Mountain Complex, West Junggar, Xinjiang, China: Implications for Recycling of Materials

In this paper, we focus on the geological features of volcanic edifices and the geochemistry of intermediate–basic volcanic rocks of Shaerbuti Mountain, which offer a new perspective on recycled materials in the study area. The Shaerbuti volcanic rocks consist of calc-alkali basalt and andesite formed in an arc setting. The porphyroclastic texture of basalt, explosive breccia rock, and the distribution of both breccia and agglomerate provide robust evidence that a volcanic edifice exists in Shaerbuti Mountain. Based on geochemical features, the Shaerbuti volcanic rocks have been identified as being of two types. Type I volcanic rocks have light rare earth element (LREE)-enriched patterns, with La/Sm ratios of 2.27–4.03, Th/Yb ratios of 0.50–1.46, and Nb/Yb ratios of 1.11–2.28. Type II volcanic rocks display a flat rare earth element (REE) pattern, with La/Sm ratios ranging from 1.83 to 2.43, Th/Yb ratios ranging from 0.24 to 0.45, and Nb/Yb ratios ranging from 0.87 to 0.93. In the studied rocks, MgO-Cr, MgO-Ni and MgO-CaO present a positive relationship, which indicates clinopyroxenes crystallized. The Sr-Nd-Pb isotopic compositions of these basalts present values of 0.7045 to 0.7063 ((87Sr/86Sr)i), 6.4 to 6.6 (εNd(t)), and 17.1300 to 18.3477 ((206Pb/204Pb)i), respectively. According to Sr-Nd-Pb isotope features, we argue that melts of altered oceanic crust and sediments were incorporated into the source. We also evaluate the water content (0.55%–6.72%) of the studied volcanic rocks.

Motivated ignorance and social identity threat: the case of the Flat Earth

ABSTRACT Belief in a conspiracy theory may, for some, provide a social identity. Because of the nature of many conspiracy theories, social identities associated with such beliefs may be subject to varied and considerable threats. Whilst various mechanisms for dealing with social identity threat have received widespread attention, this paper introduces an as yet unexplored strategy – that of ‘motivated ignorance' – as a further mechanism for social identity maintenance. This is a behavior where individuals actively avoid freely available and accessible information in order to protect a social identity from information that may be harmful to the existence of the broader social group, and thus the individual’s own sense of self. Using a netnographic approach, we explored motivated ignorance related to the social identities formed around beliefs in the Flat Earth. Data revealed two categories of motivated ignorance. Firstly, that of ‘poisoning the well', where ignorance was justified by derogating the perceived epistemic quality of the information. The second was more instrumental, through ad hominem attacks on the source rather than the epistemic quality of information. The study suggests that motivated ignorance may be used as a strategy that may be used to protect social identities that are under threat, adding a further mechanism to the literature on coping with social identity threat.

Flat Earth: An Approach to Enhance Public Responsibility to Motor Impaired People

The concept of enhancing public responsibility to people with disabilities is to increase general awareness to understand the needs of motor-impaired people (MIP). The facts of the daily experience and possible difficulties of MIP were transformed into a tabletop game. In order to be prepared for the aging population happening in China, Flat Earth was designed as one solution that can be delivered to the public to improve individuals’ cognition of disabilities by playing as a character with limited motor ability in Flat Earth.

Ellingsen, Mark. Finding Peaks and Valleys in a Flat World

Ellingsen, Mark. Finding Peaks and Valleys in a Flat World

Ayurgenomics-based frameworks in precision and integrative medicine: Translational opportunities.

