Growth and Characterisation of Layered (BA)2CsAgBiBr7 Double Perovskite Single Crystals for Application in Radiation Sensing

A recent publication on single crystals of two-dimensional, layered organic–inorganic (BA)2CsAgBiBr7 double perovskite (BA+ = CH3CH23NH3+) suggested the great potential of this semiconductor material in the detection of X-ray radiation. Our powder XRD measurement confirms the crystallinity and purity of all samples that crystallise in the monoclinic space group P21/m, while the single crystal XRD measurements reveal the dominant {001} lattice planes. The structure–property relationship is reflected in the lower resistivity values determined from the van der Pauw measurements (1.65–9.16 × 1010 Ωcm) compared to those determined from the IV measurements (4.19 × 1011–2.67 × 1012 Ωcm). The density of trap states and charge-carrier mobilities, which are determined from the IV measurements, are 1.12–1.76 × 1011 cm–3 and 10−5–10−4 cm2V–1s–1, respectively. The X-ray photoresponse measurements indicate that the (BA)2CsAgBiBr7 samples synthesised in this study satisfy the requirements for radiation sensors. Further advances in crystal growth are required to reduce the density of defects and improve the performance of single crystals

Use of in situ Hf-isotope analyses of zircon to interpret granitoid magma genesis

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Carboniferous and Permian granites of the northern Tasman orogenic belt, Queensland, Australia : insights into petrogenesis and crustal evolution from an in situ zircon study

In situ U-Pb dating and Lu-Hf systematics of zircon in granites of the Hodgkinson Province in the northern Tasman orogenic belt, Queensland, Australia, reveal input of isotopically more evolved crustal magmas and larger ranges in ¹⁷⁶Hf/¹⁷⁷Hf in the Carboniferous I-type granites (0. 28219-0. 28269; weighted average ~0. 28245) than in the Permian S-type granites (0. 28249-0. 28280; weighted average ~0. 28262) and Permian I-type granites (0. 28253-0. 28274; weighted average ~0. 28260). The wide range in the Hf-isotope compositions of zircons in the Carboniferous and Permian granites can be explained by remelting of a heterogeneous Mesoproterozoic crustal source, whereas a narrow range reflects the subsequent dissolution of inherited grains/cores and magma homogenisation before zircon crystallisation. Alternatively, mixing between the most radiogenic and unradiogenic magmas can produce the isotopic variation seen in other Carboniferous granites. Remelting of Neoproterozoic average crust or mafic younger crust can produce the more radiogenic Hf-isotope compositions of zircons in the Permian S-type granites. An overlap between the Hf-isotope signatures of the Carboniferous I-type granites in the southwestern Hodgkinson Province and the northeastern Australian craton (0. 28211-0. 28254) and evidence for major magmatic events at 1,585-1,545 and 345-300 Ma imply that the southwestern province is underlain by cratonic crust, which wedges out towards the northeast. The more radiogenic Hf-isotope signature of the Permian granites and a lack of evidence for these major magmatic events in the southeastern and central Hodgkinson Province imply that these parts are characterised by different crustal sources and crustal evolution histories.23 page(s

Lithospheric mantle evolution beneath northeast Australia

New in situ analyses of Re-Os systematics in single grains of sulfides in Cainozoic basalt-borne spinel lherzolite xenoliths from the Chudleigh Province (Australian craton) and Atherton Province (Tasman Fold Belt) are reported. The sulfide data and previously reported U-Pb and Hf-isotope data for detrital zircons and zircons from granitoids (Murgulov et al., 2007; 2009) show correlations between mantle events and crustal magmatism in northeast Queensland, Australia. About half of the analysed sulfide grains have sub-chondritic 187Os/188Os (0.1130-0.1252) and 187Re/188Os (0.0214-0.2061), suggesting preservation of their isotopic signatures during subsequent infiltration of asthenospheric silicate melts/fluids. Collision and accretion processes have probably initiated a melt-extraction event followed by cratonic lithosphere stabilisation at ~2.2Ga (TMA model age). Metasomatism of the mantle lithosphere most likely involved infiltration of asthenospheric melts/fluids during lithospheric thinning and rifting beneath the Chudleigh Province at ~1.82Ga, 0.81Ga and 0.35Ga (TRD Rhenium-depletion model ages), beneath the Atherton Province at ~1.75Ga and 0.44Ga (TRD), and during suturing at ~1.23Ga (TRD), an event recorded beneath both provinces. In the Georgetown Inlier TRD model ages coincide with episodes of granitoid production and demonstrate a close temporal linkage between events in the cratonic lithospheric mantle and crust. However, such linkages cannot be demonstrated in the Tasman Fold Belt; no ~0.44Ga, 1.23Ga or 1.75Ga granites outcrop in this region, and the shallow part of the subjacent lithospheric mantle (~27km depth) experienced a younger (~0.44Ga) metasomatic event not observed in the deeper lithosphere (~49km depth, ~1.75Ga). The younger event may be associated with the reactivation of ancient lithospheric sutures during mantle upwelling and back-arc rifting. The older events may imply that the edge of the cratonic lithospheric mantle root, metasomatised at ~1.75Ga and 1.23Ga, was rifted during a younger event (~0.44Ga?). Its scattered fragments have been embedded at greater depth within the lithospheric mantle beneath the Atherton Province following collision, accretion and lithosphere suturing.18 page(s

