MAHNAZ KHODAMI - Academia.edu (original) (raw)

Papers by MAHNAZ KHODAMI

Research paper thumbnail of Prediction of Durability Properties of Igneous Rocks as Railway Ballast by Simultaneously Considering the Petrographical, Geochemical, and Physical Characteristics

Journal of Materials in Civil Engineering, Dec 31, 2023

Research paper thumbnail of Mineralogical and Geochemical characteristics of the Chah-Shur Clay Deposit, Southeast of Isfahan, Iran

Iranian Journal of Earth Sciences, Oct 1, 2018

Research paper thumbnail of Early Cambrian highly fractionated granite, Central Iran: Evidence for drifting of northern Gondwana and the evolution of the Proto-Tethys Ocean

Precambrian Research, Aug 1, 2021

Abstract The Zarin granitic body is located in the eastern part of the Yazd Block in the Central ... more Abstract The Zarin granitic body is located in the eastern part of the Yazd Block in the Central Iran microcontinent. The granite has variable granular to mylonitic textures. New zircon U-Pb dating shows that the granitic rocks crystallized at 535–530 Ma. The pluton has high SiO2 abundances (72.1–77.5 wt%), K2O (4.4–6.3 wt%) and low MgO (0.2–0.7 wt%) contents, as well as high K2O/Na2O (1.10–1.97) and A/CNK (molar ratio of Al2O3/(CaO + Na2O + K2O)) 0.9–1.1 ratios, and is dominantly peraluminous. The granite is enriched in light rare earth elements (LREEs) relative to heavy REEs (HREEs), has negative Eu anomalies, and is extremely depleted in Nb, Ba, P, Ta and Ti. It is also characterized by variable but commonly high 87Sr/86Sr(i) (0.7018–0.7093) and negative eNd(i) values of −1.1 to −2.6. The geochemical features indicate that the rocks are highly fractionated I-type granite and have undergone extensive fractional crystallization of hornblende, biotite and feldspar. Results are consistent with melting of an evolved lower crust source during the subduction of the Proto-Tethys Ocean. The emplacement of the Zarin granite is contemporaneous with the extension of a Cadomian continental arc on the north side of Gondwana, that rifted away to create the Rheic Ocean to its south. Cadomian basement rocks in Iran are interpreted as an important link between western and eastern sectors of the Late Proterozoic-Early Paleozoic orogenic belts along the northern side of Gondwana, and the histories of the Rheic, Iapetus and Proto-Tethyan oceans

Research paper thumbnail of Tectonic transition from Ediacaran continental arc to early Cambrian rift in the NE Ardakan region, central Iran: Constraints from geochronology and geochemistry of magmatic rocks

Journal of Asian Earth Sciences, Feb 1, 2022

Research paper thumbnail of Insights from Zircon Morphology and Geochemical Signatures of Ghaleh-Dezh Granitic Pluton, Azna

Zircon is a tetragonal crystal and records different episode(s) of geology in external morphology... more Zircon is a tetragonal crystal and records different episode(s) of geology in external morphology and internal textures. Factors affecting the shape of the zircon crystals are the composition, possibly the temperature of the crystallization and water content in magma. The zircon typology of the Ghaleh-Dezh granite mostly introduces the fields P5 in classification of Pupin (1990), therefore, show mantle source for the granite. The dominant morphology of the zircon grains reveals a strong dominance of {100} prisms and {101} pyramids over {110} prisms and {211} pyramids. The dominant morphology shows high alkalinity, the temperature of crystallization about 850 ºC and dry alkalic nature for the granite. Absent of hydrozircon overgrowth indicate dry magma. Also, the Zr saturation temperature based on zircon solubility reflects a mean temperature of 835 °C. All of information is corresponded by petrography and geochemical evidences and also with a-type granitic magma that has mantle and crust sources.

