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Petrographic, whole‐rock geochemical and geochronological analysis of polymictic conglomerate, associated siltstone and greywacke in the Neoarchean Gadag Greenstone Belt in the Western Dharwar Craton, India, provides new insights into sedimentary provenance and tectonic setting. The polymictic conglomerate contains granitic, gneissic, felsic and mafic volcanic, quartzite and banded ferruginous chert clasts within a quartzo‐feldspathic matrix. Framework grains in the siltstone and greywacke are quartz, feldspar with rock fragments, embedded in a chlorite‐dominant matrix. The chemical index of alteration values (~70) and A‐CN‐K plot for the rocks suggest a low‐to‐moderate degree of weathering. Rare earth element (REE) patterns show moderate fractionation (LaN/YbN ~ 12.31) with a weak negative europium anomaly (0.82). Enrichment in transition elements (Ni, Cr, Co, Sc) and depletion in high‐field‐strength elements, as well as relatively low La/Co (0.62), moderate to high Th/Yb (3.06), La/Th (5.16), La/Yb (17.5), and La/Sc (~2.37) ratios, suggest a mixed felsic‐mafic provenance. U–Pb dating of detrital zircon from the conglomerate and greywacke revealed major age peaks at ca. (3.2, 2.9, 2.8, 2.6, 2.5 Ga) and a maximum age of deposition of 2,508 ± 26 Ma, 2,493 ± 20 Ma, respectively. The above data suggest low to moderately weathered proximal sources for both conglomerate and greywacke, indicating that these two rock types were not deposited simultaneously, but rather separately. The association of these conglomerates and greywacke with continental arc‐related volcanics indicates the closing of an arc at the time of sedimentation. Complex provenance consisting of recycled and magmatic arc during basin closure confirm the notion of modern style plate tectonics operating during Neoarchaean. [ABSTRACT FROM AUTHOR]

Clast morphometry and sedimentary facies analysis of polymictic conglomerate of the Hiriyur Formation in the Gadag greenstone Belt, Western Dharwar Craton, India, was conducted to constrain the palaeohydraulic condition, depositional environment, and type of sedimentary basin. The conglomerate grades from clast‐supported to matrix‐supported with siltstone‐sandstone intercalations. Eight lithofacies along with five major lithofacies associations are recognized in the Majjur and Attikatti Domains of the Gadag greenstone Belt. The lithofacies architecture suggests sedimentation commenced with rapid deposition of slope‐derived debris in a proximal high‐energy alluvial fan setting followed by a braided river environment. Clast morphometry and palaeohydraulic data indicate a low palaeoslope (0.000024 m/m), and stream discharge value (1.913 m3/s) calculated from the channel fill conglomerates. Greywacke overlying the conglomerate has been interpreted as turbidites from a continental slope. The accompanying 40‐m‐thick banded iron formation and carbonate rocks also support a marine context. The lack of transitional deposits between river and deep marine settings suggests that the greywacke turbidites sequence is separated from the conglomerate deposits by substantial unconformities. This change in depositional setting could be due to a change in basin subsidence rate, tectonic rejuvenation, or major sea‐level changes. [ABSTRACT FROM AUTHOR]

The Xindian deposit is a medium tonnage (>5 tonnes of Au) quartz vein‐type gold deposit located on the south‐central part of the Liaodong Peninsula, China. A total of 37 auriferous quartz veins are hosted within the Paleoproterozoic metamorphic rocks of the Gaixian Formation and Late Triassic porphyritic biotite granite. Mineral paragenesis indicates that gold mineralization took place in three stages: early milky quartz‐pyrite stage, main gray quartz‐polymetallic sulfide and gold stage, and late quartz‐calcite‐pyrite stage. Silicification and pyritization are spatially and temporally associated with the main mineralization stage. Zircon U–Pb dating from dikes that predate and postdate the mineralization constrain the timing of mineralization to the Early Cretaceous, between 127.2 and 120.9 Ma. High‐precision in‐situ S isotope analyses yielded δ34S values for pyrite, sphalerite and galena of 10.1–11.0‰, 10.3–10.5‰, and 8.6–8.8‰, respectively, indicating that S was derived from the multiple sources. In‐situ Pb isotope analyses resulted in 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb ratios of 38.207–38.634, 15.598–15.668, and 18.027–18.143, respectively, for pyrite and galena, suggesting Pb derivation from a mixture of Gaixian Formation metamorphic rocks and other potential sources. In‐situ LA‐ICP‐MS trace element mapping and spot analyses show that the inner core of the pyrite (Py‐ic) formed early and is generally enriched in Au, As, Co, Ni, Bi, and Te, the outer core of the pyrite (Py‐oc) contains less Co, Ni, As, and Au, but more Cu, Pb, and Zn, whereas the rim of the pyrite (Py‐r) is enriched in Ag, Sn, Sb, Cu, Pb, and Zn. Trace element signatures of pyrite reveal that the mineralizing fluid was initially of magmatic‐hydrothermal origin, and subsequently modified by intensive interaction with the wall rock (Gaixian Formation). Our results consistently demonstrate that the Xindian gold deposit is resulted from fluid–rock interaction between the Early Cretaceous magmatic‐hydrothermal fluids and Gaixian Formation metamorphic wall rocks that enriched the metal budget of the mineralizing fluid. Then the addition of meteoric water significantly changed the physical and chemical conditions of the mineralizing fluid, triggering gold precipitation in the Xindian deposit. The results of our study expand the Early Cretaceous gold metallogenic models in the Liaodong Peninsula, highlighting the importance of the Gaixian Formation for regional gold mineralization. [ABSTRACT FROM AUTHOR]

