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Abstract: Exhumed eclogitic crust is rare and exposures that preserve both protoliths and altered domains are limited around the world. Nominally anhydrous Neoproterozoic anorthositic granulites exposed on the island of Holsnøy, in the Bergen Arcs in western Norway, preserve different stages of progressive prograde deformation, together with the corresponding fluid‐assisted metamorphism, which record the conversion to eclogite during the Ordovician–Silurian Caledonian Orogeny. Four stages of deformation can be identified: (1) brittle deformation resulting in the formation of fractures and the generation of pseudotachylites in the granulite; (2) development of mesoscale shear zones associated with increased fluid–rock interaction; (3) the complete large‐scale replacement of granulite by hydrous eclogite with blocks of granulite sitting in an eclogitic “matrix”; and (4) the break‐up of completely eclogitized granulite by continued fluid influx, resulting in the formation of coarse‐grained phengite‐dominated mineral assemblages. P–T constraints derived from phase equilibria forward modelling of mineral assemblages of the early and later stages of the conversion to eclogite document burial and partial exhumation path with peak metamorphic conditions of ~21–22 kbar and 670–690°C. The P–T models, in combination with existing T–t constraints, imply that the Lindås Nappe underwent extremely rapid retrogressive pressure change. Fluid infiltration began on the prograde burial path and continued throughout the recorded P–T evolution, implying a fluid source that underwent progressive dehydration during subduction of the granulites. However, in places limited fluid availability on the prograde path resulted in assemblages largely consuming the available fluid, essentially freezing in snapshots of the prograde evolution. These were carried metastably deeper into the mantle with strain and metamorphic recrystallization partitioned into areas where ongoing fluid infiltration was concentrated. [ABSTRACT FROM AUTHOR]

In situ LA- ICP- MS U-Pb monazite geochronology from the Boothby Hills in the Aileron Province, central Australia, indicates that the region records more than 80 Ma of high- T, low- P ( HTLP) anatectic conditions during the Early Mesoproterozoic. Monazite ages from granulite facies rocks and leucosomes span the interval 1576-1542 Ma. Pegmatites that overprint the regional gneissic fabric and are interpreted to record the last vestiges of melt crystallization give ages between 1523 and 1513 Ma. Calculated P-T pseudosections suggest peak metamorphic conditions in excess of 850 °C at 0.65-0.75 GPa. The retrograde evolution was characterized by a P-T path that involved minor decompression and then cooling, culminating with the development of andalusite. Integration of the geochronological data set with the inferred P-T path trajectory suggests that suprasolidus cooling must have been slow, in the order of 2.5-4 °C Ma−1. In addition, the retrograde P-T path trajectory suggests that HTLP conditions were generated within crust of relatively normal thickness. Despite the long duration over which anatectic conditions occurred, there is no evidence for external magmatic inputs or evidence that HTLP conditions were associated with long-lived extension. Instead, it seems probable that the long-lived HTLP metamorphism was driven to a significant extent by long-lived conductive heating provided by high crustal heat production in voluminous pre-metamorphic granitic rocks. [ABSTRACT FROM AUTHOR]

Activity-composition ( a-x) models have been generated for zirconium-bearing haplogranitic silicate melt and garnet from experimental data on zircon dissolution and natural rock data, respectively. Additionally including the recently proposed a-x model for Zr-bearing rutile [Tomkins et al., Journal of Metamorphic Geology (2007) 401], calculated phase diagrams that explicitly include ZrO in the bulk composition predict the growth and dissolution of zircon at sub- and supra-solidus conditions. This occurs within the context of the evolution of major metamorphic minerals and mineral assemblages in pressure-temperature-composition space for a metapelitic rock composition. The stability of zircon is a function of the bulk ZrO content. Garnet contains insufficient Zr to affect the stability of zircon whereas rutile does contain sufficient Zr that zircon stability can be curtailed in rocks with significant rutile. Silicate melt contains appreciable Zr and zircon abundance varies inversely with melt abundance. Thermometers based on the Zr-content of rutile (and potentially garnet) can be graphically portrayed as compositional contours in mineral assemblage fields on the phase diagrams, thereby potentially adding to the utilization of such thermometers. The ability to calculate phase diagrams explicitly including Zr is a major step towards more systematically linking zircon growth - and zircon geochronology - and accessory phase thermometry in a readily adaptable way to the metamorphic evolution of major silicate minerals in a wide range of rocks. [ABSTRACT FROM AUTHOR]

