Responses and positive attitudes of students towards mathematics are the key to success in learning. Therefore, teachers are required to be able to innovate in learning activities. With the rapid ...advancement of technology, it can be used as a motivation to develop innovative learning media that can support learning activities. In this study, the aim was to develop an ethnomathematics-based learning media using a valid Ispring Suite. This research is research and development with the ADDIE model which consists of 5 stages, namely analysis, design, development, implementation, and evaluation. However, in this study, the implementation was limited to the development stage. The data collection instrument in this study was a validation sheet filled out by media experts and material experts. The data analysis technique used in this research is descriptive analysis technique. Learning media is appropriate based on the assessment of media experts who get a score of 94.00% in the "Very Good" category and the results of the assessment of material experts who get a score of 95.56% in the "Very Good" category.
Context: Software regression testing refers to rerunning test cases after the system under test is modified, ascertaining that the changes have not (re-)introduced failures. Not all researchers’ ...approaches consider applicability and scalability concerns, and not many have produced an impact in practice. Objective: One goal is to investigate industrial relevance and applicability of proposed approaches. Another is providing a live review, open to continuous updates by the community. Method: A systematic review of regression testing studies that are clearly motivated by or validated against industrial relevance and applicability is conducted. It is complemented by follow-up surveys with authors of the selected papers and 23 practitioners. Results: A set of 79 primary studies published between 2016–2022 is collected and classified according to approaches and metrics. Aspects relative to their relevance and impact are discussed, also based on their authors’ feedback. All the data are made available from the live repository that accompanies the study. Conclusions: While widely motivated by industrial relevance and applicability, not many approaches are evaluated in industrial or large-scale open-source systems, and even fewer approaches have been adopted in practice. Some challenges hindering the implementation of relevant approaches are synthesized, also based on the practitioners’ feedback.
For solving constrained multiobjective optimization problems (CMOPs), many algorithms have been proposed in the evolutionary computation research community for the past two decades. Generally, the ...effectiveness of an algorithm for CMOPs is evaluated by artificial test problems. However, after a brief review of current artificial test problems, we have found that they are not well-designed and fail to reflect the characteristics of real-world applications (e.g., small feasibility ratio). Thus, in this paper, we first propose a new constraint construction method to facilitate the systematic design of test problems. Then, on the basis of this method, we design a new test suite consisting of 14 instances, which covers diverse characteristics extracted from real-world CMOPs and can be divided into four types. Considering that the comprehensive performance comparisons among the constraint-handling techniques (CHTs) remain scarce, we choose several representative CHTs and compare their performance on our test suite. The performance comparisons identify the strengths and weaknesses of different CHTs on different types of CMOPs and provide guidelines on how to select/design a CHT in a specific scenario.
The late Paleoproterozoic Jianping diorite–monzonite–syenite suite (JDMSS), in the Western Liaoning Province (WLP) along the northern margin of the North China Craton (NCC), is composed mainly of ...magnetite diorites, clinopyroxene monzonites, syenites, and quartz syenites. LA-ICP-MS zircon U–Pb isotopic dating indicates that this complex emplaced between 1696 and 1721Ma, almost synchronously with the 1680–1750Ma anorthosite–mangerite–alkali granitoid–rapakivi granite suite (AMGRS) in northern Hebei Province. The JDMSS in the WLP is the eastwards extensional part of the AMGRS in northern Hebei Province along the northern margin of the NCC. All samples from the JDMSS are characterized by a wide and continuously variable geochemical spectrum of 46.3–64.9wt.% SiO2 and 0.528–4.14wt.% MgO, with high K2O (1.080–7.01wt.%) and total alkalis (Na2O+K2O, 5.08–12.55wt.%). These rocks are enriched in LREEs and LILEs but depleted in HFSEs (Nb, Ta, and Ti), and they show negative zircon εHf(t) values of −12.6 to −0.3 and a low whole-rock initial 87Sr/86Sr value of 0.703564. These geochemical features, together with trace element modeling, suggest that all the rocks of the JDMSS were generated chiefly by fractional crystallization of a common parental magma that was derived by partial melting of an amphibole-bearing enriched subcontinental lithospheric mantle source (mixed EMI and HIMU mantle), and that the magma assimilated crustal materials during ascent and emplacement. Integrating our data with those of previous studies of the contemporaneous magmatic rocks throughout the NCC (mafic dykes, volcanic rocks, and AMGRS; 1680–1780Ma), we propose that both the northern and southern margins of the NCC, as well as the TNCO (Trans-North China Orogen), evolved under a post-collisional tectonic setting during the late Paleoproterozoic, postdating the final amalgamation of the NCC, and that the NCC at this time was probably located between Laurentia (North America and Greenland) and Siberia within the interior of the Columbia supercontinent.