In today's globalized and flat world, a patient can access and seek multiple health and disease management options. A digitally enabled participatory framework that allows an evidence-based informed choice is likely to assume an immense importance in the future. In India, traditional knowledge systems, like Ayurveda, coexist with modern medicine. However, due to limited crosstalk between the clinicians of both disciplines, a patient attempts integrative medicine by seeking both options independently with limited understanding and evidence. There is a need for an integrative medicine platform with a formalized approach, which allows practitioners from the two diverse systems to crosstalk, coexist, and coevolve for an informed cross-referral that benefits the patients. To be successful, this needs frameworks that enable the bridging of disciplines through a common interface with shared ontologies. Ayurgenomics is an emerging discipline that explores the principles and practices of Ayurveda combined with genomics approaches for mainstream integration. The present review highlights how in conjunction with different disciplines and technologies this has provided frameworks for (1) the discovery of molecular correlates to build ontological links between the two systems, (2) the discovery of biomarkers and targets for early actionable interventions, (3) understanding molecular mechanisms of drug action from its usage perspective in Ayurveda with applications in repurposing, (4) understanding the network and P4 medicine perspective of Ayurveda through a common organizing principle, (5) non-invasive stratification of healthy and diseased individuals using a compendium of system-level phenotypes, and (6) developing evidence-based solutions for practice in integrative medicine settings. The concordance between the two contrasting streams has been built through extensive explorations and iterations of the concepts of Ayurveda and genomic observations using state-of-the-art technologies, computational approaches, and model system studies. These highlight the enormous potential of a trans-disciplinary approach in evolving solutions for personalized interventions in integrative medicine settings.

МЕДИСТЫЕ СЛАНЦЫ ПРИКОЛЫМСКОГО ТЕРРЕЙНА (СЕВЕРО-ВОСТОК РОССИИ): МИНЕРАЛОГО-ГЕОХИМИЧЕСКИЕ ОСОБЕННОСТИ И УСЛОВИЯ РУДООБРАЗОВАНИЯ

Copper mineralization in the Magadan region (North-East of Russia) has been established in quartz-chloritoid and chlorite shales of the middle and upper Riphean of the Prikolymsky terrane. Compared to the upper crust, copper shales of the Oroek deposit are noticeably enriched in a narrow range of trace elements: Cu, Ag, Au, Rh, and Se, with enrichment factors ranging from 10-fold (Se, Rh) to 100-fold (Ag, Au) and even 1000-fold (Cu) suggesting, apparently, their synchronous involvement in ore formation. In addition, the studied samples are slightly enriched in Cd, Li, Co, Zn, V, U, Sc, Y, and REE. Copper shales show relatively flat rare earth element (REE) patterns similar to the chondrite-normalized pattern having no distinct positive or negative Eu anomalies and dominated by light lanthanides. The Ce/Ce* and Eu/Eu* values indicate that ore formation proceeded under oxidizing conditions. The obtained geochemical data show that the Riphean host rocks could serve as a source of trace elements and REE ore-forming fluids. In the ores, covellin and chalcocite are the main copper minerals; less common are roxbyite, idaite, nukundamite, spioncopite, chalcopyrite, silver-bearing (Ag about 1 wt. %) bornite and yarrovite, as well as native gold. Fluid inclusions in quartz suggest that copper mineralization was formed at temperatures of 212–190 °C and a pressure of 1 kbar, from hydrothermal solutions of medium salinity (from 13.8 to 12.4 wt. % eq. NaCl) and high density (0.95–0.98 g/cm3) saturated with chlorides of Ca, Mg, and K. The copper shales of the Prikolymsky terrane differ from sedimentary copper and copper shales of the African Belt by low Co and Ni contents and from the Kupfershifer by low concentrations of Pb and Zn. The obtained results can be used for prognosticating new deposits.

Spherical Earth Based Measurement Modeling for Practical OTHR Target Tracking

We revisit the problem of modeling of the over-the-horizon radar (OTHR) target tracking. The accuracy of target kinematic and measurement models are critical factors affecting tracking performance. In most of the existing literature, a flat Earth OTHR measurement model is used. This has two obvious drawbacks: (1) a state vector with components of ground range, range-rate, bearing, and bearing-rate cannot be used directly in common kinematic models such as the nearly constant velocity (NCV), nearly constant acceleration (NCA), nearly constant turn (NCT), and a combination of these. (2) The curvature of Earth is ignored, which affects the measurement accuracy of the OTHR. We develop a spherical Earth based measurement model. First, the target kinematic state is modeled in a two-dimensional tracker coordinate frame (T frame), which is suitable for the common kinematic models. Second, the measurement modeling is completed using the spherical Earth model, which fully considers the curvature of Earth among the receiver, transmitter, and target. Furthermore, the inverse mapping for track initiation is derived. Finally, the effectiveness of the developed model is demonstrated by a non-maneuvering target moving with the NCV motion and a maneuvering target moving with a sequence of NCV, NCT, and NCV motions. The interacting multiple model (IMM) algorithm is used for state estimation of the maneuvering target. The unscented Kalman filter (UKF), cubature Kalman filter (CKF), and quadrature Kalman filter (QKF) are compared for state estimation.

