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This article focuses on how newcomers form social relations when settling in the UK, and the role of these relations in regards to their sense of belonging as well as access to resources that support integration. By bringing together the concept of social integration with scholarship on embedding and sociabilities of emplacement, the article demonstrates how a combination of serendipitous encounters, ‘crucial acquaintances’ and more enduring friendships with other migrants, co-ethnics and members of the majority population support migrants’ settlement. Drawing on two qualitative studies on migrant settlement, it shows the importance of social relations with other migrants during settlement, and subsequently critically reflects on how the notion of ‘bridging social capital’ has been used in policy discourse. By doing so, the article contends that the notion of ‘integration’ needs to reflect the social ‘unit’ into which migrants are supposed to integrate.

The environmental severity of large impacts on Earth is influenced by their impact trajectory. Impact direction and angle to the target plane affect the volume and depth of origin of vaporized target, as well as the trajectories of ejected material. The asteroid impact that formed the 66 Ma Chicxulub crater had a profound and catastrophic effect on Earth’s environment, but the impact trajectory is debated. Here we show that impact angle and direction can be diagnosed by asymmetries in the subsurface structure of the Chicxulub crater. Comparison of 3D numerical simulations of Chicxulub-scale impacts with geophysical observations suggests that the Chicxulub crater was formed by a steeply-inclined (45–60° to horizontal) impact from the northeast; several lines of evidence rule out a low angle (<30°) impact. A steeply-inclined impact produces a nearly symmetric distribution of ejected rock and releases more climate-changing gases per impactor mass than either a very shallow or near-vertical impact. The authors here present a 3D model that simulates the formation of the Chicxulub impact crater. Based on asymmetries in the subsurface structure of the Chicxulub crater, the authors diagnose impact angle and direction and suggest a steeply inclined (60° to horizontal) impact from the northeast.

The presence of recently intruded granites at Earth's surface suggests that their exhumation may have occurred rapidly. The Neogene granites of the Tuscan Magmatic Province (Italy) were emplaced during a period of extensional tectonics and are ideal for determining and quantifying the exhumation process. The peraluminous monzogranite of Giglio Island in the northern Tyrrhenian Sea is characterized by the presence of roof pendants, xenoliths and miarolitic cavities. The petrologic study of metamorphic xenoliths and new zircon U-Pb ages show that the granite was emplaced at 6.4-10 km depth at 5.7 ± 0.4 Ma. Exhumation, constrained by apatite (U-Th)/He ages, was essentially complete in 0.9 Myr at a minimum rate of 6 mm/year. This requires rapid tectonic unroofing, isostatic rebound and thermal softening activity, weakening the upper crust and favouring exhumation at a previously undocumented rate.

Igneous sill intrusions are common features in volcanic basins worldwide, constituting important components of basin‐scale magma plumbing systems. While sills exhibiting simple geometries, such as saucer‐shaped sills, are commonly linked to distinct mechanical processes, emplacement mechanisms for sills exhibiting more complex geometries are debated. To better understand the emplacement of complex sills, this study aims to constrain the formation mechanisms associated with the Infinity Sill, a 237 km2 elongated sill located in the SW Vøring Basin. Detailed seismic interpretation and attribute analysis of an industry‐standard 15,000 km2 3D seismic data set reveal that the 36 km long and 4–8 km wide Infinity Sill intruded mud‐dominated Late Cretaceous strata. The thickness of the sill has been estimated to be dominantly 50–150 m, with a volume of ∼20 km3 (ranging between 7.9 and 25.5 km3). The shape of the sill and geometry of the sill elements suggest that the sill propagated as a large, magma‐filled fracture exploiting a pre‐existing polygonal fault network during propagation. The sill originated at a source in the SW, and the asymmetric propagation away from the source facilitated a 36 km lateral elongation of the sill, contrasting along‐axis dike models for elongated intrusion geometries. Local deformation around the sill initially facilitated continuous transgression, but with increasing sill length, forced folding of the overburden triggered abrupt transgression of the sill margins, resulting in a lateral change in geometry. The Infinity Sill, with its distinct geometrical features and changing cross‐sectional geometry, demonstrates that complex sill geometries are formed by a combination of emplacement mechanisms.

