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High Heat Producing Volcano Plutonic Rocks of the Siner Area, Malani Igneous Suite, Western Rajasthan, India

High Heat Producing Volcano Plutonic Rocks of the Siner Area, Malani Igneous Suite, Western Rajasthan, India

The average total heat generation value of the felsic volcanic (21 HGU) and plutonic rocks (30 HGU) of the study area are much higher than the average value of 3.8 HGU for the continental crust. These volcano-plutonic rocks of the Siner area also also have higher values than the average value of 14.21 HGU obtained from the Kun- dal volcano-plutonic rocks in the MIS [10] and 8.3 HGU from the Peninsular India [21]. Volcanic and plutonic rocks of the Siner area of MIS shows higher concentra- tion of U and Th as compared to A-type granite and rhy- olite of the Northwestern Ontario [22] and A-type rhyo- lite of the St. Francois Mountains, Missouri [23] (Figure 3(c)). The Siner granite samples have the average highest
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Petrology of the Plutonic Rocks at the XIV Iron Oxide Prospect, Bafq Mining District, Central Iran

Petrology of the Plutonic Rocks at the XIV Iron Oxide Prospect, Bafq Mining District, Central Iran

ing cores, the main orebody (northern zone) is continued down to 300 m below surface. The magnetite consists of 62% iron and is phosphorus-poor. The northern ore zone mainly occurs in an aplite dome (caused by late differentiation of granite and called “leuco-metasomatite” in mining terminology) and is composed of the massive magne- tite and hematite ore bodies together with actinolite, all of which are located in the northern and southern parts of the area. The origin of the Bafq district deposits has been the subject of longstanding debate and remains controversial. Also, the ΧІV iron- prospect has received little attention so far. This paper presents the outcome of the pre- liminary petrological investigations on the plutonic rocks of the prospect which partly hosts the mineralization. In this regard, the different rock types of the so called Zarigan granite at the prospect have been studied using petrographic and geochemical investi- gations and have been interpreted accordingly the tectonic setting.
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Lithostratigraphy and Lithochemistry of
Ordovician volcano plutonic rocks in the
Blayney area, central Molong Belt, NSW

Lithostratigraphy and Lithochemistry of Ordovician volcano plutonic rocks in the Blayney area, central Molong Belt, NSW

• Figure 4.5 Simplified stratigraphic logs for the key Ordovician units, showing the lava-dominated facies association of the BLV and the limestone facies association withm the BYV centr[r]

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Lithostratigraphy and Lithochemistry of
Ordovician volcano plutonic rocks in the
Blayney area, central Molong Belt, NSW

Lithostratigraphy and Lithochemistry of Ordovician volcano plutonic rocks in the Blayney area, central Molong Belt, NSW

suites and major Au-Cu mineralisation at many circum-Pacific deposits is the result of complex interactions between tectonic and magmatic processes, and also the physicochemical behaviou[r]

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Plutonic rocks of the Median Batholith in southwest Fiordland, New Zealand: field relations, geochemistry, and correlation

Plutonic rocks of the Median Batholith in southwest Fiordland, New Zealand: field relations, geochemistry, and correlation

