Platinum-group element geochemistry of the Panjal Traps: constraints on mantle melting and implications for mineral exploration

2021 ◽  
pp. SP518-2020-241
Author(s):  
J. Gregory Shellnutt ◽  
Kwan-Nang Pang ◽  
Liang Qi ◽  
Ghulam M. Bhat
Keyword(s):  
Mineral Exploration ◽  
Volcanic Rocks ◽  
Temperature Behaviour ◽  
Element Geochemistry ◽  
Tiny Amount ◽  
Sulfide Melt ◽  
Platinum Group ◽  
Group 2 ◽  
Different Origins ◽  
Group 1

AbstractForty-two volcanic rocks of the Panjal Traps were analyzed for platinum-group elements (PGE) to investigate magma genesis, high-temperature behaviour, and exploration potential of these elements. The PGE data exhibit substantial variability and show no systematic relation to their low-Ti or high-Ti affinity. Instead, the basalts can be subdivided into PGE-undepleted (group 1) that has ∑PGE > 10 ppb and Cu/Pd < 30000, and PGE-depleted, that consists of a subgroup showing limited (group 2A) or substantial depletion in IPGE relative to Ni (group 2B). The group 1 samples indicate a S-undersaturated history whereas the group 2 samples might have different origins in terms of S-saturation. Fractionation of a tiny amount of sulfide melts (0.075 to 0.1%) from a representative group 1 sample accounts for the chalcophile element patterns observed in the group 2B samples. The relatively high Cu/Pd, unfractionated Ni/Ir, and low PGE abundances observed in the group 2A samples cannot be explained by equilibration of an immiscible sulfide melt alone, and probably requires decomposition of residual sulfides into sulfide melt and a mss in the mantle restite. Our results question the notion that the coexistence of PGE-undepleted and PGE-depleted magmas are prospective in the exploration of magmatic Ni-Cu-(PGE) sulfide mineralization.

XXVIII.—Geological Observations in South-eastern and Central Iceland

1949 ◽  
Vol 61 (3) ◽  
pp. 779-791 ◽  
Author(s):  
F. W. Anderson
Keyword(s):  
Volcanic Rocks ◽  
Glacial Deposits ◽  
South Eastern ◽  
Group 3 ◽  
East And West ◽  
Group 2 ◽  
Basalt Plateau ◽  
Basaltic Lavas ◽  
Group 1

The volcanic rocks of Iceland have been grouped by Tyrrell and Peacock (1928) into:3. The Recent, Post-Glacial and Late Interglacial Eruptives.2. The Early Glacial Breccia or Palagonite Formation.1. The Pre-Glacial Kainozoic Basalt Plateau.Group 1 consists of nearly 10,000 feet of basalts with lignite beds, acid extrusives and acid and basic intrusions. In the east and west of Iceland the old plateau is exposed, but centrally it is down-faulted and covered with more recent tuffs and lavas.Group 2 contains a varied assemblage of deposits comprising tuffs, breccias and lavas, moraines, boulder clays and fluvioglacial sediments (Nielsen and Noe-Nygaard, 1936 a). The lower part of this formation consists of over 2000 feet of basaltic lavas with interbedded glacial and fossiliferous deposits, and the upper part of glacial and fluvio-glacial deposits with doleritic lavas.Group 3 is made up mainly of basaltic lavas but with occasional acid phases. In the ice-covered highlands the volcanoes have continued to produce tuffs and breccias.

scholarly journals Geochronology and Geochemistry of Late Paleozoic Volcanic Rocks and Their Relationship With Iron and Molybdenum Deposits in Xilekuduk Area, Northern Margin of Junggar

2021 ◽  
Vol 9 ◽  
Author(s):  
Xiaofeng Wei ◽  
Hao Wei ◽  
Zhen Liao ◽  
Zhiwei Wang ◽  
Dong Li ◽  
...  
Keyword(s):  
Volcanic Eruption ◽  
Mineral Exploration ◽  
Volcanic Rocks ◽  
Island Arc ◽  
Element Geochemistry ◽  
Northern Margin ◽  
Two Phases ◽  
Basic Volcanic ◽  
Two Stages ◽  
Volcanic Activities

