Petrology and Petro Genesis of Alkaline and Calc-Alkaline Lamprophyres in the NW Iran (original) (raw)

Petrography, geochemistry and tectono-magmatic setting of the dykes of the north and the west of Zahedan (Southeast Iran)

Petrology, 2017

The Eocene dykes in the north and the west of Zahedan exposed into the flysch and Zahedan granitoid rocks in the Sistan suture zone. These rocks, including mafic dykes, ultramafic and felsic are mostly alkaline in nature and sometimes are contaminated. The dykes in discussion, display mostly porphyritic and glomeroporhyric textures. Plagioclase, hornblende and biotite are the main phases as well as the matrix of the rocks. The presence of rounded plagioclase and corrosion Gulf of quartz, normative changes and variation in minor and trace elements are indicative of contamination with continental crust. Enrichment of LREE relative to HREE and the lack of Eu anomaly are important characteristics of all of the studied rocks. High ratios (La/Sm)N, and (La/Yb)N and(Sm/Yb)N and the alkaline nature of most of the samples, indicate a melting process about 1 percent of a mantle with garnet lherzolite composition. Such conditions may be completion of subduction of Sistan oceanic lithosphere b...

Volcano-plutonic relations in Lat-Bolukan district (North of Qazvin, Western Alborz): Petrogenetic analysis and geochemical modeling

Petrology, 2017

The Lat-Blukan area situated on the western Alborz zone, 45 Km to the north of Qazvin. The area contains intrusive and extrusive bodies with intermediate to acidic composition belonging to Eocene or younger in age (Karaj Formation). This lithological sequence can be divided into three main facies: sedimentary-pyroclastic deposits resulted from explosive alternative eruptions in a shallow-depth sedimentary basin, andesitic lava flows from subaerial effusive fissure eruptions and subvolcanic bodies including dioritic bodies, dacitic domes and parallel dyke swarms. Dykes also are subdivided into andesitic feeder dykes and post-magmatic dioritic dyke. Several evidences including the Ba/La > 15, Ba/Ta > 450, enrichment of LREEs relative to HREEs, enrichment of LILEs and depletion of HSFEs (Ti and Ta) as well as different tectonic setting diagrams, the magmatic rocks appertain to the continental active margin. Geochemically and especially based on geochemical modeling of magmatic p...

Petrology and Geochemistry of Shakh Sefid Granitoid and related skarn in the North of Rayen (southeastern of Kerman)

Petrology, 2017

The Shakh Sefid Granitoid pluton and related Skarn are located 80 Km in the southeastern of Kerman and 20 Km north of Rayen. This area is geologically located in the southeastern of the Lut block in the Central Iran. The Shakh Sefid Granitoid with Eocene-Oligocene age cuts the Cretaceous sedimentary rocks and led to the formation of Skarn. The granitoids are granite and granodiorite in composition composing of quartz, plagioclase, orthoclase, as primary minerals, biotite as minor and chlorite and sericite as secondary minerals. The sedimentary rocks are shale, sandstone, siltstone and limestone. Metamorphic rocks are marble and Skarns. The Skarn is calcic type. Garnet (grossular-andradite), tremolite and magnetite are the main minerals that are often accompanied with hematite, goethite and limonite. Pyrite, chalcopyrite and copper carbonate (malachite and azurite) are the other minerals in Skarn. Geochemical studies show that the amount of major and minor elements of granitoid wit...

Investigation of hydrocarbon generation potential of Paleocene sediments in the southern Caspian Basin

2020

The present study investigates the geochemical properties of potential source rocks in the eastern Caspian Basin from Alborz structural zone. For this purpose, sections of Suchelma and Purva in south of Neka and an outcrop in south of Sari were selected. The studied samples of sedimentary source rocks of the Paleocene age were analyzed based on Rock-Eval analysis method. The results of RockEval pyrolysis and organic petrography results of probable source rock sediments in one of the exploration wells of Gorgan plain were also studied. According to the results, most of the outcrops samples are immature and were deposited in a regressive continental environment. The samples of exploration borehole studied, are good in terms of organic matter richness but in terms of the amount of kerogen maturation are immature. According to the results of this study, these samples have weak hydrocarbon generating power and total organic carbon content of about 1% as well as kerogen type III. It was a...

گسترش و تنوع گونه های سفال دوران اسلامی در سکونت های دشت نرماشیر کرمان / Distribution, Continuity and Diversity of Islamic Ceramics in the Settlements of Narmashir Plain, Kerman (In Persian)