In situ LA-ICP-MS monazite geochronology from a garnet-bearing diatexite within the Moine Supergroup (Glenfinnan Group) NW Scotland records three temporally distinct metamorphic events within a single garnet porphyroblast. The initial growth of garnet occurred in the interval c. 825–780 Ma, as recorded by monazite inclusions located in the garnet core. Modelled P–T conditions based on the preserved garnet core composition indicate an initially comparatively high geothermal gradient regime and peak conditions of ∼650 °C and 7 kbar. Monazite within a compositionally distinct second shell of garnet has an age of 724 ± 6 Ma. This is indistinguishable from a SIMS age of 725 ± 4 Ma obtained from metamorphic zircon in the sample, which is interpreted to record the timing of migmatization. This second stage of garnet growth occurred on a P–T path from ∼6 kbar and 650 °C rising to ∼9 kbar and 700 °C, with the peak conditions associated with partial melting. A third garnet zone which forms the rim contains monazite with an age of 464 ± 3 Ma. Monazite in the surrounding matrix has an age of 462 ± 2 Ma. This corresponds well with a U–Pb SIMS zircon age of 463 ± 4 Ma obtained from a deformed pegmatite that was emplaced during widespread folding and reworking of the migmatite fabric. The P–T conditions associated with the final phase of garnet growth were ∼7 kbar and 650 °C. The monazite ages coupled with the phase relations modelled from this multistage garnet indicate that it records two Neoproterozoic tectonothermal events as well as the widespread Ordovician Grampian event associated with Caledonian orogenesis. Thus, this single garnet records much of the Neoproterozoic to Ordovician thermal history in NW Scotland, and highlights the long history of porphyroblast growth that can be revealed by in situ isotopic dating and associated P–T modelling. This approach has the potential to reveal much of the thermal architecture of Neoproterozoic events within the Moine Supergroup, despite intense Caledonian reworking, if suitable textural and mineralogical relationships can be indentified elsewhere. [ABSTRACT FROM AUTHOR]

Mineral equilibria modelling and electron microprobe chemical dating of monazite in granulite facies metapelitic assemblages from the MacRobertson Land coastline, Rayner Complex, east Antarctica, are consistent with an ‘anticlockwise’ Neoproterozoic P–T–t path. Metamorphism occurred at c. 990–970 Ma, achieving peak conditions of 850 °C and 5.6–6.2 kbar at Cape Bruce, and 900 °C and 5.4–6.2 kbar at the Forbes Glacier ∼50 km to the east. These peak metamorphic conditions preceded the emplacement of regionally extensive syntectonic charnockite. High temperature conditions are likely to have been sustained for 80 Myr by lithospheric thinning and repeated pluton emplacement; advection was accompanied by crustal thickening to maximum pressures of 6–7 kbar, followed by near-isobaric cooling. This P–T–t path is distinct from that of rocks in adjacent Kemp Land, ∼50 km to the west, where a ‘clockwise’ P–T–t path from higher- P conditions at c. 940 Ma may reflect the response of a cratonic margin displaced from the main magma flux. In this scenario, crustal shortening was initially accommodated in younger, fertile crust (MacRobertson Land) involving metasediments and felsic plutons with the transfer of strain to adjacent older crust (Kemp Land) subsequent to charnockite emplacement. [ABSTRACT FROM AUTHOR]

Silica-undersaturated, sapphirine-bearing granulites occur in a large number of localities worldwide. Such rocks have historically been under-utilized for estimatingP– Tevolution histories because of limited experimental work, and a consequent poor understanding of the topology andP– Tlocation of silica-undersaturated mineral equilibria. Here, a calculatedP– Tprojection for sapphirine-bearing, silica-undersaturated metapelitic rock compositions is constructed using THERMOCALC for the FeO-MgO-Al2O3-SiO2 (FMAS) and KFMASH (+K2O + H2O) chemical systems, allowing quantitative analysis of silica-undersaturated mineral assemblages. This study builds on that for KFMASH sapphirine + quartz equilibria [Kelseyet al. (2004)Journal of Metamorphic Geology, vol. 22, pp. 559–578]. FMAS equilibria are significantly displaced inP– Tspace from silicate melt-bearing KFMASH equilibria. The large number of univariant silica-undersaturated KFMASH equilibria result in aP– Tprojection that is topologically more complex than could be established on the basis of experiments and/or natural assemblages. Coexisting sapphirine and silicate melt (with or without corundum) occur down toc.900 °C in KFMASH, some 100 °C lower than in silica-saturated compositions, and from pressures ofc.≤1 to≥12 kbar. Mineral compositions and composition ranges for the calculated phases are consistent with natural examples. Bulk silica has a significant effect on the stability of sapphirine-bearing assemblages at a givenP– T, resulting in a wide variety of possible granulite facies assemblages in silica-undersaturated metapelites. Calculated pseudosections are able to reproduce many naturally occurring silica-undersaturated assemblages, either within a single assemblage field or as the product of aP– Ttrajectory crossing several fields. With an understanding of the importance of bulk composition on sapphirine stability and textural development, silica-undersaturated assemblages may be utilized in a quantitative manner in the detailed metamorphic investigation of high-grade terranes. [ABSTRACT FROM AUTHOR]