Study of Integrated Crop-targeted Production Efficient Fertilizer Uptake Response

The targeted pattern of multi-crops in investigation, control and treatment blocks emphasize on different crops or integrated approach to farming system in same field at temporal shift in cropping season. Studies and researches through programmes on “Integrated Farming System” paves and does incursion towards re-engineering process in plans and programme structure under farming systems mode. This gamut of framework led to neo institutional birth, through rigorous investigations of past models, approaches, plans, systems by analysis of productivity, viability and constraints prevailing. Designs of resource efficient, efficacious, economic farming system models and proto-modules for different farming scenario have been developed, in temporal dimensional shift of Kharif, Rabi and Zaid. Stoichiometric analysis-based use of balanced uptake fertilizers is done to meet the targeted productivity. Regression analysis and optimization models, equations, quasi-newton method and Jacobi method, amongst others , and conditions and constraints further give boost towards targeted yield productivity of integrated crops in contingency, feasibility and brisk growth , developmental choice models for thriving and succeeding in agriculture scenario through rolling a successful agricultural Integrated Farming System model and approach, with systems intelligence , thinking and technology at core of heart driving simplicity, spirituality and sustainability of global flat world agricultural productivity, in sync and harmony with mother earth.

Early dolomitization and subsequent hydrothermal modification of the middle Permian Qixia Formation carbonate in the northwest Sichuan Basin

High-quality dolomite reservoir are widely developed in Permian Qixia Formation in northwest Sichuan Basin. Understanding the genesis of dolomite is significant to predicting high-quality reservoir distribution. Based on the petrographical and geochemical characteristics, three types of dolomites and one type of dolomite cement were identified in the Qixia Formation in northwest Sichuan Basin: micritic to fine-crystalline dolomites (D1), medium-crystalline dolomite (D2), medium-to coarse-crystalline dolomite (D3) and saddle dolomite cement.Type D1 dolomites are characterized by micritic to fine-sized crystals, lamellar structure, generally dull to no luminescence, and relatively high strontium (Sr) concentrations. These characteristics suggest that type D1 dolomites were initially formed during the penecontemporaneous phase. The wide range of depleted δ18O values, slightly higher 87Sr/86Sr ratios and slightly positive europium (Eu) anomalies indicate that type-D1 dolomites were subsequently subjected to hydrothermal modification. Type D2 dolomite is characterized by unimodal middle-sized crystals and crystal texture dominated by nonplanar crystals. It usually occurs as thin or thick layers in the study area. The δ18O and δ13C values of type D2 dolomite generally fall within the estimated Middle Permian marine dolomite and show a significantly positive offset compared to those of coeval seawater. The 87Sr/86Sr ratios of type D2 dolomite are slightly higher than the coeval seawater. These features combined with the flat rare earth element (REE) profile and relatively high Sr concentrations (both are similar to the host limestone) indicate that type D2 dolomites first precipitated in the slightly evaporated Middle Permian seawater during the near-surface to shallow burial phase. Type D3 dolomites are mainly characterized by interlocking mosaic crystals with crystal sizes varying from 300 μm to 900 μm. It mainly occurs as patches in type D2 dolomites or as a thick layer sandwiched by type D2 dolomites. These features combined with its high 87Sr/86Sr ratios, δ18O depletion and positive Eu anomalies (which are very similar to those of the saddle dolomites) demonstrate that it is formed by hydrothermal recrystallization upon type D2 dolomites. Saddle dolomite generally occurs as the filling cement of pores, vugs, and fractures and is usually combined with matrix dolomite to form zebra dolomite and hydrothermal dolomite breccia. It has a curve crystal face, demonstrates wavy extinction under cross-polarization and red luminescence under a cathodoluminescence microscope. These features, together with the highest Th, most negative δ18O value and highest 87Sr/86Sr ratio compared to those of all types of dolomites in the study area as well as the positive Eu anomalies suggest that it should have been formed by hydrothermal fluid precipitation.Type D1 and type D3 dolomites are volumetrically minor and the pores are poorly developed. Saddle dolomite cemented and filled the pores and vugs of matrix dolomite, resulting in reservoir damage. Type D2 dolomites constitute the main body of high-quality reservoir in Qixia Formation. It precipitated in the slightly evaporated penesaline Middle Permian seawater during the near-surface to shallow burial phase. Potential high-quality reservoirs may occur in the shoal around the limited inter-shoal sea.