New Cu isotope data obtained on chalcopyrite from the Black Mountain and the Broken Hill deposits in the medium‐ to high‐grade metamorphic Aggeneys‐Gamsberg ore district (South Africa) require a revision of our understanding of the genesis of metamorphic Broken Hill‐type massive sulphide deposits. Chalcopyrite from both deposits revealed unusually wide ranges in δ65Cu (−2.41 to 2.84‰ NIST 976 standard) in combination with distinctly positive mean values (0.27 and 0.94‰, respectively). This is interpreted to reflect derivation from various silicate and oxide precursor minerals in which Cu occurred in higher oxidation states. Together with the observation of a typical supergene base metal distribution within the deposits and their spatial association with an unconformity only meters above the ore horizon, our new data are best explained by supergene oxidation of originally possibly SEDEX deposits prior to metamorphic sulphide formation, between the Okiepian (1,210–1,180 Ma) and Klondikean (1,040–1,020 Ma) orogenic events. [ABSTRACT FROM AUTHOR]

The Xinfang deposit is a large gold deposit (>20 t of Au) on the southern edge of the Liaodong Peninsula, China. A total of 37 gold‐bearing orebodies are identified along NS‐ and NW‐striking faults and are mainly hosted by the Archean and Neoproterozoic metamorphic rocks. Three stages of hydrothermal mineralization are distinguished, including Stage I of dominant quartz ± pyrite (Py1), Stage II of quartz‐polymetallic sulfide (Py2), and Stage III of quartz‐calcite ± pyrite (Py3). Gold primarily occurs at the Stage II in association with intensive silicification, pyritization, and sericitization. Here, we report on high‐precision in‐situ LA‐MC‐ICP‐MS analyses of S and Pb isotopic compositions of the sulfide minerals and LA‐ICP‐MS analyses of trace element signature of the pyrite from the Xinfang gold deposit. The δ34S values of the sulfides range from 1.3 to 5.3‰, which is consistent with a magmatic origin of S. The sulfides yield 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb ratios of 37.497–37.773, 15.323–15.410, and 17.004–17.229, respectively, which deviate from the values of the wall rocks, suggesting an external Pb source. The in‐situ LA‐ICP‐MS spot analyses of the pyrite reveals that gold occurs in two generations of pyrite (Py2 and Py3) but at low concentrations (≤0.06 ppm for Py2, ≤0.24 ppm for Py3). Visible gold, however, only occurs in the Stage II assemblage as inclusions in pyrite and quartz, and is distributed along the margins or within the fractures of the sulfides. The Py2 shows high Co, Ni, and As concentrations and is depleted in other trace elements typical of a magmatic‐hydrothermal derivation. In contrast, Py3 exhibits low concentrations in most trace elements. Trace element mapping of Py2 revealed correlations between Fe and Co, as well as Ni and As, indicating their couped substitution in the pyrite structure. The available geological, petrographic and geochemical data consistently suggest that the Xinfang gold deposit formed during the Early Cretaceous by hydrothermal fluids of magmatic contribution. [ABSTRACT FROM AUTHOR]

The aim of the present review was to compare state-of-the-art care and future perspectives for the detection and treatment of non-muscle-invasive transitional cell carcinoma ( TCC) of the bladder. We provide a summary of the third expert meeting on 'Optimising the management of non-muscle-invasive bladder cancer, organized by the European Association of Urology Section for Uro- Technology ( ESUT) in collaboration with the Section for Uro- Oncology ( ESOU), including a systematic literature review. The article includes a detailed discussion on the current and future perspectives for TCC, including photodynamic diagnosis, optical coherence tomography, narrow band imaging, the Storz Professional Image Enhancement system, magnification and high definition techniques. We also provide a detailed discussion of future surgical treatment options, including en bloc resection and tumour enucleation. Intensive research has been conducted to improve tumour detection and there are promising future perspectives, that require proven clinical efficacy. En bloc resection of bladder tumours may be advantageous, but is currently considered to be experimental. [ABSTRACT FROM AUTHOR]

OBJECTIVE To evaluate a series of repeat transurethral resections (TURs) of tumour in patients with T1 bladder cancer, usually used to ensure a complete resection and to exclude the possibility muscle-invasive disease. PATIENTS AND METHODS In all, 136 consecutive patients had a second TUR because of a histopathological diagnosis of T1 transitional cell carcinoma (TCC) after their initial TUR. Of the 136 patients, 101 were first presentations and 35 had recurrent tumours. The second TUR was done 4–6 weeks later. The evaluation included the presence of previously undetected residual tumour, changes to histopathological staging/grading, and tumour location. RESULTS In all, 71 patients (52%) had residual disease according to findings from specimens obtained during the second TUR. The staging was: no tumour, 65 (48%); Ta, 11 (8%); T1, 32 (24%); Tis, 15 (11%); and ≥ T2, 13 (10%). Histopathological changes that worsened the prognosis (>T1 and or concomitant Tis) were found in 21% of patients. Residual malignant tissue was found in the same location as the first TUR in 86% of the patients, and at different locations in 14%. Overall, 28 patients (21% of the original 136) had a radical cystectomy as a consequence of the second TUR findings. CONCLUSIONS A routine second TUR should be advised in patients with T1 TCC of the bladder, to achieve a more complete tumour resection and to identify patients who should have a prompt cystectomy. [ABSTRACT FROM AUTHOR]