Primary geochemical haloes and alteration zoning applied to gold exploration in the Zarshuran Carlin-type deposit, northwestern Iran

A mise‐a‐la‐masse survey was carried out in Bhukia area, Banswara district, Rajasthan, India for auriferous sulfide occurrences. This area was originally surveyed for copper mineralization. Exploratory drilling, however, proved it to be economically not viable. The area was reopened for geophysical surveys when grab samples indicated the presence of gold. Initial geophysical surveys for copper mineralization showed electromagnetic, induced polarization, and resistivity anomalies. At first, one borehole was drilled for gold exploration on the basis of initial geophysical surveys. It encountered massive sulfide mineralization in association with gold. Borehole logging and a mise‐a‐la‐masse survey were carried out in this borehole. Three further boreholes drilled on the basis of the mise‐a‐la‐masse results encountered massive sulfide mineralization in association with gold. One of the three boreholes, 100 m from the first borehole along strike, was used for another set of mise‐a‐la‐masse measurements. A composite equipotential map was prepared using the results of mise‐a‐la‐masse results of both the boreholes. The equipotential contours show a north‐northwest‐south‐southeast trend of mineralization. The boreholes drilled on the basis of the mise‐a‐la‐masse results have delineated a strike length of more than 500 m of gold‐bearing sulfide mineralization. The sulfide content ranges from 10 to 40% and gold concentration ranges from 2 to 6 ppm. The dip and plunge of the lode, as anticipated from the mise‐a‐la‐masse results, are toward the west and north, respectively. Mise‐a‐la‐masse surveys are continuing in the adjoining areas.

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Lake Neor reveals how mountain vegetation responded to 7000 years of hydroclimate variability in northwestern Iran

Journal of Quaternary Science ◽

10.1002/jqs.3310 ◽

2021 ◽

Author(s):

Khadijeh Alinezhad ◽

Elias Ramezani ◽

Morteza Djamali ◽

Arash Sharifi ◽

Alireza Naqinezhad ◽

...

Keyword(s):

Hydroclimate Variability ◽

Northwestern Iran ◽

Mountain Vegetation

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Mineralogy, mineral chemistry and thermobarometry of post-mineralization dykes of the Sungun Cu–Mo porphyry deposit (Northwest Iran)

Open Geosciences ◽

10.1515/geo-2020-0009 ◽

2020 ◽

Vol 12 (1) ◽

pp. 764-790

Author(s):

Amin Allah Kamali ◽

Mohsen Moayyed ◽

Nasir Amel ◽

Fadaeian Mohammad ◽

Marco Brenna ◽

...

Keyword(s):

Active Continental Margin ◽

Mineral Chemistry ◽

Quartz Diorite ◽

Alkaline Magmatism ◽

Porphyry Deposit ◽

Average Percentage ◽

The North ◽

Northwestern Iran ◽

Subduction System ◽

Late Stages

AbstractThe Sungun copper–molybdenum porphyry deposit is located in the north of Varzaghan, northwestern Iran. The Sungun quartz-monzonite is the oldest mineralized intrusive body in the region and was emplaced during the Early Miocene. Eight categories of the late and unmineralized dykes, which include quartz diorite, gabbrodiorite, diorite, dacite, microdiorite and lamprophyre (LAM), intrude the ore deposit. The main mineral phases in the dykes include plagioclase, amphibole and biotite, with minor quartz and apatite and secondary chlorite, epidote, muscovite and sericite. The composition of plagioclase in the quartz diorite dykes (DK1a, DK1b and DK1c) varies from albite-oligoclase to andesine and oligoclase to andesine; in the diorite, it varies from andesine to labradorite; in the LAM, from albite to oligoclase; and in the microdiorite (MDI), it occurs as albite. Amphibole compositions are consistent with classification as hornblende or calcic amphibole. Based on their AlIV value (less than 1.5), amphibole compositions are consistent with an active continental margin affinity. The average percentage of pistacite (Ps) in epidotes formed from alteration of plagioclase and ferromagnesian minerals is 27–23% and 25–30%, respectively. Thermobarometric studies based on amphibole and biotite indicate approximate dyke crystallization temperature of 850–750℃, pressure of 231–336 MPa and high fO2 (>nickel-nickel-oxide buffer). The range of mineral compositions in the postmineralization dyke suite is consistent with a genetic relationship with the subduction of the Neotethys oceanic crust beneath the continental crust of the northwest part of the Central Iranian Structural Zone. Despite the change from calc-alkaline to alkaline magmatism, the dykes are likely related to the late stages of magmatic activity in the subduction system that also generated the porphyry deposit.

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Significance of ferruginous pisoliths and interface sampling for gold exploration in the covered terrains

Journal of Geochemical Exploration ◽

10.1016/j.gexplo.2021.106794 ◽

2021 ◽

pp. 106794

Author(s):

Walid Salama ◽

Ravi Anand ◽

Louise Schoneveld ◽

Ryan Noble ◽

Jordan Rogers

Keyword(s):

Gold Exploration

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Epidemiological characteristics and mortality risk factors among COVID-19 patients in Ardabil, Northwest of Iran

BMC Emergency Medicine ◽

10.1186/s12873-021-00463-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Davoud Adham ◽

Shahram Habibzadeh ◽

Hassan Ghobadi ◽

Shabnam Asghari Jajin ◽

Abbas Abbasi-Ghahramanloo ◽

...

Keyword(s):

Clinical Presentation ◽

Multiple Model ◽

Shortness Of Breath ◽

Imaging Data ◽

Demographic Information ◽

Runny Nose ◽

Data Registration ◽

Northwestern Iran ◽

Northwest Of Iran ◽

Epidemiological Characteristics

Abstract Background Coronavirus disease highly contagious, is prevalent in all age and sex groups infecting the respiratory system. The present study seeks to investigate the epidemiology and effective factors in mortality of patients with COVID-19 in Ardabil province, northwestern Iran. Methods In a retrospective study, the hospitalized patients with laboratory-diagnosed COVID-19 between February to August 2020 were enrolled. The data registration portal was designated according to Iranian Ministry of Health and Medical Education guidelines. In this portal, demographic information, clinical presentation, laboratory and imaging data were registered for patients in all hospitals in the same format. The Hosmer-Lemeshow strategy was used for variable selection in a multiple model. Results Of the patients involved 2812(50.3%) were male and 150 (2.7%) had contact with a confirmed case of COVID-19 in the last 14 days. Pre-existing comorbidity was reported in 1310 (23.4%) patients. Of all patients, 477(8.5%) died due to COVID-19. the result of the multiple logistic regression model indicated that after adjusting for other factors, higher age (OR = 3.11), fever or chills (OR = 1.61), shortness of breath (OR = 1.82), fatigue (OR = 0.71), headache (OR = 0.64), runny nose (OR = 1.54), Skeletal muscle pain (OR = 1.53), hospitalization (OR = 5.66), and hospitalization in ICU (OR = 5.12) were associated with death. Conclusions Hospitalization had the strongest effect on mortality followed by hospitalization in ICU, and higher age. This study showed that having some extra-pulmonary symptoms in contrast with pulmonary symptoms can predict as good prognostic factors.

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