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► 1696–1721Ma diorite–monzonite–syenite suite (JDMSS) in the Western Liaoning Province. ► The JDMSS consists of magnetite diorites, clinopyroxene monzonites and (quartz) syenites. ► Fractional crystallization (plus crustal contamination) from a common parental magma. ► The parental magma was derived from an enriched SCLM source (mixed EMI and HIMU). ► These rocks were evolved in a post-collisional setting postdating the NCC amalgamation.
In the Bushveld Complex of South Africa, numerous granitic and granophyric rocks termed the Lebowa Granite and Rashoop Granophyre Suites, respectively, overlie the layered ultramafic-mafic rocks of ...the Rustenburg Layered Suite. Despite their close spatial and temporal association, the granites and granophyres are often interpreted as being unrelated to the Rustenburg Layered Suite. This paper describes the transition from the uppermost Rustenburg Layered Suite into overlying granite and granophyre at three locations in the western (the Bierkraal drill core) and eastern (Diepkloof farm and Stoffberg town) limbs of the Bushveld Complex. In the western limb, a ~60 m thick transition zone bridges the petrological gap between the overlying Nebo Granite (Lebowa Granite Suite) and Upper Zone (Rustenburg Layered Suite). Across the transition zone, the composition of olivine changes from Fo6 to Fo1, clinopyroxene from Mg#25 to Mg#2 and plagioclase from An45 to An16. At Stoffberg in the eastern limb, the Upper Zone dioritic cumulates grade into the overlying monzonitic Roof Zone. Across the Roof Zone, plagioclase compositions change from An42 to An4, clinopyroxene from Mg#30 to Mg#11 and olivine from Fo9 to Fo5. Based on geochemistry and petrography, we correlate the lowermost stratigraphy at the farm Diepkloof with the Stoffberg Roof Zone. At Diepkloof, the Roof Zone grades into the overlying Stavoren Granophyre (Rashoop Granophyre Suite). All units are indistinguishable in terms of bulk rock Nd (εNd = −6.4 to −5.4) and Hf (εHf = −9.2 to −6.6) isotopes (corrected to 2055 Ma). Similarly, the Upper Main Zone, Upper Zone and transition zone are indistinguishable in terms of bulk rock Sr isotopes ((87Sr/86Sr)2055 Ma = 0.7071 to 0.7076, except one transition zone outlier at 0.7058). We submit that the transition zone represents the fossil record of bulk and/or diffusional mixing between coexisting Upper Zone and Nebo Granite magmas. We test this hypothesis by combining field, petrographic and geochemical observations with forward modelling using the Rhyolite-MELTS algorithm. Our work on the Bierkraal core (western limb) shows that at least a portion of the granitic magma was emplaced before the residual liquid of the Upper Zone had solidified. At Stoffberg and Diepkloof in the eastern limb (where the granite is absent), the Roof Zone underwent uninterrupted fractional crystallization.