Platinum-group element (PGE) deposits in the Bushveld Complex and other layered intrusions form when large, incompletely solidified magma chambers undergo central subsidence in response to crustal loading, resulting in slumping of semi-consolidated cumulate slurries to the centres of the intrusions and hydrodynamic unmixing of the slurries to form dense layers enriched in sulfides, oxides, olivine and pyroxene and less dense layers enriched in plagioclase. The most economic PGE, Cr and V reefs form in large, multiple-replenished intrusions because these cool relatively slowly and their central portions subside prior to termination of magmatism and complete cumulate solidification. The depth of emplacement has to be relatively shallow as, otherwise, ductile crust would not be able to flex and collapse. In smaller intrusions, cooling rates are faster, subsidence is less pronounced and, where it occurs, the cumulate may be largely solidified, resulting in insignificant mush mobility and mineral sorting. Layering is thus less pronounced and less regular and continuous and the grades of the reefs are lower, but the reefs can be relatively thicker. An additional factor controlling the PGE, Cr and V prospectivity of intrusions is their location within cratons. Intra-cratonic environments offer more stable emplacement conditions that are more amenable to the formation of large, layered igneous bodies. Furthermore, intrusions sited within cratons are more readily preserved because cratons are underlain by thick, buoyant keels of harzburgite that prevent plate tectonic recycling and destruction of crust.

Magma reservoirs typically form through the incremental emplacement of smaller magma pulses over extended timescales. Pulsed reservoir growth significantly impacts a magma body's temperature evolution, chemical differentiation potential, and the probability, scale, and timing of volcanic eruptions. Moreover, the addition of thermal energy and magmatic fluids reheat and hydrothermally alter previously emplaced magma. Consequently, it may be difficult to distinguish individual magma pulses in exposed solidified intrusions (plutons), obscuring evidence of magma body construction and evolution. In this study, we employ geological mapping combined with petrofabric and Anisotropy of Magnetic Susceptibility (AMS), Anisotropy of Anhysteretic Remanent Magnetization (AARM), hysteresis, First‐Order Reversal Curves (FORCs) and susceptibility versus temperature analyses to investigate pulsed magma emplacement and its consequences in terms of fabric overprinting and hydrothermal alteration within the Slaufrudalur pluton in Southeast Iceland. The field mapping documents distinct emplacement styles, including magma ascent in marginal zones, subhorizontal sheet emplacement, and bulk intrusion below the sheets. The AMS fabrics show high Km values (∼1 × 10−2 SI), but overall weak degrees of anisotropy (Pj < 2%). The weak magnetic fabrics reflect the destructive interference between the magnetite fabric and the fabric of hematite and iron hydroxides. Later, pulses of magma are less oxidized, which indicates that the alteration was caused by volatile release from magma that intruded below already emplaced magma. Our results demonstrate that rock magnetic data provide a novel approach to detecting magma pulse interactions and associated alteration in plutons, offering insights into magma body dynamics.

A model for the origin, ascent, and eruption of the lunar A17 orange glass magma has been constructed using petrological constraints from gas solubility experiments and from analyses of the lunar sample 74220 to better determine the nature and origin of this unique explosive eruption. Three stages of the eruption have been identified. Stage 1 of the eruption model extends from ∼550 km, the A17 orange glass magma source region based on phase equilibria studies, to 50 km depth in the Moon. Stage 2 extends from ∼50 km to 500 m, where a C-O-H-S gas phase formed and grew in volume based on melt inclusion analyses and measurements. The volume of the gas phase at 500 m depth below the surface is calculated to be 7 to 15 vol% of the magma (closed-system) using the minimum and maximum estimates of CO, H2O, and S loss from the melt. In Stage 3, depths shallower than ∼450 m, the rising magma exsolved an additional 800-900 ppm H2O and 300 ppm S, increasing the moles in the gas by a factor of 3 to 4. The closed-system gas phase is calculated to reach ∼70 vol% at ∼130 m depth, enough to fragment the magma and form pyroclastic beads. However, fragmentation (bead formation) is interpreted to have occurred at depths ranging from 600 to 300 m below the lunar surface based on the pressure necessary to explain the C content of the orange glass beads. The gas volume (70%) required to fragment the ascending magma at this depth is a factor of ∼5 greater than the volume determined for closed-system degassing of an orange glass magma at 500 m, strongly implying that the gas was produced by open-system degassing as the magma ascended from greater depths.Formation of the dike carrying the magma up from the ∼550 km deep source is considered to occur by a crack propagation mechanism (Wilson and Head 2003, 2017). The rapid dike-propagation process facilitates gas collection by open-system degassing in the upper part of the dike. This is necessary to achieve the gas volumes required for magma fragmentation at 600 m depths, and the magma-ascent velocities to explain the wide areal distribution of the bead deposit. The explosive nature of the picritic orange glass eruption, and the homogeneity of the bead compositions, are consistent with this gas-assisted eruption scenario, as is the evidence of a Fe-metal forming reduction event during Stage 2 followed by a Stage 3 oxidation event in the ascending magma.

