کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4691752 1636748 2015 23 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A paleolatitude reconstruction of the South Armenian Block (Lesser Caucasus) for the Late Cretaceous: Constraints on the Tethyan realm
ترجمه فارسی عنوان
بازسازی سلسله مراتع بلوک ارمنستان جنوبی (قفقاز کم) برای کرتاسه پسین: محدودیت هایی بر قلمرو تتیان
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


• Six sites in Paleozoic sedimentary SAB rocks have (likely) been remagnetized.
• Data from Upper Cretaceous rocks were corrected for inclination shallowing.
• Maximum ~ 1000 km at 85 Ma between SAB and Eurasia when comparing SAB data to latitude vs. age curves (derived from pole path).
• Maximum ~ 350 km distance (at ~ 85–80 Ma) by direct comparison of SAB and Eurasia data.
• Clockwise rotations of ~ 85–80 Ma old strata are in line with earlier studies.

The continental South Armenian Block – part of the Anatolide–Tauride South Armenian microplate – of Gondwana origin rifted from the African margin after the Triassic and collided with the Eurasian margin after the Late Cretaceous. During the Late Cretaceous, two northward dipping subduction zones were simultaneously active in the northern Neo-Tethys between the South Armenian Block in the south and the Eurasian margin in the north: oceanic subduction took place below the continental Eurasian margin and intra-oceanic subduction resulted in ophiolite obduction onto the South Armenian Block in the Late Cretaceous.The paleolatitude position of the South Armenian Block before its collision with Eurasia within paleogeographic reconstructions is poorly determined and limited to one study. This earlier study places the South Armenian Block at the African margin in the Early Jurassic. To reconstruct the paleolatitude history of the South Armenian Block, we sampled Upper Devonian–Permian and Cretaceous sedimentary rocks in Armenia. The sampled Paleozoic rocks have likely been remagnetized. Results from two out of three sites sampled in Upper Cretaceous strata pass fold tests and probably all three carry a primary paleomagnetic signal. The sampled sedimentary rocks were potentially affected by inclination shallowing. Therefore, two sites that consist of a large number of samples (> 100) were corrected for inclination shallowing using the elongation/inclination method.These are the first paleomagnetic data that quantify the South Armenian Block's position in the Tethys ocean between post-Triassic rifting from the African margin and post-Cretaceous collision with Eurasia. A locality sampled in Lower Campanian Eurasian margin sedimentary rocks and corrected for inclination shallowing, confirms that the corresponding paleolatitude falls on the Eurasian paleolatitude curve. The north–south distance between the South Armenian Block and the Eurasian margin just after Coniacian–Santonian ophiolite obduction was at most 1000 km.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tectonophysics - Volumes 644–645, 16 March 2015, Pages 197–219
نویسندگان
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