Everything causes cancer? Beliefs and attitudes towards cancer prevention among anti-vaxxers, flat earthers, and reptilian conspiracists: online cross sectional survey

ObjectiveTo evaluate, using an online non-probability sample, the beliefs about and attitudes towards cancer prevention of people professing vaccination scepticism or conspiracy theories.DesignCross sectional survey.SettingData collected mainly from ForoCoches (a...

Problematika Bentuk Bumi: Kajian Komparatif Historis Sains Serta Perspektif Al-Qur’an Dan Sunnah

This article discusses the problems of the shape of the earth: a comparative historical study of science and the perspective of the Qur'an and Sunnah. Among the scientific studies that are quite warm and test the existence of modern science in recent years is the debate between adherents of the spherical Earth theory (spherical and ellipsoid) and adherents of the flat Earth theory (flat earth). This issue becomes a very serious problem because each party not only shows scientific evidence, but also uses the arguments of the Qur'an and hadith to strengthen their arguments. From a scientific point of view, flat-Earthers argue against the spherical Earth theory such as the invisible curvature of the Earth based on Samuel Rowbotham's experiments, claims that NASA fabricated photos of the Earth and satellites are mere lies, there is no gravity, the north pole is the center of the Earth and so on. Other Meanwhile, in terms of syar’i texts, the commentators also differ in opinion about how the Earth actually looks like. What was put forward by adherents of flat earth was then responded by adherents of round Earth with a number of scientific arguments. In this paper, the authors present a comparison between the flat earth theory and rebuttals from adherents of the spherical earth theory in several approaches, such as the development of history, science, the study of astronomy and interpretation of the Qur'an.

3D minimum-structure inversion of controlled-source EM data using unstructured grids

In this study, a minimum-structure inversion procedure for controlled-source electromagnetic data that parameterizes the Earth model in terms of an unstructured tetrahedral grid is presented. To minimize the objective function defining the inversion problem Gauss–Newton iterations are used. Iterative solvers are employed for the solution of the system of equations at each Gauss–Newton step. These solvers do not need the matrix to be explicitly formed to solve the linear system, and hence, these kinds of solvers ensure memory efficiency of the developed algorithm. For the forward-modelling problem, a potentials formulation, in which the electric field is expressed in terms of vector and scalar potentials and the relevant partial differential equations are the Helmholtz and conservation of charge equations, is discretized by the finite-element method. This decomposition results in a well conditioned matrix equation compared to the E-field equation and gives a more natural description of electromagnetic phenomena. The linear system of equations for the forward-modelling problem is solved by a direct solver. The advantage of this type of solver is that the factorization that is generated, which takes up the bulk of the solution time for this system, can be reused when solving for multiple right-hand sides. This is important for the efficient calculation of the matrix–vector products in the above-mentioned Gauss–Newton systems. Two synthetic examples are given to illustrate the capabilities and efficiency of the presented procedure. In the first example, inversion of a dataset generated over a geometric shaped conductive body for a flat Earth’s surface is presented. In the second example, a realistic scenario is given. This example shows that topography and a realistic ore body can be naturally and effectively handled by unstructured grids.

Spatial growth theory: Optimality and spatial heterogeneity

Spatiotemporal dynamics are introduced in a standard Ramsey model of optimal growth in which capital moves toward locations where the marginal productivity of capital is relatively higher and initiate a study of the effects of nonlinear capital transport in terms of a linearized analysis around steady state solution solutions.The potential spatial heterogeneity of optimal growth, as seen from the point of view of an optimizing social planner, is examined. Our results suggest that for a high utility discount rate, the spatial capital flows induce the emergence of optimal spatial patterns, while for a low utility discount, a flat earth steady state is socially optimal. Furthermore, when spatial heterogeneities exist due to total factor productivity differences across locations, we identify conditions under which the spatial capital flows could intensify or weaken spatial inequalities.

