Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone
The Bulfat Igneous Complex comprises the Bulfat and Walash groups and is situated in the Zagros Suture Zone, in the junction of Arabian and Eurasian plates. Zircon U-Pb data indicat an age of 63.7 ± 1.5 Ma for the trondhjemite rocks within the Bulfat group. Walash group is primarily composed of basa...
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MDPI AG
2023-10-01
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| Series: | Minerals |
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| Online Access: | https://www.mdpi.com/2075-163X/13/11/1367 |
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| author | Yousif Mohammad Kurda Abdulla Hossein Azizi |
| author_facet | Yousif Mohammad Kurda Abdulla Hossein Azizi |
| author_sort | Yousif Mohammad |
| collection | DOAJ |
| description | The Bulfat Igneous Complex comprises the Bulfat and Walash groups and is situated in the Zagros Suture Zone, in the junction of Arabian and Eurasian plates. Zircon U-Pb data indicat an age of 63.7 ± 1.5 Ma for the trondhjemite rocks within the Bulfat group. Walash group is primarily composed of basalt to andesite rocks, interbedded with sedimentary rocks. Zircon U-Pb dating yields an age of 69.7 ± 2.7 Ma for the Walash group. Whole rocks chemistry shows that the Bulfat rocks have affinity to MORB and calc alkaline series but Walsh are mainly plot in the calc alkaline field. Whole rocks Sr-Nd isotope ratios show that the <sup>143</sup>Nd/<sup>144</sup>Nd (i) changes from 0.51243 to 0.52189 and 87Sr/86Sr(i) ratios vary from 0.70345 to 0.7086. The calculated εNd(t) values, based on the CHUR, yield predominantly high positive values ranging from +6 to +8 for most samples. However, a few samples exhibit lower values (+2 to +3). Our data suggest that the interaction between lithospheric (depleted mantle, MORB-Like) and asthenospheric mantle (OIB-like) melts significantly controlled the magmatic evolution of the Bulfat group. The strong positive εNd(t) values (ranging from +6 to +8) align more consistently with a highly depleted lithospheric mantle source for the Walsh group. Therefore, the gradual transition from an arc signature at 70 Ma to a MORB signature around 63 Ma, occurred over a relatively short period of about 10 million years, and indicates the presence of an arc and back-arc system in the Neotethys ocean before the collision of the Arabian and Iran plates during the Cenozoic. |
| first_indexed | 2024-03-09T16:34:53Z |
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| id | doaj.art-0819e5cb13574fcd80d021957baf2a34 |
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| language | English |
| last_indexed | 2024-03-09T16:34:53Z |
| publishDate | 2023-10-01 |
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| record_format | Article |
| series | Minerals |
| spelling | doaj.art-0819e5cb13574fcd80d021957baf2a342023-11-24T14:57:26ZengMDPI AGMinerals2075-163X2023-10-011311136710.3390/min13111367Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture ZoneYousif Mohammad0Kurda Abdulla1Hossein Azizi2Department of Geology, College of Science, University of Sulaimani, Sulaymaniyah 46011, IraqDepartment of Geology, College of Science, University of Sulaimani, Sulaymaniyah 46011, IraqDepartment of Mining Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj 66177-15175, IranThe Bulfat Igneous Complex comprises the Bulfat and Walash groups and is situated in the Zagros Suture Zone, in the junction of Arabian and Eurasian plates. Zircon U-Pb data indicat an age of 63.7 ± 1.5 Ma for the trondhjemite rocks within the Bulfat group. Walash group is primarily composed of basalt to andesite rocks, interbedded with sedimentary rocks. Zircon U-Pb dating yields an age of 69.7 ± 2.7 Ma for the Walash group. Whole rocks chemistry shows that the Bulfat rocks have affinity to MORB and calc alkaline series but Walsh are mainly plot in the calc alkaline field. Whole rocks Sr-Nd isotope ratios show that the <sup>143</sup>Nd/<sup>144</sup>Nd (i) changes from 0.51243 to 0.52189 and 87Sr/86Sr(i) ratios vary from 0.70345 to 0.7086. The calculated εNd(t) values, based on the CHUR, yield predominantly high positive values ranging from +6 to +8 for most samples. However, a few samples exhibit lower values (+2 to +3). Our data suggest that the interaction between lithospheric (depleted mantle, MORB-Like) and asthenospheric mantle (OIB-like) melts significantly controlled the magmatic evolution of the Bulfat group. The strong positive εNd(t) values (ranging from +6 to +8) align more consistently with a highly depleted lithospheric mantle source for the Walsh group. Therefore, the gradual transition from an arc signature at 70 Ma to a MORB signature around 63 Ma, occurred over a relatively short period of about 10 million years, and indicates the presence of an arc and back-arc system in the Neotethys ocean before the collision of the Arabian and Iran plates during the Cenozoic.https://www.mdpi.com/2075-163X/13/11/1367island arcZagros Sutures Zoneoceanic arc-back-arc systemcollision zoneIraq |
| spellingShingle | Yousif Mohammad Kurda Abdulla Hossein Azizi Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone Minerals island arc Zagros Sutures Zone oceanic arc-back-arc system collision zone Iraq |
| title | Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone |
| title_full | Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone |
| title_fullStr | Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone |
| title_full_unstemmed | Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone |
| title_short | Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone |
| title_sort | late cretaceous paleocene arc and back arc system in the neotethys ocean zagros suture zone |
| topic | island arc Zagros Sutures Zone oceanic arc-back-arc system collision zone Iraq |
| url | https://www.mdpi.com/2075-163X/13/11/1367 |
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