A large number of intermediate basic volcanic rocks and porphyry Cu-Mo deposits as well as volcanic-hosted magnetite deposit have been recently discovered in the Xilekuduk area. However, no reports concerning petrogenesis and age or their relationship with mineralization have been published to date. The purpose of this study was to make up for the absence of previous studies on Devonian volcanic activities in the area and to confirm the relationship between two stages of volcanic activities and mineralization so as to provide important theoretical basis for mineral exploration. Based on research results of zircon U-Pb geochronology and element geochemistry of volcanic rocks in the area, the ages of dacite, andesite, and stomatal andesite are considered as 375.2 ± 2.9 Ma, 386.5 ± 3.0 Ma, and 317.9 ± 2.9 Ma, respectively, corresponding to the Middle Devonian and Late Carboniferous Period. The Devonian volcanic rocks belong to the high-K calc-alkaline series and island arc volcanic rocks, which are enriched in LREE, strongly enriched in large ion lithophile elements Th, Rb, Ba, and K and relatively depleted in high-field strength elements (HFSEs) Nb, Ta, and Ti. The Carboniferous volcanic rocks are enriched in LREE, as well as the large ion lithophile elements Th, Rb, Ba, and K are strongly enriched, while depleted in the HFSEs Nb, Ta, and Ti; moreover, the contents of TiO2 and V are 0.94–0.97% and 178–183×10–6, which are higher than those of island arc basalts. According to mineralogical typomorphic characteristics and geochemical analysis, magnetite mineralization is divided into two phases. The early stratiform magnetite ore MT1 has magmatic characteristics, forming a volcanic rock type magnetite deposit related to Devonian volcanic eruption and sedimentation (375–386 Ma). The magnetite MT2 in the magnetite-quartz vein is considered as hydrothermal genesis, which is a metal mineral in the early metallogenic stage of Carboniferous (317.1 ± 2.9 Ma) volcanic eruption and subvolcanism, and may be related to porphyry molybdenum mineralization. Therefore, the volcanism and Fe-Cu-Mo mineralization in this area is characterized by multistage superimposed mineralization.

Geochemical constraints on magmatic and metallogenic processes: Iskut River Formation, volcanogenic massive sulfide-hosting basalts, NW British Columbia, Canada

2015 ◽  
Vol 52 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Tony Barresi ◽  
JoAnne L. Nelson ◽  
Jaroslav Dostal
Keyword(s):  
British Columbia ◽  
Volcanic Rocks ◽  
Crustal Contamination ◽  
Massive Sulfide ◽  
High Heat ◽  
Volcanogenic Massive Sulfide ◽  
Northern Half ◽  
Vms Deposits ◽  
Group 2 ◽  
Group 1

Volcanic rocks of the Jurassic Iskut River Formation (IRF) in northwestern British Columbia (Canada) host several volcanogenic massive sulfide (VMS) deposits, including the exceptionally high-grade Eskay Creek Ag–Au–Cu–Pb–Zn deposit. The IRF comprises voluminous pillow basalt (>90%), minor rhyolite, and sedimentary rock of late Early to early Middle Jurassic age, filling a series of sub-basins along a 300 by 50 km north-trending belt. Two geochemically distinct types of tholeiitic basalts interfinger; both resemble back-arc basin basalts formed from the melting of asthenospheric and sub-arc mantle sources. Group 2 basalts are more enriched in light rare-earth elements, Ba, K, Sr, Th, and U, and have lower positive εNd values than group 1 basalts (+3.2 to +6.3 versus +6.9 to +8.4, respectively). The compositional differences between group 1 and group 2 basalts are interpreted to result from crustal contamination in group 2. Group 1 basalts are most common in the southern part of the IRF belt where they are closely associated with the Eskay Creek, Bonanza, and Hidden Creek (Anyox) VMS deposits. Group 2 basalts are most abundant in the northern half of the belt and are not associated with exploited mineral deposits. The lack of crustal contamination in group 1 basalts indicates that they formed from rapidly ascending magma in an advanced rift setting and were associated with high heat flow that drove hydrothermal circulation. Group 1 and group 2 basalts are reliably discriminated by Ta/Th <2.5 in the former and >2.5 in the latter. This geochemical criteria can therefore be used as an exploration tool to identify VMS permissive sub-basins and (or) stratigraphy in the IRF.