Shidian meteorite, a new fall analog of near‐Earth asteroid (101955) Bennu

AbstractShidian is a recent meteorite which fell in Yunnan province, China, on November 27, 2017, and has been classified as a CM2 chondrite. Petrography, mineralogy, oxygen and chromium isotopic composition, reflectance spectrum, and density studies of Shidian are reported in this study. Clasts with different aqueous alteration degree, two type 1 clasts with nontypical CM petrography, and one metamorphic clast are observed in Shidian. Mineralogically, Shidian main body consists of phyllosilicates (∼70 vol%), forsterite (∼13 vol%), fayalitic olivine, carbonates, sulfide, high‐Ca pyroxene, magnetite framboids, and Fe‐Ni metal. The average electron microprobe analysis (EMPA) analytical totals of phyllosilicates are 84.07 ± 1.75 wt%, with average FeO/SiO2of tochilinite–cronstedtite intergrowths (TCIs) in different clasts ranging from 1.18 to 3.29. The bulk geochemical composition is characterized by flat rare earth element pattern, and by depletion of highly volatile elements. The whole rock oxygen isotopic composition is −0.51 ± 0.73‰, 5.44 ± 1.01‰, and −3.38 ± 0.20‰ for δ17O, δ18O, and Δ17O, respectively, with bulk chromium isotopic composition as ε54Cr = 1.00 ± 0.11. The grain density, bulk density, and porosity are 2.758 ± 0.008 g cm−3, 2.500 ± 0.004 g cm−3, and 9.37 ± 0.59%, respectively. The reflectance spectrum shows “blue” (negative) continuum slope across the visible and near‐infrared range, with characteristic absorption features (such as 0.765, 0.923, and 1.160 μm for phyllosilicates). These characteristics indicate that Shidian is an unheated, brecciated CM chondrite and may be an analog of asteroid Bennu.

Petrogenesis of low-pressure intra-oceanic arc granitoids: Insights from the late Neoproterozoic Avalonian–Cadomian orogen, Bohemian Massif

The processes leading to the formation of siliceous (intermediate to felsic) magmatic rocks from juvenile sources within intra-oceanic island arcs govern the formation of continental crust and tempos of crustal growth. To unravel the predominant process responsible for the formation of the intermediate to felsic intra-oceanic arc crust, we performed inverse geochemical modelling using major elements and fluid-immobile trace elements. Subvolcanic trondhjemite from a volcanic arc – Davle volcanic complex (DVC) situated in the Teplá–Barrandian unit, Bohemian Massif – that formed during the Neoproterozoic Avalonian–Cadomian orogeny was used as a proxy for the most felsic endmember of the tonalite–trondhjemite suite. The DVC trondhjemite that follows the calc-alkaline trend is enriched in several fluid-mobile elements such as Cs, Ba and U, but depleted in high field strength elements (Nb, Ti) and lithophile elements (e.g., K, Rb, Sr and Th), and exhibits flat rare earth element (REE) primitive mantle-normalized distributions with slightly negative Eu anomalies. Together with the largely radiogenic Hf-Nd isotopic signatures (ε Nd +6.0 to +8.7 and ε Hf +10.2 to +11.7), these data indicate formation in an intra-oceanic arc setting with no significant assimilation of older crustal material. In general, the composition of the studied trondhjemite markedly resembles that of other intra-oceanic arc-derived tonalites and trondhjemites worldwide, formed at low pressures below the garnet stability field. These are herein referred to as “low-pressure intra-oceanic arc granitoids” or “LP IOAG”. The performed inverse geochemical modelling revealed that dehydration partial melting or fractional crystallization of a mafic source can produce a primitive tonalitic melt. Consequently, fractional crystallization of that melt accounts for the compositional heterogeneity observed within the tonalite–trondhjemite suite. We conclude that LP IOAG, commonly forming large portions of intra-oceanic arc middle crust, can form in a nearly closed system with a negligible contribution of subduction-related melts or assimilation of older siliceous crust. Therefore, our findings suggest that the formation of LP IOAG within oceanic crust may represent the predominant process of post-Archean crustal growth. • The DVC trondhjemite has flat REE patterns resembling typical LP IOAG. • The LP IOAG play a key role in the post-Archean crustal growth. • The source composition is established by an inverse geochemical modelling. • The trondhjemite formed by fractional crystallization of a tonalitic source.