•Granitic and mafic magmas co-existed in the Bushveld Complex.•The top of the Rustenburg Layered Suite has two main expressions.•In contact with granite, a transition zone is recognized.•In contact with meta-volcanic roof rocks, fractional crystallization is recognized.
ABSTRACT
Major changes in tectonic style can lead to tapping of highly variable magma sources and potentially result in significant episodes of crustal growth. Here we focus on magmatism associated ...with a transition from arc magmatism to subsequent over-thickening and eventual orogenic collapse. This transition is associated with cessation of subduction and was followed by continental extension and finally continental break-up as recorded in the Cretaceous magmatic record of Zealandia. Orogenic collapse peaked at ∼110 Ma and is expressed through core complex formation and the intrusion of I- to evolved I/S-type Rahu Suite plutons that have widely varying chemical compositions but homogeneous whole-rock and zircon isotopic signatures that are intermediate between mantle and local upper crust values. The Rahu Suite is interpreted to be derived from differing degrees of melt extraction from a pre-existing lower crustal source and lacks a demonstrable juvenile component. This lower crustal source was likely formed by magmatic underplating and melt–crust hybridization during preceding arc volcanism (Separation Point and Darran suites), effectively smearing out a pulsed event of crust formation in the zircon record. Therefore, late orogenic I- and I/S-type suites do not have to equate to crustal growth and can be an expression of crustal re-melting. An abrupt change in magma sources in Zealandia occurred after 100 Ma during the onset of progressive crustal extension. A juvenile alkaline component (presumably derived from the lithospheric mantle) is suggested to have been present from >97 Ma. This component became more pronounced with time until the emplacement of granites and trachytes with isotopic signatures overlapping with coeval mafic mantle-derived dikes during bimodal rift-related magmatism. The juvenile alkaline component dictated the composition of the felsic magmas but did not represent a significant crustal growth event due to small total volumes.
TTG rocks are commonly assumed to form by partial melting of oceanic crust during slab subduction or anatexis of thickened lower crust. The two models are tested by an integrated study of ...geochronology and geochemistry for a composite batholith of Neoproterozoic granitoids (mainly TTG-like) from the Yangtze Gorge in South China. Zircon U–Pb dating indicates that all granitoids crystallized in a period of 820 to 800 Ma. Zircon δ18O values are 4.85 to 6.84‰, suggesting limited contributions from supracrustal materials to magma sources. Zircon εHf(t) values for syn-magmatic domains range from −3.6 to −29.7, concordant with whole-rock εNd(t) values of −2.1 to −21.3. Correspondingly, zircon Hf model ages are 2.09 to 3.16 Ga, suggesting their derivation from ancient crust of Paleoproterozoic to Archean ages. TTG-like rocks contain inherited zircon cores that yield two groups of U–Pb ages at Paleoproterozoic (1.8 to 2.0 Ga) and Archean (~2.9 Ga), respectively. They show variable εHf(t) values from −48.4 to −33.4. Because the Neoproterozoic magmatism leads to variable increases of εHf(t) values for some inherited cores, only the lowest εHf(t) values for the inherited cores are assumed to represent the original Hf isotopes in source rocks. The screened results are consistent with those for Archean TTG gneiss and migmatite in this region. In addition, the TTG-like rocks have lower εNd(t) and εHf(t) values, higher Sr/Y and (La/Yb)N ratios and stronger depletion in Nb, Ta and Ti than the other granitoids. Two alternative scenarios are proposed to account for their petrogenesis: (1) anatexis of Archean and Paleoproterozoic mafic crust in the stable depths of garnet and amphibole, respectively; or (2) anatexis of Archean TTG and Paleoproterozoic mafic rocks in amphibole-stable depths. Nevertheless, the second one is preferred because the inherited zircons with Paleoproterozoic to Archean U–Pb ages are preserved in the TTG-like rocks, which is incompatible with high temperatures to generate the primary TTG magmas. Therefore, the Neoproterozoic TTG-like rocks were derived from the anatexis of ancient non-thickened lower crust, with the TTG features inheriting from their source.