In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin
Keyword(s):  
Vascular Graft ◽  
Graft Infection ◽  
Vascular Graft Infection ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Prosthetic Vascular Graft Infection ◽  
Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

The influence of continuous local wound infusion on postoperative pain in patients undergoing transfemoral amputation

VASA ◽  
2015 ◽  
Vol 44 (5) ◽  
pp. 381-386 ◽  
Author(s):  
Christian Uhl ◽  
Thomas Betz ◽  
Andrea Rupp ◽  
Markus Steinbauer ◽  
Ingolf Töpel
Keyword(s):  
Pain Management ◽  
Pilot Study ◽  
Local Anaesthetic ◽  
Phantom Pain ◽  
Transfemoral Amputation ◽  
Postoperative Wound ◽  
Stump Pain ◽  
Management Protocol ◽  
Group 2 ◽  
Group 1

Abstract. Summary: Background: This pilot study was set up to examine the effects of a continuous postoperative wound infusion system with a local anaesthetic on perioperative pain and the consumption of analgesics. Patients and methods: We included 42 patients in this prospective observational pilot study. Patients were divided into two groups. One group was treated in accordance with the WHO standard pain management protocol and in addition to that received a continuous local wound infusion treatment (Group 1). Group 2 was treated with analgesics in accordance with the WHO standard pain management protocol, exclusively. Results: The study demonstrated a significantly reduced postoperative VAS score for stump pain in Group 1 for the first 5 days. Furthermore, the intake of opiates was significantly reduced in Group 1 (day 1, Group 1: 42.1 vs. Group 2: 73.5, p = 0.010; day 2, Group 1: 27.7 vs. Group 2: 52.5, p = 0.012; day 3, Group 1: 23.9 vs. Group 2: 53.5, p = 0.002; day 4, Group 1: 15.7 vs. Group 2: 48.3, p = 0.003; day 5, Group 1 13.3 vs. Group 2: 49.9, p = 0.001). There were no significant differences between the two groups, neither in phantom pain intensity at discharge nor postoperative complications and death. Conclusions: Continuous postoperative wound infusion with a local anaesthetic in combination with a standard pain management protocol can reduce both stump pain and opiate intake in patients who have undergone transfemoral amputation. Phantom pain was not significantly affected.

Abnormal Haemostasis and Blood Viscosity in Malignant Hypertension

1984 ◽  
Vol 52 (03) ◽  
pp. 253-255 ◽  
Author(s):  
C Isles ◽  
G D O Lowe ◽  
B M Rankin ◽  
C D Forbes ◽  
N Lucie ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Viscosity ◽  
Renal Damage ◽  
Antithrombin Iii ◽  
Plasma Viscosity ◽  
Malignant Hypertension ◽  
Fibrin Deposition ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.

Total Knee Arthroplasty after Previous Ipsilateral Hip Arthroplasty Showed Lower Clinical Outcomes and Higher Leg Length Discrepancy Perception

2020 ◽  
Author(s):  
Han-Jun Lee ◽  
Seong Hwan Kim ◽  
Nicolas Pujol ◽  
Yong-Beom Park
Keyword(s):  
Clinical Outcomes ◽  
Hip Arthroplasty ◽  
Leg Length ◽  
Function Score ◽  
Patient’S Satisfaction ◽  
Length Discrepancy ◽  
Total Knee ◽  
Group 2 ◽  
Ks Function ◽  
Group 1

AbstractThe purpose of this study is to compare perception of leg length discrepancy (LLD) and clinical results of total knee arthroplasties (TKA) in patients with or without previous ipsilateral hip arthroplasty. Between 2008 and 2015, navigation-assisted TKA was performed in 43 patients with previous hip arthroplasty after hip fracture. After 1:3 propensity score matching was performed, 108 patients of primary navigation-assisted TKA (group 1) and 36 patients with hip arthroplasty (group 2) were included. Knee Society (KS) scores, Western Ontario and McMaster Universities Index (WOMAC) scores, and patients' satisfaction including perception of LLD were evaluated. Radiographic evaluation included mechanical axis, component position, and LLD. Logistic regression analysis was performed to find the factors that affect the clinical outcomes. No significant differences in radiologic and clinical evaluations, except for KS function score, patient's satisfaction and LLD (p< 0.001), were detected between the groups. LLD and its perception were significantly higher in group 2 (1.8 ± 3.4 mm in group 1 and 9.7 ± 4.1 mm in group 2, p = 0.000). Risk factors for the low KS function score were found as LLD (odds ratio [OR]: 1.403, p = 0.008) and previous hip arthroplasty itself (OR: 15.755, p = 0.002), but much higher OR was found in previous hip arthroplasty. Although the outcomes of TKA in patients with ipsilateral hip arthroplasty are comparable to those of primary TKA, LLD was high and patient's satisfaction and functional outcomes were low in patients with previous ipsilateral hip arthroplasty. Care should be taken when considering TKA in patients with previous hip arthroplasty. This is a Level III, case control study.