Formation of the Nephrite Deposit With Five Mineral Assemblage Zones in the Central Western Kunlun Mountains, China

Abstract The Saidikulam nephrite deposit, which is famous for its high-quality white nephrite no matter in history and nowadays, is located in the eastern part of the Western Kunlun Orogen, in the northwestern margin of the Tibetan Plateau, Yutian County, Xinjiang, China. Field investigations and petrographic observations revealed the presence of five mineral assemblage zones from granodiorite to dolomitic marble in the Saidikulam nephrite deposit: slightly epidote-altered granodiorite → epidote-altered diopsidite → nephrite → calcite tremolitite → calcite-bearing dolomitic marble. However, little is known about the relationships among these five zones or the formation age of the deposit. The slightly epidote-altered granodiorite consists of plagioclase, orthoclase, quartz, biotite, and epidote, with accessory apatite, zircon, and allanite. They exhibit slightly negative Eu anomalies (0.69–0.72), with declined light rare earth element (LREE) and flat heavy rare earth element (HREE) patterns. They are also strongly enriched in Rb, Zr, U, and Sm and depleted in Hf, Ti, P, and Nb. The epidote-altered diopsidite close to the granodiorite intrusions is a relatively high-temperature metasomatic rock composed of Fe-rich diopside and actinolite, while the calcite tremolitite adjacent to the dolomitic marble is a relatively low-temperature rock composed of prismatic tremolite and calcite. The main mineral component of the nephrite is tremolite, with minor epidote, chlorite, apatite, calcite, graphite, and allanite. The nephrites have low ∑REE contents (4.38–18.53 ppm), with declined LREE and flat HREE patterns. All of the analyzed nephrite exhibits pronounced negative Eu anomalies (δEu = 0.20–0.82), and they are strongly enriched in Rb, U, and Ti and relatively depleted in Ba and HFSEs. SHRIMP U–Pb dating of zircons from the granodiorite yielded a Concordia age of 453.8 ± 3.7 Ma, which is interpreted as the upper limit of the Saidikulam nephrite formation age. The zircons in the epidotized syenite in the deposit yielded a SHRIMP Concordia U–Pb age of 489.2 ± 4.2 Ma. These two ages indicate that the dolomitic marble experienced at least two thermal events. The approximate ages of the nephrite deposits along the giant Kunlun-Altyn Tagh belt indicate that the closure of the Proto-Tethys may have been the predominant driving force for the formation of the whole nephrite deposits. The multistage metasomatism and the Fe absorption of epidote-altered diopsidite had a positive impact on the formation of high-quality nephrite.

Controversy over the Round Earth and the Flat Earth on the Interpretation of the Qur'an: Study Interpretation with a Scientific Approach