Massive to weakly foliated, medium to coarse grained white granodiorite, and granite with minor tonalite, forms c. 99% of the big, Widgeon and Jeanie Plutons, Staircase Tonalite, and related dike swarms (Fig. 3). K-feldspar-rich alkali feldspar granite and syenite form a minor part of the big Pluton (P73131). equigranular textures dominate each unit, with K-feldspar megacrystic textures largely restricted to some of the easternmost parts of the big Pluton. Deep red-brown biotite is the dominant mafic mineral in all four  plutons and related dike swarms (P73489, 73486). in the easternmost 20% of the big Pluton, biotite has a darker brown colour. Muscovite and garnet are common accessory minerals. Dark brown biotite in the easternmost part of the big Pluton and some samples of the Widgeon Pluton can be accompanied by accessory titanite, allanite, and magmatic epidote rather than garnet and/or muscovite. Rare samples along this mineralogical boundary within the big Pluton contain minerals from both sub-assemblages (e.g., P70778, garnet-muscovite-titanite; P70798, muscovite-epidote). However, no clear sharp intrusive contact or marked change in texture or geochemistry coincides with these mineralogical changes in the big Pluton, implying that rocks with both assemblages form part of a single, mineralogically zoned body rather than two separate intrusions. Where titanite is present in trace amounts in the western part of the big Pluton and the Widgeon Pluton, it is restricted to the most biotite-rich samples. Coarse apatite and zircon are present throughout all four intrusions. The low magnetic susceptibility of big Pluton samples (Table 2) suggests that the opaque oxide is ilmenite.
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Rb-Sr GEOCHRONOLOGY OF PEGMATITES, PLUTONIC ROCKS AND A HORNFELS IN THE REGION SOUTH-WEST OF ARAK, IRAN

Rb-Sr GEOCHRONOLOGY OF PEGMATITES, PLUTONIC ROCKS AND A HORNFELS IN THE REGION SOUTH-WEST OF ARAK, IRAN

Prior to this study, the Borujerd complex and the Astaneh intrusion were considered to have formed during one main phase of intrusive activity, during the late Cretaceous [10]. However, these intrusive rocks differ in morphology, structure and mineralogy, and exhibit various degrees of alterations [8]. These differences could reflect emplacement at different times.

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The Heemskirk granite massif, Western Tasmania : a study of chemical variability within plutonic rocks

The Heemskirk granite massif, Western Tasmania : a study of chemical variability within plutonic rocks

Figure 3 The stratigraphical scheme of the section across the Heemskirkgranite massif White granite: W1 contaminated porphyritic granite W2 medium to fine-grained granite W3 coarse-grain[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture·infilling and other secondary minerals, As an analogue for the behaviour o'f t[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture-infilling and other secondary minerals, As an analogue for the behaviour of th[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

8.5 Conclusions The leach testing in deionised water of the Coles Bay Granite, Roxby Downs Granite and the Kambalda Granodiorite with Synroc doped with the mixed fission products under s[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Chapter 8: Simulation of Repository Processes II: The Interaction of Granite and Synroc doped with Mixed Fission Products 8.1 Introduction - Previous Work 8.2 Mixed Fission Products.. 8.[r]

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Index Catalog // Carolina Digital Repository

Index Catalog // Carolina Digital Repository

titanite and groundmass from this study exhibit negative europium anomalies. Eu/Eu*of titanite is expected to decrease with increased fractionation and incompatible element enrichment of the melt. Figure 15 shows this trend, plotted as Eu/Eu* versus Yb concentration in titanite. In general, volcanic titanite crystals with larger negative Eu anomalies have higher concentrations of other REEs (in particular the HREEs), suggesting crystallization from a more fractionated melt. Conversely, there is no slope between Eu/Eu* and the REE content of plutonic titanite, despite differences in the formation of the Mount Princeton Batholith and Sierra Nevada Batholith titanite. This is likely due to the competition between titanite and other REE-bearing phases in plutonic rocks depleting the REEs in the melt phase. If plutonic titanite crystallized early from a high melt-fraction system as opposed to near-solidus conditions, a trend similar to that displayed by the volcanic titanite is
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2017_Bullins.pdf

2017_Bullins.pdf

The Southern Rocky Mountain volcanic field provides an opportunity to discern the field relations between intrusive and extrusive rocks because coeval plutonic and volcanic rocks are exposed and within close proximity to one another. Zircon U-Pb geochronologic data (Tappa et al., 2011; Mills and Coleman, 2013) indicate that, in two locations (the Latir volcanic field and Mount Princeton), plutonic rocks that are age- equivalent to tuffs are limited to small (meter-scale) dikes: large, kilometer-scale plutons are either demonstrably older or younger than the erupted rocks.
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Petrology, Geochemistry and Tectonomagmatic Evolution of Hezar Igneous Complex (Rayen- South of Kerman- Iran): the First Description of an Arc Remnant of the Neotethyan Subduction Zone