Sapphirine, coexisting with quartz, is an indicator mineral for ultrahigh-temperature metamorphism in aluminous rock compositions. Here a new activity-composition model for sapphirine is combined with the internally consistent thermodynamic dataset used by THERMOCALC, for calculations primarily in K2O-FeO-MgO-Al2O3-SiO2-H2O (KFMASH). A discrepancy between published experimentally derived FMAS grids and our calculations is understood with reference to H2O. Published FMAS grids effectively represent constant aH2O sections, thereby limiting their detailed use for the interpretation of mineral reaction textures in compositions with differing H2O. For the calculated KFMASH univariant reaction grid, sapphirine + quartz assemblages occur at P–T in excess of 6–7 kbar and 1005 °C. Sapphirine compositions and composition ranges are consistent with natural examples. However, as many univariant equilibria are typically not ‘seen’ by a specific bulk composition, the univariant reaction grid may reveal little about the detailed topology of multi-variant equilibria, and therefore is of limited use for interpreting the P–T evolution of mineral assemblages and reaction sequences. Calculated pseudosections, which quantify bulk composition and multi-variant equilibria, predict experimentally determined KFMASH mineral assemblages with consistent topology, and also indicate that sapphirine stabilizes at increasingly higher pressure and temperature as XMg increases. Although coexisting sapphirine and quartz can occur in relatively iron-rich rocks if the bulk chemistry is sufficiently aluminous, the P–T window of stability shrinks with decreasing XMg. An array of mineral assemblages and mineral reaction sequences from natural sapphirine + quartz and other rocks from Enderby Land, Antarctica, are reproducible with calculated pseudosections. That consistent phase diagram calculations involving sapphirine can be performed allows for a more thorough assessment of the metamorphic evolution of high-temperature granulite facies terranes than was previously possible. The establishment of a a-x model for sapphirine provides the basis for expansion to larger, more geologically realistic chemical systems (e.g. involving Fe3+). [ABSTRACT FROM AUTHOR]

An enzyme immunoassay (EIA) was developed in which nuclear extracts were bound to the wells of polystyrene microtiter plates. The presence of various antigens in the extracts could be detected using antiserum raised against HeLa cell nucleoli. Normal human cell extracts, coupled to Sepharose as a solid phase absorbent, were used to remove antibodies directed against antigens present in normal cells, The resulting purified antibodies produced a linear EIA absorbance in the range of 100-500 ng tumor extract, but little EIA absorbance with nuclear extracts from human placenta and liver.

Fifteen monoclonal antibodies (MAbs) raised against human sperm cells were evaluated for reactions against human sperm by indirect immunofluorescence, immunocytochemistry, agglutination, complement-dependent immobilization, cervical mucus penetration, and hamster egg penetration assays. The MAbs were analyzed for specificity by immunofluorescent reactions with peripheral blood lymphocytes and sperm and classified into three main groups based on regional staining, ie, acrosome, plasma membrane, or tail. One MAb (218) bound to the sperm neck. Three MAbs, (80, 85, and HS-126) were found to react with lymphocytes. Three of five acrosome-reactive MAbs (11, 63, 106), two of five tail-staining MAbs (97, HS-30), and the neck reactor (218) showed significant to highly significant inhibition of sperm penetration of eggs but without significant effects on sperm agglutination, immobilization, or the mucus penetration assay. The three non-specific MAbs gave strong plasma membrane reactions in the agglutination and immobilization assays and also caused highly significant inhibition of sperm penetration of both cervical mucus and zona-free ova. Preliminary analysis of the complementary antigens suggested that epitopes reacting with MAbs 33 (acrosome) and 85 (plasma membrane) were carbohydrate chains on glycoproteins. Three of five MAbs recognizing tail antigen, the neck-staining MAb, and the non-specific MAb (HS-126) appeared to be reactive against glycolipid moieties. Seven of the 12 specific MAbs also reacted in indirect immunofluorescence with mouse and rabbit sperm in patterns similar to those observed with human sperm.