Clinical and Radiological Changes after use of Alpha-1 Blocker Therapy in Patients of Posterior Urethral Valve with Bladder Neck Hypertrophy

JMS SKIMS ◽  
2009 ◽  
Vol 12 (1) ◽  
pp. 3-7
Author(s):  
Aejaz A Baba ◽  
Bajpai Minu
Keyword(s):  
Bladder Neck ◽  
Posterior Urethral Valve ◽  
Posterior Urethral Valves ◽  
Blocker Therapy ◽  
Urethral Valve ◽  
Novel Method ◽  
Radiological Changes ◽  
Group 2 ◽  
Mean Time ◽  
Group 1

Background: We evaluated the effects of alpha-1 blocker therapy on clinical and radiological abnormalities in patients of posterior urethral valve with bladder neck hypertrophy. Materials and Methods: A total of 74 patients with posterior urethral valves were seen at our department between 2003 and 2007. Out of these 24 had radiological evidence of bladder neck hypertrophy. Those patients with bladder neck hypertrophy who were seen before June 2006 and did not receive alpha-1 blocker (prazocin) therapy after valve ablation were assigned to group 1 (n=10). Group 2 consisted of 14 age matched patients with bladder neck hypertrophy and comparable prognostic factors who received alpha-1 blocker therapy after valve ablation (n=14). Micturating cystourethrography (MCU) was done periodically and a novel method used to calculate bladder neck hypertrophy. Trends in symptoms and radiological changes were evaluated throughout follow-up. Results: Mean patient age at presentation was 3.02±2.68 years in group 1 and 3.12±3.4 years in group 2. Bladder neck hypertrophy decreased from 2.3±1.0 to 2.0±0.5 in a mean time of 52.0 (34-52) weeks in group 1 where as it decreased from 2.2±0.5 to 1.6±0.3 in a mean time of 32.0 (22-52) weeks. Symptomatically patients in group 2 who received alpha-1 blocker therapy after valve ablation were better and had quick resolution of bladder neck hypertrophy. Conclusions: Use of alpha-1 blocker therapy in patients of posterior urethral valve with bladder neck hypertrophy helps in quick resolution of bladder neck hypertrophy. J Med Sci 2009;12(1):3-7.

Preoperative Platelet to Lymphocyte Ratio Is Associated with Early Morbidity and Mortality after Coronary Artery Bypass Grafting

2015 ◽  
Vol 18 (6) ◽  
pp. 255 ◽  
Author(s):  
Hüseyin Şaşkın ◽  
Çagrı Düzyol ◽  
Kazım Serhan Özcan ◽  
Rezan Aksoy ◽  
Mustafa Idiz
Keyword(s):  
Coronary Artery ◽  
Coronary Artery Bypass Grafting ◽  
Coronary Artery Bypass ◽  
Artery Bypass ◽  
Bypass Grafting ◽  
Platelet To Lymphocyte Ratio ◽  
Artery Bypass Grafting ◽  
Lymphocyte Ratio ◽  
Group 2 ◽  
Group 1

<strong>Objective:</strong> To investigate the association of platelet to lymphocyte ratio to mortality and morbidity after coronary artery bypass grafting operation.<br /><strong>Methods:</strong> We evaluated records of 916 patients who underwent coronary artery bypass grafting operation between January 2009 and May 2014 retrospectively. Patients were grouped as Group 1 (n = 604) if the platelet to lymphocyte ratio was above 142 and Group 2 (n = 312) if platelet to lymphocyte ratio was below 142.<br /><strong>Results:</strong> The number of patients who developed a neurologic event during the hospital stay and in the first postoperative month was 7 (1.2%) in Group 1 and 12 (3.8%) in Group 2 for which the difference was statistically significant (P = .007). Early term mortality occurred in 3 patients (0.5%) in Group 1 and in 10 patients (3.2%) in Group 2 for which the difference was statistically highly significant (P = .001). In univariate and multivariate regression analysis, the preoperative platelet to lymphocyte ratio was determined as an independent risk factor for occurrence of atrial fibrillation in the early postoperative period, reoperation for sternum dehiscence, occurrence of a neurologic event, prolonged stay in the hospital and mortality.<br /><strong>Conclusion:</strong> In this study, elevated levels of platelet to lymphocyte ratio were associated with mortality and morbidity after coronary artery bypass grafting operation.

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