Granitic magma bodies form in the ephemeral part of magma mush systems and are emplaced by a variety of mechanisms in different tectonic settings. This study investigates how granitic magma emplacement processes and tectonomagmatic interactions assert control over the architecture of mush state pluton‐scale magma transport pathways. The 1.45 Ga shallow‐crustal Götemar pluton is a 4.5 km diameter circular pluton that consists of three granite units: a coarse‐grained red granite, a medium‐grained pale to red granite, and fine‐grained pale microgranite sheets. We employed geological mapping supported by Anisotropy of Magnetic Susceptibility (AMS) to examine the magmatic and regional tectonic controls on late‐stage magma transport in the Götemar granitic magma mush system. Multiple parallel arcuate subhorizontal microgranite and medium‐grained granite sheets (from 0.1 to 10s of meters thick) were mapped within the pluton. The arcuate sheets pinch out from the northern part of the pluton toward the SE inferring magma propagation direction. A dominant set of vertical granitic sheets within the granite body strikes NW‐SE. The AMS fabrics are contact‐parallel in the main medium‐grained granite body and indicate inflation. Within the microgranite sheets, the AMS fabrics are parallel to the sheet strike and support a sheet propagation direction to the SE. The Götemar pluton displays a clear link between arcuate (concentric) magma‐transporting sheets and concentric strain‐partitioning related to the intrusion of medium‐grained granite magma. The vertical magma sheet orientations are consistent with an NE‐SW extensional stress field that is associated with the extensional back‐arc stress regime of the contemporary Hallandian Orogen. Plain Language Summary The eruptive products of volcanoes are thought to be stored in pockets of melt in crystal‐dominated magmatic systems called crystal mushes prior to volcanic eruptions. An understanding of where magma is stored and how it is transported in mush systems is important in order to predict the eruptive behavior of the volcanic system. This contribution investigates the magma transport pathways in the Götemar granite in Sweden and its relationship to local magmatic deformation and regional deformation related to the Hallandian mountain building event. We show that magma is transported in vertical sheets parallel to the front of the Hallandian Orogen and laterally in sub‐horizontal arcuate sheets that reflect the circular shape of the granite pluton. Our study highlights the importance of understanding the shape and the formation of the magmatic granite body for deciphering the melt transport in the magma mush system under volcanoes. Key Points Subhorizontal magma transport in a granitic magma mush controlled by magma emplacement structures Vertical magma sheets in granitic magma mush controlled by the regional stress field Magma transported in concentric magma fingers in the circular Götemar granite pluton

The Half Dome Granodiorite, Yosemite National Park, California, is recognized in the field by euhedral, fresh-looking, black hornblende phenocrysts up to 2 cm in length. This variety of granodiorite typifies intermediate-age hornblende-phyric units of Cretaceous nested plutonic suites in the Sierra Nevada batholith. Although only inclusions of feldspar are evident in hand samples, the phenocrysts are riddled with up to 50% inclusions of every major mineral found in the host granodiorite plus metamorphic minerals formed during cooling. Amphibole compositions within single phenocrysts vary from actinolite with less than 1 wt% Al2O3 to magnesiohornblende with over 8 wt%. Elemental zoning within the amphibole is highly irregular on the micrometer scale, showing patches and polygonal zones with dramatically different compositions separated by sharp to gradual transitions. The chemical compositions of entire phenocrysts are equivalent to hornblende plus a small proportion of biotite, suggesting that the non-biotite inclusions are the result of metamorphism of the phenocrysts. Backscattered electron imaging shows evidence of brecciation that may have been the result of volume changes as hornblende was converted to actinolite. Pressure calculations using the Al-in-hornblende barometer show unreasonably wide variations on the micrometer scale that cannot have been produced by temperature or pressure variations during crystallization. These hornblende phenocrysts would thus be unsuitable for geobarometry, and caution must be used to avoid similarly zoned phenocrysts in the application of the Al-in-hornblende geobarometer.