Petrology, Geochemistry and Tectonomagmatic Evolution of Hezar Igneous Complex (Rayen- South of Kerman- Iran): the First Description of an Arc Remnant of the Neotethyan Subduction Zone

The Hezar Igneous Complex (HIC) in the south-eastern part of Urumieh-Dokhtar magmatic arc, is the most prominent magmatic feature in the Kerman Porphyry Copper Belt, that understanding magmatic evolution of which may shed light on the tectonomagmatic development of this less-studied part of an important magmatic arc in the Neotethys realm. The HIC has been developed in the the intersection of the NS- striking Sabzevaran fault and the NW-SE striking Rafsanjan-Rayen fault. It is indicated that the possible place of the conduit and vent is in Jalas Mountain which has been splitted later by the Sabzevaran fault into Minor and Major Jalas. The current summit had been constructed by ascending magma chamber under the HIC that constitutes the Kamali Mountain at the south of the summit. Some plutonic rocks of the HIC are exposed at Kamali Mountain. The subalkaline rocks of this complex mainly are composed of different pyroclastic and lava flow rocks, acidic to basic in composition, showing the evidences of fractional crystallization and mineral segregation. Sequential explosive and effusive eruptions with Strombolian to Vulcanian types are evident in the successive volcanic layers. The compositional trend shows the melting of spinel lherzolite, not garnet lherzolite. The subduction-related mechanism of the magma genesis has been indicated by IAB nature of the magma formation in geochemical diagrams.
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Testing competing caldera models using U_Pb geochronology : intrusive history of the Questa caldera, Latir Volcanic Field, New Mexico, USA

Testing competing caldera models using U_Pb geochronology : intrusive history of the Questa caldera, Latir Volcanic Field, New Mexico, USA

However it is possible to dilute the effect of shallow fractionation in the chemistry of sub-caldera plutonic rocks if these rocks are generated in systems with very high intrusive:extrusive rock ratios (Lipman, 2007). The inferred batholith at Questa is approximately equal in size to the ignimbrite (500 km 3 ) and therefore yields a ratio of approximately 1:1 (Cordell et al., 1985). This ratio is significantly less than the most prominently cited 10:1 ratio (Smith, 1979), but compares more favorably to lower ratios (2-3:1) proposed in recent work (White et al., 2006). These low intrusive:extrusive ratios are not conducive to hiding the geochemical signature of melt extraction in plutonic rocks. In fact, as the ratio converges on low estimates (e.g. 1:1 Latir ratio), the problem is exacerbated. Thus it appears that the intrusive:extrusive rock ratio of the Latir field is not sufficiently high enough to dilute the effect of fractionation.
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Geochemistry and U_Pb zircon geochronology of the Virgin Islands batholith, British Virgin Islands

Geochemistry and U_Pb zircon geochronology of the Virgin Islands batholith, British Virgin Islands

Modern whole-rock Pb isotope values of Cretaceous, Eocene, and Oligocene calc- alkaline rocks of Puerto Rico and the Virgin Islands overlap with Plutonic rocks of the Virgin Islands batholith; however, values from the batholith extend to more isotopically enriched Pb isotope values overlapping with data from the northern Lesser Antilles volcanic rocks (Fig. 9). The Cretaceous Water Island Formation is significantly less isotopically enriched than the Virgin Islands batholith, overlapping the field of MORB values. The central and southern Lesser Antilles extends to Pb isotope compositions that are greatly enriched relative to those of the Virgin Islands batholith. The Pb isotopic character of Lesser Antilles lavas show a decrease in Pb isotopic values from south to north that has been interpreted to reflect a decrease in the amount of subducted terrestrial-derived sediments and arc crust incorporated into the arc magmas (Davidson, 1987; White and Dupré, 1986). Frost et al. (1998) concluded the amount of terrigenous material incorporated into Puerto Rican arc magmas was similar to or slightly greater than the amount incorporated into arc magmas of the northern Lesser Antilles. This conclusion is consistent with Pb isotopic values from the Virgin Islands batholith; however, within the Virgin Islands batholith lead isotopic values of the suites appear to become less enriched with age, most notably between the North Sound and Peter Island suites. This trend mimics that seen in the 87 Sr/ 86 Sr i values and supports the hypothesis
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The geology of Ben Nevis, South west Highlands, Scotland