Temporal correlation of magmatic-tectonic events in the lower and upper crust in north-east Australia

Hf model ages yielded by rutiles in a garnet-rich lower-crustal granulite xenolith from the McBride Province and whole-rock Nd and Hf model ages for the plagioclase- and garnet-rich Chudleigh and McBride granulites overlap with the well-defined U-Pb ages for detrital zircons and zircons in granitoids (Murgulov et al. Chem Geol 245:198-218, 2007; Mineral Petrol 95:17-45, 2009), suggesting temporal correlation of magmatic-tectonic events in the lower and upper crust in the north-east Australian craton. Intrusion of basaltic magmas into and below the lower crust beneath the Chudleigh Province around 1.4, 1.7 and 2.3 Ga and beneath the McBride Province around 1.5, 1.7, 2.3 and 2.5 Ga provided heat for remelting and supplied magmas with juvenile mantle isotope signatures to the upper crust. Similar magmas provided enough heat to cause melting in the lower crust beneath the Chudleigh Province around 0.12 and 0.8-0.9 Ga and beneath the McBride Province around 0.42, 0.8-0.9 Ga, 1.1 and 1.3 Ga but were not sufficient to cause significant melting in the upper crust. A wide range in initial ¹⁷⁶Hf/¹⁷⁷Hf values and a ~1.55 Ga Hf model age yielded by rutiles in the McBride granulite provide a link to the genesis of ~420 Ma granitoids. The data for a plagioclase-rich granulite from the Atherton Province are similar to those for the Chudleigh and McBride granulites. However, additional samples are required to test whether the lower crust of the Tasman orogenic belt is lithologically and isotopically similar to the lower crust of the craton.19 page(s

Temporal and genetic relationships between the Kidston gold-bearing Breccia Pipe and the Lochaber Ring Dyke Complex, North Queensland, Australia : insights from in situ U–Pb and Hf-isotope analysis of zircon

An existing model for the temporal and genetic relationships between the Kidston gold-bearing Breccia Pipe and the nearby Lochaber Ring Dyke Complex has been evaluated using in situ U–Pb and Hf-isotope analyses of zircon grains. The Oak River Granodiorite, the host rock to the Kidston Breccia Pipe, has 1,551 ± 6 Ma old zircon cores overgrown by 417.7 ± 2.2 Ma rims. The Black Cap Diorite and Lochaber Granite within the Lochaber Ring Dyke Complex have crystallisation ages of 350.7 ± 1.3 and 337.9 ± 2.6 Ma respectively. The gold-rich Median Dyke within the Kidston Breccia Pipe has a crystallisation age of 335.7 ± 4.2 Ma, and thus is temporally related to the Lochaber Granite. However, zircon grains from the Median Dyke have less radiogenic Hf-isotope compositions (ɛ Hf from −7.8 to −15.8) than those from the Black Cap Diorite ɛHf = 0.4 to −7.2) and the Lochaber Granite (ɛ Hf = −1.0 to −7.5), but within the range defined by zircons from the Oak River Granodiorite ɛ Hf  = −8.0 to −29.2). The Hf-isotope data thus rule out the proposed fractional crystallisation relationship between the Kidston gold-bearing rocks and the Lochaber Ring Dyke Complex. The Kidston Median Dyke may have been produced by mixing between Lochaber Granite magmas and magmas derived by remelting of the Oak River Granodiorite, which was itself derived from Proterozoic crust. There is no evidence for a juvenile component in the Lochaber Ring Dyke Complex or the Median Dyke. The gold enrichment in the Kidston rocks thus may reflect the multi-stage reworking of the Proterozoic crust, which ultimately produced the Carboniferous felsic magmas.29 page(s

Magma sources and gold mineralisation in the Mount Leyshon and Tuckers igneous complexes, Queensland, Australia: U-Pb and Hf isotope evidence