Research paper thumbnail of 235 Diagnostic value of proliferative markers Ki-67 and Repp 86 in distinguishing between malignant and benign mesothelial proliferations

Research paper thumbnail of The use of chemical and textural indices to predict geotechnical properties of granites with different degrees of weathering

Bulletin of Engineering Geology and the Environment

Research paper thumbnail of Comparative study of mineralogy and geochemistry of altered felsic rocks in Yazd province

مجله بلورشناسی و کانیشناسی ایران, Mar 1, 2021

Research paper thumbnail of Mineral chemistry and geothermo-barometry based on amphibole of alkali gabbro dykes of Zarigan, northeast of Bafq

Iranian Journal of Crystallography and Mineralogy

Research paper thumbnail of A record of Late Cambrian–Early Ordovician arc magmatism in Yazd block, Central Iran

Arabian Journal of Geosciences

Research paper thumbnail of Petrogenesis of Pliocene-Quaternary Volcanic Rocks in Isfahan Province: Insight on Adakite Magmatism

The Pliocene calc-alkaline volcanic rocks are exposed in two areas in southeast and northwest of ... more The Pliocene calc-alkaline volcanic rocks are exposed in two areas in southeast and northwest of Isfahan and consist of andesites and dacites. Based on geochemical data and multielements pattern, these rocks are medium to high calc-alkaline suite and they show LILE and LREE enriched normalized multi-element patterns, and negative Nb and Ti. Condritenormalized REE patterns display a steep decrease from LREE to HREE without any Eu anomaly. They have higher SiO2 and Sr content and Sr/Y and La/Yb ratios and low MgO, Mg#, Y and Yb contents than the normal calc-alkaline volcanic rocks. These volcanic rocks show adakite characteristics. These features are consistent with ratios obtained from orogenic related volcanic rocks. These rocks may have been produced by partial melting of thickened lower continental crust or slab probably transformed to eclogite or garnet -amphibolite. HREE and Y depleted pattern suggest the existence of garnet and amphibole as a residue in the source.

Research paper thumbnail of Pliocene–Quaternary Adakite volcanism in the Isfahan area, Central Iranian magmatic belt

Neues Jahrbuch für Mineralogie - Abhandlungen, 2009

Abstract: Pliocene-Quaternary calc-alkaline volcanic rocks are exposed in two areas southeast and... more Abstract: Pliocene-Quaternary calc-alkaline volcanic rocks are exposed in two areas southeast and northwest of the Isfahan area in the Urumieh-Dokhtar magmatic belt. These volcanic rocks consist of basaltic andesites, andesites and dacites, which can be found as ...

Research paper thumbnail of Geochemical constraints on the genesis of the volcanic rocks in the southeast of Isfahan area, Iran

Arabian Journal of Geosciences, 2009

Late Miocene-Pliocene to Quaternary calcalkaline lava flows and domes are exposed in southeast of... more Late Miocene-Pliocene to Quaternary calcalkaline lava flows and domes are exposed in southeast of Isfahan in the Urumieh Dokhtar magmatic belt in the Central Iran structural zone. These volcanic rocks have compositions ranging from basaltic andesites, andesites to dacites. Geochemical studies show these rocks are a medium to high K calc-alkaline suite and meta-aluminous. Major element variations are typical for calc-alkaline rocks. The volcanic rocks have SiO 2 contents ranging between 53.8% and 65.3%. Harker diagrams clearly show that the dacitic rocks did not form from the basaltic andesites by normal differentiation processes. They show large ion lithophile elements-and light rare earth elements (LREE)enriched normalized multielement patterns and negative Nb, Ti, Ta, and P. Condrite-normalized REE patterns display a steep decrease from LREE to light rare earth elements without any Eu anomaly. These characteristics are consistent with ratios obtained from subduction-related volcanic rocks and in collision setting. The melting of a heterogeneous source is possible mechanism for their magma genesis, which was enriched in incompatible elements situated at the upper continental lithospheric mantle or lower crust. The geochemical characteristics of these volcanic rocks suggested that these volcanic rocks evolved by contamination of a parental magma derived from metasomatized upper lithospheric mantle and crustal melts.

Research paper thumbnail of Magmatic evolution recorded by phenocrysts in volcanic rocks southeast of Isfahan

Late Miocene–Pliocene calc-alkaline volcanic rocks are exposed southeast of Isfahan in the Urumie... more Late Miocene–Pliocene calc-alkaline volcanic rocks are exposed southeast of Isfahan in the Urumieh-Dokhtar magmatic belt. Volcanic rocks consist of lava flows and domes, chiefly basaltic andesites, andesites and dacites. Minerals in the volcanic rocks exhibit degrees of disequilibrium features. Plagioclase as dominant mineral in these rocks generally displays reverse and oscillatory zoning; sieve or dusty and clear populations, cores are unusually Ca-rich. Hornblende and biotitephenocrysts have reaction rims indicating disequilibrium growth during late stage crystallization. Quartz phenocrysts are corroded and embayed and a few show augite reaction rims. Criteria such as: a) development of sieve textures in plagioclase b) reaction rims in mafic minerals c) reverse zoning and heterogeneity of plagioclase rims d) the resorbed and embayed phenocrysts; support magma mixing as an important process in the evolution of these rocks.

