Geochemistry and source characteristics of Dehsard mafic volcanic rocks in the  southeast of the Sanandaj–Sirjan zone, Iran: implications for the evolution of the Neo-Tethys Ocean

Mohammadali NAZEMEI; Mohsen ARVIN; Sara DARGAHI

Makale detayları

Geochemistry and source characteristics of Dehsard mafic volcanic rocks in the southeast of the Sanandaj–Sirjan zone, Iran: implications for the evolution of the Neo-Tethys Ocean

Yazarlar:

Mohammadali NAZEMEI | Mohsen ARVIN | Sara DARGAHI

Yayıncı:

TUBITAK

Ana Başlıklar:

Uygulamalı fizik

Dergi:

Turkish Journal of Earth Sciences 2018 Vol.27 Issue 4, pp.249-268

Belge Tipi:

Makale

Yayın Tarihi:

7/2018

Belge Dili:

İngilizce

Document ID (Org No.):

2000731143

Sıklık:

İki Aylık

eISSN:

1303-619X

pISSN:

1300-0985

Özet:

 

 
                         The Late Jurassic-Early Cretaceous Dehsard mafic volcanic rocks crop out in the southeastern Sanandaj-Sirjan Zone (SSZ),
composed primarily of basalts and basaltic andesite with subordinate dolerite. They are influenced to some degree by hydrothermal
alteration under zeolite-greenschist facies. Using fairly immobile trace elements, the mafic volcanic rocks show subalkaline (tholeiitic)
affinities. They commonly have similar designs with somewhat strong enrichment in light rare earth elements (LREEs) and large ion
lithophile elements (LILEs) and depletion in high field strength elements (HFSEs; e.g., Nb, Ta, Ti) and nearly flat heavy rare earth
element (HREE) patterns. The negligible or absence of negative Eu anomalies indicate that plagioclase played an insignificant role
during magma evolution. The low La/Nb (1.03-2.31) and Nb/Y (0.12-0.46) ratios, relatively high Zr/Y (4.03-8.18) and Th/Ta (2.25-
9.64) ratios, steady enhanced normalized patterns, and moderate La/Nb ratios hint at an island arc and most likely a back-arc basin
environment for the formation of Dehsard mafic volcanic rocks. The arc magma resulted from partial melting of depleted mantle source
that experienced assimilation and fractional crystallization and was enhanced by melts of subducted sediments or contribution of slabderived
fluids in an intraoceanic subduction environment in the Neo-Tethyan Ocean. Therefore, the presence of an island arc setting
(Dehsard island arc) must be investigated in the south of the SSZ prior to the Late Jurassic-Early Cretaceous as the Neo-Tethys oceanic
crust was subducting north beneath the southern margin of the Central Iranian Microcontinents. The later collision of the arc with SSZ
led to tectonic proximity of the Dehsard mafic volcanic rocks to SSZ components.

Makale detayları

Geochemistry and source characteristics of Dehsard mafic volcanic rocks in the southeast of the Sanandaj–Sirjan zone, Iran: implications for the evolution of the Neo-Tethys Ocean

Yazarlar: Mohammadali NAZEMEI | Mohsen ARVIN | Sara DARGAHI

Yayıncı: TUBITAK

Ana Başlıklar: Uygulamalı fizik

Dergi: Turkish Journal of Earth Sciences 2018 Vol.27 Issue 4, pp.249-268

Belge Tipi: Makale

Yayın Tarihi: 7/2018

Belge Dili: İngilizce

Document ID (Org No.): 2000731143

Sıklık: İki Aylık

eISSN: 1303-619X

pISSN: 1300-0985

Sayı

Yazarlar:

Mohammadali NAZEMEI | Mohsen ARVIN | Sara DARGAHI

Yayıncı:

TUBITAK

Ana Başlıklar:

Uygulamalı fizik

Dergi:

Turkish Journal of Earth Sciences 2018 Vol.27 Issue 4, pp.249-268

Belge Tipi:

Makale

Yayın Tarihi:

7/2018

Belge Dili:

İngilizce

Document ID (Org No.):

2000731143

Sıklık:

İki Aylık

eISSN:

1303-619X

pISSN:

1300-0985