Abstract[Controversy over the round earth and the flat earth on the interpretation of the Qur’an: study interpretation with a scientific approach] This article discusses the interpretation related to the Qur'anic verses about the round and flat earth, through a scientific approach (bil ilmi) this study uses a qualitative method of comparative studies with shorts. The data source is the book "Tafsir ilmi" of the Ministry of Religion of the Republic of Indonesia and LIPI and "Tafsir Salman" as a comparison and equalization of the related that will be discussed.data collection techniques using the search method by means of contect analysis. This article finds that one of the problems that has been developing lately is the debate regarding the shape of our earth, whether round or flat. The knowledge that has been known to people is that the earth is round, but it also develops the understanding that the earth is flat or also called the understanding of flat earth Some scholars have actually discussed this, they are discussing the issue of the shape of the earth from the perspective of sharia.Surely they postulate with those implied in the verses of the Quran and the hadith of the Prophet Sallallahu'alaihi Wasallam which preaches about this universe.
 ملخص[[جدل الأرض المستديرة والأرض المسطحة في تفسير القرآن: دراسة التفسير بمنهج علم]يناقش هذا المقال تفسير آيات القرآن عن الأرض المستديرة والمسطحة من خلال منهج علمي (بالعلم) ، وتستخدم هذه الدراسة المنهج النوعي للدراسة المقارنة مع منهج مراجعة الأدبيات. مصادر البيانات هي كتاب "تفسير علمي" لوزارة الدين بجمهورية إندونيسيا و LIPI وكذلك كتاب "تفسير سلمان" كمقارنة ومعادلة فيما يتعلق بما سيتم مناقشته. تستخدم تقنية جمع البيانات طرق البحث والبيانات. تقنيات التحليل عن طريق تحليل المحتوى (تحليل المحتوى). تجد هذه المقالة أن إحدى القضايا التي يتم تطويرها حاليًا هي الجدل حول شكل أرضنا ، سواء كانت مستديرة أو مسطحة. المعرفة التي يعرفها الناس عمومًا حتى الآن هي أن الأرض كروية ، ولكن هناك أيضًا فهم بأن الأرض مسطحة أو تُعرف أيضًا باسم فهم الأرض المسطحة. لقد ناقش بعض العلماء هذا الأمر بالفعل ، فقد ناقشوا مسألة شكل الأرض من منظور شرعي. بالطبع هم افترضوا ما ورد في آيات القرآن وحديث النبي صلى الله عليه وسلم الذي بشر عن هذا الكون.
 Abstrak[Kontroversi bumi bulat dan bumi datar pada penafsiran Alqur’an: studi tafsir dengan pendekatan sains]Artikel ini membahas penafsiran terkait ayat Al-qur’an tentang bumi bulat dan datar, dengan melalui pendekatan sains (bil ilmi) kajian ini menggunakan metode kualitatif studi komparasi dengan pendekatan kajian pustaka. Sumber data merupakan buku “Tafsir ilmi” kemenag RI dan LIPI serta “Tafsir Salman”sebagai perbandingan dan menyamakan terkait yang akan dibahas.tehnik pengumpulan data menggunakan cara penelusuran dan tehnik analisis data dengan cara analisis isi (contect analysis). Artikel ini menemukan bahwa salah satu masalah yang sedang berkembang akhir-akhir ini adalah perdebatan mengenai bentuk bumi kita, apakah bulat ataukah datar. Pengetahuan yang selama ini diketahui umumnya orang adalah bahwa bumi itu bulat, namun berkembang juga pemahaman bahwa bumi itu datar atau disebut juga pemahaman flat earth. Beberapa ulama sebenarnya telah membahas hal ini, mereka membahas masalah bentuk bumi dari perspektif syariat. Tentunya mereka berdalil dengan yang tersirat dalam auat-ayat Al-Quran dan hadits Nabi Shallallahu’alaihi Wasallam yang mengabarkan tentang alam semesta ini.

Lithospheric thinning and ignition of a Cordilleran magmatic flare-up: Geochemical and O-Hf isotopic constraints from Cretaceous plutons in southern Korea