Research paper thumbnail of Early Cambrian highly fractionated granite, Central Iran: Evidence for drifting of northern Gondwana and the evolution of the Proto-Tethys Ocean

Research paper thumbnail of Mineralogical and Geochemical characteristics of the Chah-Shur Clay Deposit, Southeast of Isfahan, Iran

The Chah-Shur clay deposit is located in 150 km southeast of Isfahan. Eocene igneous rocks and Qu... more The Chah-Shur clay deposit is located in 150 km southeast of Isfahan. Eocene igneous rocks and Quaternary deposits cover the area. Eocene volcanic rocks include andesite and tuff. The rocks belong to magmatic activities of Urumieh-Dokhtar magmatic belt. Alteration of the vitric and lithic tuff units has produced the clay deposit. Based on the petrographic studies the main minerals in tuff units are plagioclase, K-feldspar and quartz. The major phases in clay deposit are kaolinite, illite, montmorillonite, quartz, albite and orthoclase. Also, muscovite, chlorite and hematite are as minor phases. The mineralogical studies show an intermediate alteration. The clay deposits can be formed by supergene or hypogene processes; while the combination of both of them can result in the formation of mixed type clay. The geochemical data of Chah-Shur clay deposit show scattering between hypogene and supergene types. The abundance of Fe2O3+TiO2 vs Cr+Nb and Zr vs TiO2, as well asSr+Ba vs Ce+Y+La s...

Research paper thumbnail of Mineralogy, geochemistry, and genesis of the Garak Baghi kaolin deposit in the northwest of Saveh, Iran

The Garak Baghi kaolin deposit is located in Markazi province and in 75 km northwest of Saveh. It... more The Garak Baghi kaolin deposit is located in Markazi province and in 75 km northwest of Saveh. It belongs to the Iranian central structural zone. Eocene-Miocene igneous rocks consist of dacite, andesite, tuff, and other pyroclastic rocks and acidic to intermediate intrusive rocks covered the area. Based on petrographic studies, the main minerals in the volcanic rocks are plagioclase, K-feldspar, and quartz. The tectonic processes have affected the area and formed the main faults and fractures that developed the hydrothermal alteration. Hydrothermal alteration has produced clay deposit. Clay deposits contain kaolinite, illite, and the residual materials of altered feldspar with impurity phase such as gypsum, calcite, anatase, and iron compositions. The quality of clay soils especially near the fault zones has been reduced by iron composition. Geochemical studies show that the rocks are medium-K calc-alkaline and meta-aluminous. Based on chemical index of alteration (CIA) and chemical...

Research paper thumbnail of Petrography and Mineral Chemistry of Volcanic Rocks in Gowris Mountain, South East Isfahan

Research paper thumbnail of Tectonic transition from Ediacaran continental arc to early Cambrian rift in the NE Ardakan region, central Iran: Constraints from geochronology and geochemistry of magmatic rocks

Journal of Asian Earth Sciences

Research paper thumbnail of Crystal size and shape distribution of plagioclase in the basaltic andesites, North of Gavkhouni

Iranian Journal of Crystallography and Mineralogy

Plagioclase is the most abundant mineral in basaltic andesites in the north Gavkhouni. Olivine an... more Plagioclase is the most abundant mineral in basaltic andesites in the north Gavkhouni. Olivine and pyroxene are the other rock forming mineral there. In their 3dimensional shapes, they are unequal and varies between bladed to prolate. Plagioclase sometimes exhibit dusty texture, oscillatory zoning and sinusoid growth. Based on crystal size distribution data, the rate of crystal nucleation of plagioclase varies between 2.77*10-8-3.07*10-8 mm-3 s-1 in 71.78-17.77 years. The results indicate the higher nucleation rate, rapid cooling and a short crystal residence time in the magma chamber. The crystal size distribution diagrams show the high frequency of smaller crystals and the coarsening of the average crystals. However, the presence of two populations of plagioclase indicates the interfering of new magma with the same chemical composition and new crystal population into the magma chamber. This event can increase the volume of the magma chamber pressure and eruption of the magma.