The Northern Norrbotten Ore Province in northernmost Sweden includes the type localities for Kiruna-type apatite iron deposits and has been the focus for intense exploration and research related to ...Fe oxide-Cu-Au mineralisation during the last decades. Several different types of Fe-oxide and Cu-Au±Fe oxide mineralisation occur in the region and include: stratiform Cu±Zn±Pb±Fe oxide type, iron formations (including BIF's), Kiruna-type apatite iron ore, and epigenetic Cu±Au±Fe oxide type which may be further subdivided into different styles of mineralisation, some of them with typical IOCG (Iron Oxide-Copper-Gold) characteristics. Generally, the formation of Fe oxide±Cu±Au mineralisation is directly or indirectly dated between ~2.1 and 1.75Ga, thus spanning about 350m.y. of geological evolution.
The current paper will present in more detail the characteristics of certain key deposits, and aims to put the global concepts of Fe-oxide Cu-Au mineralisations into a regional context. The focus will be on iron deposits and various types of deposits containing Fe-oxides and Cu-sulphides in different proportions which generally have some characteristics in common with the IOCG style. In particular, ore fluid characteristics (magmatic versus non-magmatic) and new geochronological data are used to link the ore-forming processes with the overall crustal evolution to generate a metallogenetic model.
Rift bounded shallow marine basins developed at ~2.1–2.0Ga following a long period of extensional tectonics within the Greenstone-dominated, 2.5–2.0Ga Karelian craton. The ~1.9–1.8Ga Svecofennian Orogen is characterised by subduction and accretion from the southwest. An initial emplacement of calc-alkaline magmas into ~1.9Ga continental arcs led to the formation of the Haparanda Suite and the Porphyrite Group volcanic rocks. Following this early stage of magmatic activity, and separated from it by the earliest deformation and metamorphism, more alkali-rich magmas of the Perthite Monzonite Suite and the Kiirunavaara Group volcanic rocks were formed at ~1.88Ga. Subsequently, partial melting of the middle crust produced large volumes of ~1.85 and 1.8Ga S-type granites in conjunction with subduction related A−/I-type magmatism and associated deformation and metamorphism.
In our metallogenetic model the ore formation is considered to relate to the geological evolution as follows. Iron formations and a few stratiform sulphide deposits were deposited in relation to exhalative processes in rift bounded marine basins. The iron formations may be sub-divided into BIF- (banded iron formations) and Mg-rich types, and at several locations these types grade into each other. There is no direct age evidence to constrain the deposition of iron formations, but stable isotope data and stratigraphic correlations suggest a formation within the 2.1–2.0Ga age range. The major Kiruna-type ores formed from an iron-rich magma (generally with a hydrothermal over-print) and are restricted to areas occupied by volcanic rocks of the Kiirunavaara Group. It is suggested here that 1.89–1.88Ga tholeiitic magmas underwent magma liquid immiscibility reactions during fractionation and interaction with crustal rocks, including metaevaporites, generating more felsic magmatic rocks and Kiruna-type iron deposits. A second generation of this ore type, with a minor economic importance, appears to have been formed about 100Ma later. The epigenetic Cu-Au±Fe oxide mineralisation formed during two stages of the Svecofennian evolution in association with magmatic and metamorphic events and crustal-scale shear zones. During the first stage of mineralisation, from 1.89–1.88Ga, intrusion-related (porphyry-style) mineralisation and Cu-Au deposits of IOCG affinity formed from magmatic-hydrothermal systems, whereas vein-style and shear zone deposits largely formed at c. 1.78Ga.