2019

نرماشیر در صدر اسلام، یکی از پنج ولایت کرمان بود. اما توجه باستان‌شناسان به بم و جیرفت سبب غفلت از نرماشیر شده و شناخت کافی از سفال اسلامی نرماشیر وجود ندارد. عدم شناخت سفال نرماشیر از یک‌سو، و نقش سفال در گاهنگاری و شناخت تغییرات فرهنگی از دیگر سو، نشانگر ضرورت این پژوهش است. پرسش‌ها این‌ست که گونه‌های سفال اسلامی در نرماشیر چیست و به چه ادواری تعلّق دارند؟ فراز و فرود حیات در نرماشیر و روابط فرامنطقه‌ای آن براساس داده‌های سفالی چگونه بوده‌ است؟ ویژگی‌های تولید و سبک محلّی سفال در نرماشیر چیست؟ اهداف پژوهش عبارتنداز: مطالعه‌ی سفال اسلامی نرماشیر و شواهد تولید، گونه‌شناسی و گاهنگاری مقایسه‌ای و نسبی سفال‌ها و تبیین روند تداوم حیات در نرماشیر. روش گردآوری داده‌ها، میدانی-اسنادی، و روش پژوهش توصیفی-تحلیلی است1. برپایه‌ی نتایج، سفال اسلامی نرماشیر شامل گونه‌های: ساده‌ی بی‌لعاب، نقش‌کنده، افزوده، قالب‌زده، مُهری، شبه پیش‌ازتاریخی، لعابدار تک‌رنگ، نقش کنده یا افزوده زیرلعاب، گلابه‌ای، لعاب‌پاشیده، اسگرافیتو، نقاشی زیرلعاب، نقاشی روی لعاب، زرین‌فام و آبی‌و‌سفید است. این گونه‌ها، ارتباطات فرهنگی با: جیرفت، غبیرا، سیرجان، میناب، کیش، سیراف، نیشابور، اسفراین، ری، اصفهان، قصرابونصر، مرودشت، سی‌سخت، بویراحمد، شوش، رأس‌الخیمه امارات، مُسندَم عمان، حضرموت یمن، قلعه بحرین، بصره، سامرا، رقّه و لشکری‌بازار را نشان می‌دهند. برخی نمونه‌های سفال نرماشیر وارداتی و تعدادی تولید محلّی، اما تقلیدی هستند. نمونه‌های قالب‌زده‌ی بی‌لعاب، تولید محلّی و دارای نقوش کاملاً محلّی هستند. همچنین، حیات شهر نرماشیر از دوره‌ی ساسانی آغاز شده، و در دوره‌ی‌ سلاجقه‌ی کرمان و قراختاییان به اوج می‌رسد و تا دوره‌ی تیموری تداوم داشته است؛ اما جمعیت آن در دوره‌ی صفوی کاهش می‌یابد و پس از صفویان متروک شده و تعدادی روستا در دشت باقی ‌می‌ماند. In the early Islamic sources, Narmashir has introduced as one of the five main cities of Kerman and a part of the southeast economic exchange network. But it is unknown because archaeologists have often focused on the Bam and Jiroft. The questions are: what are the types of Islamic ceramics in the Narmashir, and what periods are they related to? How does the ups and downs of life in the Narmashir and its transnational cultural relations? What are the features of local ceramic production in the Narmashir plain? The purposes of the research are: “the study of Islamic ceramic and production evidence in the Narmashir”, “typology and relative chronology of ceramics”, and “explaining the periods of the prosperity of Narmashir”. The data have collected via “documentary and field” method, and the research method is “descriptive-analytical”. Based on the results, the ceramic types in Narmashir include the unglazed simple wares, wares with carving or added motifs, molded wares, pseudo-prehistoric ceramics, monochrome glaze, underglaze carving or added motifs, slip-painted wares, Sgraffiato, underglaze or overglaze painting, lusterware, and blue and white wares. These types of ceramics show the cultural relations with Jiroft, Gobayra, Sirjan, Soghan, Minab, Kish, Siraf, Nishapur, Esfahan, Rayy, Qasr-e Abu-Nasr, Marvdasht, Pasargadae, Sisakht, Boyer Ahmad, Susa, Ras al-Khaimah, Musandam, Hadramaut, Bahrain, Basra, Samarra, Raqqa, and Lashkari Bazar. Some samples of ceramics are imported in Narmashir. Some others are local, but they are imitated from foreign samples. The unglazed molded wares are locally produced and they have localized motifs. Also, the life of the old city of Narmashir has started from the Sassanid era, it peaked during the Saljuq and Qara Khitai period, and continued until the Timurid. But, its population declined during the Safavid period, and it has abandoned after the Safavids. So, only a few villages remained in the plain.

Occurrence and chemistry of supergene sulfide and oxide minerals in Mahour polymetal ore deposit, west of Nehbandan

Petrology, 2013

Mahour polymetal ore deposit is located in the eastern margin of Lut block, 130 Km west of Nehbandan. The supergene mineralization mainly occurs as a north-south trend in the Tertiary altered volcanic rocks. The supergene minerals mainly occur as iron hydroxide, Cu-carbonates, Cu and Pb sulfates and Cu sulfides. Goethite, malachite, azurite, chalcosite, covellite, linarite and atacamite are common supergene minerals in the Mahour ore deposit that were formed by oxidation of the hypogene sulfides. Some of these minerals were analyzed by electron probe microanalyses (EPMA). Ag content is considerable in most of these minerals. Covellite from the Mahour has high Pb, Zn and Ag contents. The chemistry of the supergene minerals and the way of their formation will be discussed in this paper.