Research paper thumbnail of Prediction of Durability Properties of Igneous Rocks as Railway Ballast by Simultaneously Considering the Petrographical, Geochemical, and Physical Characteristics

Journal of Materials in Civil Engineering, Dec 31, 2023

Research paper thumbnail of Mineralogical and Geochemical characteristics of the Chah-Shur Clay Deposit, Southeast of Isfahan, Iran

Iranian Journal of Earth Sciences, Oct 1, 2018

Research paper thumbnail of Early Cambrian highly fractionated granite, Central Iran: Evidence for drifting of northern Gondwana and the evolution of the Proto-Tethys Ocean

Precambrian Research, Aug 1, 2021

Abstract The Zarin granitic body is located in the eastern part of the Yazd Block in the Central ... more Abstract The Zarin granitic body is located in the eastern part of the Yazd Block in the Central Iran microcontinent. The granite has variable granular to mylonitic textures. New zircon U-Pb dating shows that the granitic rocks crystallized at 535–530 Ma. The pluton has high SiO2 abundances (72.1–77.5 wt%), K2O (4.4–6.3 wt%) and low MgO (0.2–0.7 wt%) contents, as well as high K2O/Na2O (1.10–1.97) and A/CNK (molar ratio of Al2O3/(CaO + Na2O + K2O)) 0.9–1.1 ratios, and is dominantly peraluminous. The granite is enriched in light rare earth elements (LREEs) relative to heavy REEs (HREEs), has negative Eu anomalies, and is extremely depleted in Nb, Ba, P, Ta and Ti. It is also characterized by variable but commonly high 87Sr/86Sr(i) (0.7018–0.7093) and negative eNd(i) values of −1.1 to −2.6. The geochemical features indicate that the rocks are highly fractionated I-type granite and have undergone extensive fractional crystallization of hornblende, biotite and feldspar. Results are consistent with melting of an evolved lower crust source during the subduction of the Proto-Tethys Ocean. The emplacement of the Zarin granite is contemporaneous with the extension of a Cadomian continental arc on the north side of Gondwana, that rifted away to create the Rheic Ocean to its south. Cadomian basement rocks in Iran are interpreted as an important link between western and eastern sectors of the Late Proterozoic-Early Paleozoic orogenic belts along the northern side of Gondwana, and the histories of the Rheic, Iapetus and Proto-Tethyan oceans

Research paper thumbnail of Tectonic transition from Ediacaran continental arc to early Cambrian rift in the NE Ardakan region, central Iran: Constraints from geochronology and geochemistry of magmatic rocks

Journal of Asian Earth Sciences, Feb 1, 2022

Research paper thumbnail of Insights from Zircon Morphology and Geochemical Signatures of Ghaleh-Dezh Granitic Pluton, Azna

Zircon is a tetragonal crystal and records different episode(s) of geology in external morphology... more Zircon is a tetragonal crystal and records different episode(s) of geology in external morphology and internal textures. Factors affecting the shape of the zircon crystals are the composition, possibly the temperature of the crystallization and water content in magma. The zircon typology of the Ghaleh-Dezh granite mostly introduces the fields P5 in classification of Pupin (1990), therefore, show mantle source for the granite. The dominant morphology of the zircon grains reveals a strong dominance of {100} prisms and {101} pyramids over {110} prisms and {211} pyramids. The dominant morphology shows high alkalinity, the temperature of crystallization about 850 ºC and dry alkalic nature for the granite. Absent of hydrozircon overgrowth indicate dry magma. Also, the Zr saturation temperature based on zircon solubility reflects a mean temperature of 835 °C. All of information is corresponded by petrography and geochemical evidences and also with a-type granitic magma that has mantle and crust sources.