Northeast Asian continental margins contain the products of magma emplacement driven by prolonged subduction of the (paleo-)Pacific plate. As observed in many Cordilleran arcs, magmatic evolution in this area was punctuated by high-volume pulses amid background periods. The present study investigates the early evolution of the Cretaceous magmatic flare-up using new and published geochronological, geochemical, and O-Hf isotope data from plutonic rocks in the southern Korean Peninsula. After a long (∼50 m.y.) magmatic hiatus and the development of the Honam Shear Zone through flat-slab subduction, the Cretaceous flare-up began with the intrusion of monzonites, granodiorites, and granites in the inboard Gyeonggi Massif and the intervening Okcheon Belt. Compared to Jurassic granitoids formed during the former flare-up, Albian (∼111 Ma) monzonites found in the Eopyeong area of the Okcheon Belt have distinctly higher zircon εHf(t) (−7.5 ± 1.3) and δ18O (7.78‰ ± 0.25‰) values and lower whole-rock La/Yb and Sr/Y ratios. The voluminous coeval granodiorite and granite plutons in the Gyeonggi Massif are further reduced in Sr/Y and to a lesser extent, in La/Yb, and have higher zircon εHf(t) values (−13 to −19) than the Precambrian basement (ca. −30). These chemical and isotopic features indicate that Early Cretaceous lithospheric thinning, most likely resulting from delamination of tectonically and magmatically overthickened lithospheric keel that was metasomatized during prior subduction episodes, and consequent asthenospheric upwelling played vital roles in igniting the magmatic flare-up. The O-Hf isotopic ranges of synmagmatic zircons from the Albian plutons and their Paleoproterozoic and Jurassic inheritance attest to the involvement of lithospheric mantle and crustal basement in magma generation during this decratonization event. Arc magmatism then migrated trenchward and culminated in the Late Cretaceous, yielding widespread granitoid rocks emplaced at shallow crustal levels. The early Late Cretaceous (94–85 Ma) granites now prevalent in Seoraksan-Woraksan-Sokrisan National Parks are highly silicic and display flat chondrite-normalized rare earth element patterns with deep Eu anomalies. Synmagmatic zircons in these granites mimic their host rock’s chemistry. Delamination-related rejuvenation of crustal protoliths is indicated by zircon εHf(t) values of granites (−6 to −20) that are consistently higher than the Precambrian basement value. Concomitant core-to-rim variation in zircon O-Hf isotopic compositions reflects a typical sequence of crustal assimilation and fresh input into the magma chamber.

A geochemical and mineral chemical assessment of sediment provenance and post-depositional alteration of auriferous conglomerates in the Singhbhum Craton

The Mesoarchean Dhosrapahar Group and the Phuljhari Formation in the Singhbhum Craton host so far subeconomic gold occurrences in metaconglomerate beds, similar to the world-famous conglomerate-hosted gold deposits of the Mesoarchean Witwatersrand Basin in South Africa. In the studied metaconglomerates from India, gold occurs as invisible inclusions in pyrite and as native gold grains associated with detrital chromite, quartz, zircon and metamorphic chlorite. Unlike most Archean paleoplacer deposits, the inferred detrital gold here appears unrelated to detrital pyrite, thereby highlighting the decoupling of the sources for the various placer components. To this end, we attempt to delineate the possible source rocks and assess the extent of post-depositional alteration to better understand the controls on gold accumulation in these conglomerates. Elevated Ni, Co and As, to a lesser extent V, Cu, and Se contents in Au-bearing inclusion-rich detrital pyrite are suggested to be derived from Paleoarchean banded cherts in the Gorumahisani Greenstone Belt. Relatively immobile trace element ratios, as recorded by the conglomerate matrix, reflect a predominantly felsic source with minor sediment input from mafic/ultramafic sources. Fractionated chondrite-normalized light rare earth and flat heavy rare earth element patterns, along with a distinct negative Eu-anomaly, obtained for the samples from the Phuljhari Formation point to a differentiated felsic source, most likely the c. 3.05 Ga K-rich Mayurbhanj Granite. In contrast, depleted heavy rare earth element patterns and a weak negative Eu-anomaly in the conglomerates from the Dhosrapahar Group indicate derivation from a felsic source that had experienced garnet fractionation, the obvious candidate being the underlying c. 3.37 Ga Rairangpur tonalite-trondhjemite-granodiorite (TTG) suite. Detrital rutile is rich in Cr and V, and Zr-in-rutile geothermometry yielded crystallization temperatures between ~800 and 1000 °C. The most likely source of this rutile are 3047±17 Ma gabbro-anorthosite bodies in the basement. Post-depositional modification of the conglomerates is dominantly manifested as greenschist-facies metamorphic overprint, and is reflected also by detrital chromite texture and chemistry, and the occurrence of secondary rutile, euhedral pyrite, and secondary gold with metamorphic chlorite. Our provenance interpretations do not indicate any likely point-source of detrital gold, suggestive of the entire Archean hinterland, irrespective of composition, as a potential source, as already indicated for the Mesoarchean auriferous conglomerates of the Witwatersrand Basin. This contention is further substantiated by the evidence presented here for moderate-to deep chemical weathering of the Archean hinterland of the Singhbhum Craton.