The large range of different Fe oxide and Cu-Au±Fe oxide deposits in Northern Norrbotten is associated with various alteration systems, involving e.g. scapolite, albite, K feldspar, biotite, carbonates, tourmaline and sericite. However, among the apatite iron ores and the epigenetic Cu-Au±Fe oxide deposits the character of mineralisation, type of ore- and alteration minerals and metal associations are partly controlled by stratigraphic position (i.e. depth of emplacement). Highly saline, NaCl+CaCl2 dominated fluids, commonly also including a CO2-rich population, appear to be a common characteristic feature irrespective of type and age of deposits. Thus, fluids with similar characteristics appear to have been active during quite different stages of the geological evolution. Ore fluids related to epigenetic Cu-Au±Fe oxides display a trend with decreasing salinity, which probably was caused by mixing with meteoric water. Tentatively, this can be linked to different CuAu ore paragenesis, including an initial (magnetite)-pyrite-chalcopyrite stage, a main chalcopyrite stage, and a late bornite stage.
Based on the anion composition and the Br/Cl ratio of ore related fluids bittern brines and metaevaporites (including scapolite) seem to be important sources to the high salinity hydrothermal systems generating most of the deposits in Norrbotten. Depending on local conditions and position in the crust these fluids generated a variety of Cu-Au deposits. These include typical IOCG-deposits (Fe-oxides and Cu-Au are part of the same process), IOCG of iron stone type (pre-existing Fe-oxide deposit with later addition of Cu-Au), IOCG of reduced type (lacking Fe-oxides due to local reducing conditions) and vein-style Cu-Au deposits. From a strict genetic point of view, IOCG deposits that formed from fluids of a mainly magmatic origin should be considered to be a different type than those deposits associated with mainly non-magmatic fluids. The former tend to overlap with porphyry systems, whereas those of a mainly non-magmatic origin overlap with sediment hosted Cu-deposits with respect to their origin and character of the ore fluids.
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The Murrumbidgee Batholith is typical of other composite S-type granite batholiths in the Lachlan Fold Belt (LFB) of southeastern Australia, consisting of discrete peraluminous, cogenetic granite ...suites. However, it contains a unique suite (Murrumbucka) at its southern extremity that has chemical and petrological features transitional with metaluminous I-type granites. Previous detailed structural and metamorphic studies have shown that the batholith is tilted northward, exposing subvolcanic plutons in the north and root zones in the south, originally located at depths of ∼10 km. A transition from mafic, foliated, sheet-like granites in the south to felsic, generally less foliated, homogeneous granites in the north is consistent with magma ascent via subvertical, structurally controlled sheets to emplacement in an overlying magma chamber.
In the inferred root zones, the Murrumbucka Suite hosts migmatitic metasedimentary and gabbroic rocks, both of which have transitional contacts and show evidence for mafic–felsic interaction with the Murrumbucka Suite. The migmatites extend southward to become part of the high-
T, low-
P Cooma Metamorphic Complex, which contains a core of heterogeneous remobilised diatexitic granite (Cooma Suite), lenses of which also occur throughout the southern (deeper) parts of the Murrumbidgee Batholith. The composition of the most mafic rocks from the batholith lies on a chemical tie-line between Cooma Suite granites and the gabbros, for almost all elements. This chemical coincidence is interpreted to reflect derivation of parental Murrumbidgee S-type granite magmas by bulk mixing between a felsic (crustal) and mafic (mantle-derived) component, consistent with Sr and Nd isotopic results and field observations. Based on the tie-lines and simple numerical modelling, the Murrumbucka suite is estimated to be a 50:50 mix of mantle- and crustal-derived magmas, whereas the more peraluminous and widespread Clear Range Suite, which is very typical of Lachlan S-type granites, is modelled as a 40:60 mix. Chemical variation trends diverge from the mixing lines and suggest that much of the fractionation process operated after mixing. Mixing occurred within sheets during the ascent of the magmas, whereas fractionation was the dominant process generating chemical diversity during emplacement in the magma chamber. Generation of the S-type granites probably occurred in an extensional tectonic environment.
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