Research paper thumbnail of 235 Diagnostic value of proliferative markers Ki-67 and Repp 86 in distinguishing between malignant and benign mesothelial proliferations

Research paper thumbnail of The use of chemical and textural indices to predict geotechnical properties of granites with different degrees of weathering

Bulletin of Engineering Geology and the Environment

Research paper thumbnail of Comparative study of mineralogy and geochemistry of altered felsic rocks in Yazd province

مجله بلورشناسی و کانیشناسی ایران, Mar 1, 2021

Research paper thumbnail of Mineral chemistry and geothermo-barometry based on amphibole of alkali gabbro dykes of Zarigan, northeast of Bafq

Iranian Journal of Crystallography and Mineralogy

Research paper thumbnail of A record of Late Cambrian–Early Ordovician arc magmatism in Yazd block, Central Iran

Arabian Journal of Geosciences

Research paper thumbnail of Petrogenesis of Pliocene-Quaternary Volcanic Rocks in Isfahan Province: Insight on Adakite Magmatism

The Pliocene calc-alkaline volcanic rocks are exposed in two areas in southeast and northwest of ... more The Pliocene calc-alkaline volcanic rocks are exposed in two areas in southeast and northwest of Isfahan and consist of andesites and dacites. Based on geochemical data and multielements pattern, these rocks are medium to high calc-alkaline suite and they show LILE and LREE enriched normalized multi-element patterns, and negative Nb and Ti. Condritenormalized REE patterns display a steep decrease from LREE to HREE without any Eu anomaly. They have higher SiO2 and Sr content and Sr/Y and La/Yb ratios and low MgO, Mg#, Y and Yb contents than the normal calc-alkaline volcanic rocks. These volcanic rocks show adakite characteristics. These features are consistent with ratios obtained from orogenic related volcanic rocks. These rocks may have been produced by partial melting of thickened lower continental crust or slab probably transformed to eclogite or garnet -amphibolite. HREE and Y depleted pattern suggest the existence of garnet and amphibole as a residue in the source.

Research paper thumbnail of Pliocene–Quaternary Adakite volcanism in the Isfahan area, Central Iranian magmatic belt

Neues Jahrbuch für Mineralogie - Abhandlungen, 2009

Abstract: Pliocene-Quaternary calc-alkaline volcanic rocks are exposed in two areas southeast and... more Abstract: Pliocene-Quaternary calc-alkaline volcanic rocks are exposed in two areas southeast and northwest of the Isfahan area in the Urumieh-Dokhtar magmatic belt. These volcanic rocks consist of basaltic andesites, andesites and dacites, which can be found as ...

Research paper thumbnail of Geochemical constraints on the genesis of the volcanic rocks in the southeast of Isfahan area, Iran

Arabian Journal of Geosciences, 2009

Late Miocene-Pliocene to Quaternary calcalkaline lava flows and domes are exposed in southeast of... more Late Miocene-Pliocene to Quaternary calcalkaline lava flows and domes are exposed in southeast of Isfahan in the Urumieh Dokhtar magmatic belt in the Central Iran structural zone. These volcanic rocks have compositions ranging from basaltic andesites, andesites to dacites. Geochemical studies show these rocks are a medium to high K calc-alkaline suite and meta-aluminous. Major element variations are typical for calc-alkaline rocks. The volcanic rocks have SiO 2 contents ranging between 53.8% and 65.3%. Harker diagrams clearly show that the dacitic rocks did not form from the basaltic andesites by normal differentiation processes. They show large ion lithophile elements-and light rare earth elements (LREE)enriched normalized multielement patterns and negative Nb, Ti, Ta, and P. Condrite-normalized REE patterns display a steep decrease from LREE to light rare earth elements without any Eu anomaly. These characteristics are consistent with ratios obtained from subduction-related volcanic rocks and in collision setting. The melting of a heterogeneous source is possible mechanism for their magma genesis, which was enriched in incompatible elements situated at the upper continental lithospheric mantle or lower crust. The geochemical characteristics of these volcanic rocks suggested that these volcanic rocks evolved by contamination of a parental magma derived from metasomatized upper lithospheric mantle and crustal melts.

Research paper thumbnail of Magmatic evolution recorded by phenocrysts in volcanic rocks southeast of Isfahan

Late Miocene–Pliocene calc-alkaline volcanic rocks are exposed southeast of Isfahan in the Urumie... more Late Miocene–Pliocene calc-alkaline volcanic rocks are exposed southeast of Isfahan in the Urumieh-Dokhtar magmatic belt. Volcanic rocks consist of lava flows and domes, chiefly basaltic andesites, andesites and dacites. Minerals in the volcanic rocks exhibit degrees of disequilibrium features. Plagioclase as dominant mineral in these rocks generally displays reverse and oscillatory zoning; sieve or dusty and clear populations, cores are unusually Ca-rich. Hornblende and biotitephenocrysts have reaction rims indicating disequilibrium growth during late stage crystallization. Quartz phenocrysts are corroded and embayed and a few show augite reaction rims. Criteria such as: a) development of sieve textures in plagioclase b) reaction rims in mafic minerals c) reverse zoning and heterogeneity of plagioclase rims d) the resorbed and embayed phenocrysts; support magma mixing as an important process in the evolution of these rocks.