In situ LAM-ICPMS U-Pb, Hf-isotope and trace-element analyses of zircon have been used to evaluate the relative contributions of juvenile mantle and crustal sources to the intrusive rocks of the mafic to intermediate, gold-poor Tuckers Igneous Complex (TIC), and the spatially and temporally related, felsic Mount Leyshon Igneous Complex (MLIC), which hosts a gold-rich porphyry system. The TIC intrusions range in age from 304.2 ± 9.1 Ma to 288.5 ± 6.4 Ma, and the MLIC intrusions from 291.0 ± 4.8 Ma to 288 ± 6 Ma. Cross-cutting relationships define the intrusion sequence from oldest to youngest; Diorite, Monzodiorite, Mafic Granodiorite and Biotite Microgranite within the TIC; Early Dyke, Southern Porphyry and Late Dyke within the MLIC. Zircons from the earliest rock type within each complex have a wide range in e{open}Hf (5.2 to 14.8 for the TIC Diorite, 2.0 to 12.4 for the MLIC Early Dykes) suggesting the mixing of juvenile and crustal magmas. This interpretation is supported by trace-element data that show the presence of two distinct zircon populations in the MLIC Early Dyke. The later intrusive rocks have narrower ranges in e{open}Hf (typically < 4 e{open}Hf units) and trace-element patterns of zircon. This homogeneity suggests derivation from magmas produced by further mixing and fractional crystallisation of the TIC Diorite and the MLIC Early Dyke magmas respectively. A greater crustal contribution to the gold-rich MLIC is inferred from the range of median e{open}Hf (3.2 to 4.5 for the MLIC, 5.4 to 8.7 for the TIC). We suggest that the MLIC was derived by melting of more felsic crustal rocks, and with less input from juvenile mantle, then the TIC; it was not derived by fractional crystallisation of an intermediate to mafic TIC-like magma. Modelling of Hf isotope data yields a mean model age of 1040 ± 10 Ma (at 176Lu/177Hf = 0.015) for the crustal component in both complexes. Gold was precipitated in the MLIC Breccia during the emplacement of the Late Dykes. The isotopically homogenous nature of the Late Dykes suggests that no additional juvenile-mantle input was involved at the mineralisation stage. This supports a model in which gold and other metals were indigenous to the Late Dykes magma and were concentrated by magma differentiation and fluid-evolution processes.27 page(s

Crustal evolution in the Georgetown Inlier, North Queensland, Australia : a detrital zircon grain study

The use of in situ Hf-isotope analysis of zircon allows a more detailed evaluation of magma-generation processes than the analysis of whole-rock isotopic systems, and is a powerful tool for studying crustal evolution. Detrital zircon grains have been analysed by in situ LAM-ICPMS and LAM-MC-ICPMS for U-Pb ages, trace element patterns and Hf-isotope composition to evaluate patterns of magma genesis and crustal evolution in the central part of the Precambrian Georgetown Inlier, North Queensland, Australia. Archean zircons and low ∊Hf in Proterozoic and Phanerozoic magmatic zircons provide direct evidence for the existence of Archean crustal components in the Georgetown Inlier, although the surface geology is dominated by Mesoproterozoic basement rocks and Palaeozoic granitoids. Crustal evolution in the Georgetown Inlier has involved at least three stages of heating and granitoid magmatism, possibly associated with basaltic magma underplating and/or overplating (1545–1585 Ma, 420 Ma and 340 Ma). In general, granitoids with high ∊Hf are typical of the Percyvale area, closest to the Phanerozoic Tasman Fold Belt, and may reflect thinner and younger crust. Granitoids with less radiogenic Hf-isotope compositions are typical of the Einasleigh and Mount Surprise areas in the central part of the Inlier, and may reflect the presence of older and thicker crust. The most significant juvenile additions to the crust after Archean time occurred in the Einasleigh and Mount Surprise areas during Mesoproterozoic time and in the Percyvale area during Carboniferous time. In the Mount Surprise area, resorbed zircon cores of Mesoproterozoic age are overgrown by magmatic rims of Siluro–Devonian age. Similarities in the Hf-isotope composition of core-rim pairs suggest that the large range in ∊Hf observed in zircons from Siluro–Devonian granitoids reflects remelting of a heterogeneous 1545–1585 Ma old crust, rather than mixing between juvenile and crustal sources. Crustal remelting has been the main process responsible for the production of granitoid magmas in the Georgetown Inlier. However, minor addition of mantle-derived material may have occurred during both Mesoproterozoic and Carboniferous time. Similarities and differences in the crustal evolution of the Mt Isa, Broken Hill and Georgetown blocks suggest that the Proterozoic history of the Australian continental margin involved the accretion and subsequent dispersal of individual, originally Archean, microcontinents.21 page(s