The geology of Ben Nevis, South west Highlands, Scotland

Plutonic rocks of the Ben Nevis Complex are subdivided into the Fine Quartz Diorite, Sgurr Finnisg-aig Quartz Diorite, Coarse Quartz Diorite, Porphyritic Outer Granite and Inner Granite;[r]

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Economic Geology of the XIV Iron Oxide Prospect, Bafq Mining District, Central Iran: A Preliminary Approach

Economic Geology of the XIV Iron Oxide Prospect, Bafq Mining District, Central Iran: A Preliminary Approach

The alteration assemblages associated with the iron ore deposits are evidence of an im- portant metasomatic component in the ore-forming process, where the alteration mi- neralogy is controlled by the bulk chemistry of rock, the composition of the mineraliz- ing fluids, and P-T conditions of formation. However, alteration at the XIV iron pros- pect shows a general transition from sodic alteration (albite-rich) at deeper levels espe- cially in the plutonic rocks or their adjacent volcanics, to potassic alteration (potassium feldspar + sericite) at intermediate levels (in the plutonic), to sericitic and silicic altera- tion (sericite + quartz) in the uppermost portion of the system. Actinolite (sodic-calcic
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Geothermobarometry of Askaoun Pluton in Ouzellarh Sirwa Promontory (Central Anti Atlas; Morocco)

Geothermobarometry of Askaoun Pluton in Ouzellarh Sirwa Promontory (Central Anti Atlas; Morocco)

ferent Al-in-hornblende thermometric algorithms on data from plutonic rocks, [14] concluded that edenite-richte- rite thermometer is the most reliable calibration. There- fore, we used edenite-richterite thermometer to calculate the temperature of crystallization of the Tifnoute valley plutonic rocks and their MMEs. Equilibration tempera- ture for hornblend-plagioclase assemblage were calcu- lated based on iteration using [13] pressure at various thermometers. The (Table 1) shows the types of ther- mometers applied for estimation of the temperature. From analyzed rocks, the calculated temperatures (edinite- richterite thermometer) are in the range 505˚C to 611˚C for host rocks and 563˚C to 633˚C for MMEs.
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Petrological studies of Devonian rocks in Scotland and cretaceous rocks in Canada

Petrological studies of Devonian rocks in Scotland and cretaceous rocks in Canada

According to the stratigraphical classification set up by Armstrong and Paterson (1970), the sediments described in this thesis lie within the 1525 m thick Garvock Group, towards the top of Lower Old Red Sandstone and are approximately Siegenian in age (Table 1.1). These sediments are composed largely of sandstone formations and represent the southeastern limb of Sidlaw Anticline (Fig. 1.1). The oldest subdivision of the Lower Old Red Sandstone (the Stonehaven Group) lies unconformably on Cambro-Ordovician rocks and is considered to be Infra-Gedinnian (topmost Silurian) in age (Mykura, 1983). On the basis of Rb-Sr dating of lavas (Arbuthnott Group), Thirlwall (1981 and 1983) suggested that a substantial part of the Lr, Old Red Sandstone could be of Silurian age, Westoll (1977), considering the spore content of the youngest subdivision (Strathmore Group), ascribed a middle Emsian age whereas plant remains such as Psilophyton ££inc£ps., JP,. golsi^chmidii. and .Arthrosiignia graclle suggest a late Siegenian date (Mykura, 1983). The Strathmore Group is overlain unconformably by Upper Old Red Sandstone.
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