Research paper thumbnail of Early Cambrian highly fractionated granite, Central Iran: Evidence for drifting of northern Gondwana and the evolution of the Proto-Tethys Ocean

Research paper thumbnail of Mineralogical and Geochemical characteristics of the Chah-Shur Clay Deposit, Southeast of Isfahan, Iran

The Chah-Shur clay deposit is located in 150 km southeast of Isfahan. Eocene igneous rocks and Qu... more The Chah-Shur clay deposit is located in 150 km southeast of Isfahan. Eocene igneous rocks and Quaternary deposits cover the area. Eocene volcanic rocks include andesite and tuff. The rocks belong to magmatic activities of Urumieh-Dokhtar magmatic belt. Alteration of the vitric and lithic tuff units has produced the clay deposit. Based on the petrographic studies the main minerals in tuff units are plagioclase, K-feldspar and quartz. The major phases in clay deposit are kaolinite, illite, montmorillonite, quartz, albite and orthoclase. Also, muscovite, chlorite and hematite are as minor phases. The mineralogical studies show an intermediate alteration. The clay deposits can be formed by supergene or hypogene processes; while the combination of both of them can result in the formation of mixed type clay. The geochemical data of Chah-Shur clay deposit show scattering between hypogene and supergene types. The abundance of Fe2O3+TiO2 vs Cr+Nb and Zr vs TiO2, as well asSr+Ba vs Ce+Y+La s...

Research paper thumbnail of Mineralogy, geochemistry, and genesis of the Garak Baghi kaolin deposit in the northwest of Saveh, Iran

The Garak Baghi kaolin deposit is located in Markazi province and in 75 km northwest of Saveh. It... more The Garak Baghi kaolin deposit is located in Markazi province and in 75 km northwest of Saveh. It belongs to the Iranian central structural zone. Eocene-Miocene igneous rocks consist of dacite, andesite, tuff, and other pyroclastic rocks and acidic to intermediate intrusive rocks covered the area. Based on petrographic studies, the main minerals in the volcanic rocks are plagioclase, K-feldspar, and quartz. The tectonic processes have affected the area and formed the main faults and fractures that developed the hydrothermal alteration. Hydrothermal alteration has produced clay deposit. Clay deposits contain kaolinite, illite, and the residual materials of altered feldspar with impurity phase such as gypsum, calcite, anatase, and iron compositions. The quality of clay soils especially near the fault zones has been reduced by iron composition. Geochemical studies show that the rocks are medium-K calc-alkaline and meta-aluminous. Based on chemical index of alteration (CIA) and chemical...

Research paper thumbnail of Petrography and Mineral Chemistry of Volcanic Rocks in Gowris Mountain, South East Isfahan

Research paper thumbnail of Tectonic transition from Ediacaran continental arc to early Cambrian rift in the NE Ardakan region, central Iran: Constraints from geochronology and geochemistry of magmatic rocks

Journal of Asian Earth Sciences

Research paper thumbnail of Crystal size and shape distribution of plagioclase in the basaltic andesites, North of Gavkhouni

Iranian Journal of Crystallography and Mineralogy

Plagioclase is the most abundant mineral in basaltic andesites in the north Gavkhouni. Olivine an... more Plagioclase is the most abundant mineral in basaltic andesites in the north Gavkhouni. Olivine and pyroxene are the other rock forming mineral there. In their 3dimensional shapes, they are unequal and varies between bladed to prolate. Plagioclase sometimes exhibit dusty texture, oscillatory zoning and sinusoid growth. Based on crystal size distribution data, the rate of crystal nucleation of plagioclase varies between 2.77*10-8-3.07*10-8 mm-3 s-1 in 71.78-17.77 years. The results indicate the higher nucleation rate, rapid cooling and a short crystal residence time in the magma chamber. The crystal size distribution diagrams show the high frequency of smaller crystals and the coarsening of the average crystals. However, the presence of two populations of plagioclase indicates the interfering of new magma with the same chemical composition and new crystal population into the magma chamber. This event can increase the volume of the magma chamber pressure and eruption of the magma.