Journal of African Earth Sciences, ( ISI ), Volume (176), No (104124), Year (2021-4) , Pages (104124-18)

Title : ( Dolomitization models in the Sibzar Formation (Middle Devonian), Binalood Mountains (NE Iran): Based on the petrographic and geochemical evidence )

Authors: Abolfazl Jamshidipour , Mohammad Khanehbad , Sayyed Reza Moussavi Harami , Asadollah Mahboubi ,

Access to full-text not allowed by authors

Citation: BibTeX | EndNote

Abstract

Lithostratigraphically, Sibzar Formation (Middle Devonian) in the Kharv section (Binalood Mountains, NE Iran) with a thickness of 334 m consists of three units (in ascending order): dolostone with intercalations sandstone, middle basaltic sill, and upper dolostone. Three types of dolomite have been identified based on crystal size and shape. Fine crystalline dolomite (D1; finer than 30 μm) consist of Nonplanar-a dolomites. Fine to medium crystalline dolomite (D2; 20 to 150 μm) consist of mostly Nonplanar-a dolomites and some dolomites are Planar-s and Planar-e. Vein dolomites (Vd; 40 to 700 μm) have a very diverse crystalline texture and are mostly Planar-s, Planar-e and some Nonplanar-a. Cathodoluminescence technique studies also showed that most of these dolomites have dull red luminescence, in some veins with bright red luminescence and zoning. Based on the X-ray diffraction (XRD) and ICP-OES, all dolomites are nearly stoichiometric dolomite and relatively well ordered. Elemental analysis and stable isotope studies show that the concentration of minor elements such as sodium (D1: 822–1365 ppm; D2: 1016–1241 ppm; Vd: 971–1072 ppm), strontium (D1: 257–963 ppm; D2: 134–1334 ppm; Vd: 144–379 ppm), manganese (D1: 560–3675 ppm; D2: 1039–2168 ppm; Vd: 1818–3454 ppm), and iron (D1: 15997-30080 ppm; D2: 8288–18456 ppm; Vd: 19304-25618 ppm) in these dolomites were high and the values of the stable isotope of oxygen (D1: -9.1 to −5.9‰; D2: -7.6 to −6.1‰; Vd: -11.1 to −7.2‰) and carbon (D1: -3.5 to −2.5‰; D2: -5.2 to −1.3‰; Vd: -2 to −1.6‰) were low. The high values of iron and manganese and depletion of the carbon and oxygen isotopes can be related to the effects of high-temperature diagenetic fluids caused by basaltic sill during the burial. These dolomites formed in tidal environment and burial diagenesis in this Formation. Seawater, connate seawaters, saline basinal fluid, and magnesium-rich hypersaline fluids are the main source of magnesium ion (Mg2+) for dolomites of this Formation.

Keywords

Primary dolomite Model of dolomitization Stable isotope Elemental geochemistry Sibzar formation Middle devonian
برای دانلود از شناسه و رمز عبور پرتال پویا استفاده کنید.

@article{paperid:1083633,
author = {Jamshidipour, Abolfazl and Khanehbad, Mohammad and Moussavi Harami, Sayyed Reza and Mahboubi, Asadollah},
title = {Dolomitization models in the Sibzar Formation (Middle Devonian), Binalood Mountains (NE Iran): Based on the petrographic and geochemical evidence},
journal = {Journal of African Earth Sciences},
year = {2021},
volume = {176},
number = {104124},
month = {April},
issn = {1464-343x},
pages = {104124--18},
numpages = {-104106},
keywords = {Primary dolomite Model of dolomitization Stable isotope Elemental geochemistry Sibzar formation Middle devonian},
}

[Download]

%0 Journal Article
%T Dolomitization models in the Sibzar Formation (Middle Devonian), Binalood Mountains (NE Iran): Based on the petrographic and geochemical evidence
%A Jamshidipour, Abolfazl
%A Khanehbad, Mohammad
%A Moussavi Harami, Sayyed Reza
%A Mahboubi, Asadollah
%J Journal of African Earth Sciences
%@ 1464-343x
%D 2021

[Download]