Details

Autor(en) / Beteiligte

• Zhang, Donghai
• Huang, Baochun
• Zhao, Jie
• Meert, Joseph G.
• Zhang, Ye
• Liang, Yalun
• Bai, Qianhui
• Zhou, Tinghong

Titel

Permian Paleogeography of the Eastern CAOB: Paleomagnetic Constraints From Volcanic Rocks in Central Eastern Inner Mongolia, NE China

Ist Teil von

• Journal of geophysical research. Solid earth, 2018-04, Vol.123 (4), p.2559-2582

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2018

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• We carried out a paleomagnetic investigation on Permian volcanic rocks from central eastern Inner Mongolia, NE China, in order to identify the paleoposition of the North China and Songliao‐Xilinhot blocks during Permo‐Carboniferous times and thereby define the spatial‐temporal history of the eastern Paleo‐Asian Ocean (PAO). Two prefolding magnetization components were isolated from the Sanmianjing and Elitu Formations (~283–266 Ma) along the northern margin of North China block (NMNCB) and the Dashizhai Formation (~280 Ma) in the Songliao‐Xilinhot block (SXB). These two results suggest paleolatitudes of ~4.9°N for the SXB and ~22.3°N for the NMNCB. Previously published results are classified according to recently proposed models and evaluated for the influence of inclination shallowing. Combined with earlier multidisciplinary studies, we propose a tentative paleogeographic reconstruction model for the eastern Central Asian Orogenic Belt (CAOB) during the Late Carboniferous to Early Triassic times. Siberia was situated at middle‐high paleolatitudes (~45°–65°N), and the Central Mongolia‐Erguna and South Mongolia‐Xing'an blocks had a middle latitude (~30°–45°N) from the Late Carboniferous to Early Permian. By the Late Permian to Early Triassic (~250 Ma), there was no significant latitudinal difference between the eastern CAOB blocks. Final closure of the eastern PAO along both the Hegenshan‐Heihe and Solonker sutures took place followed by the formation of Cinamuria. Key Points The SXB was situated at an equatorial paleolatitude (~2.9°S–4.9°N) during Late Carboniferous to Early Permian times (~320–280 Ma) The NCB was located at ~22.3° ± 4.1°N during late Early Permian to Middle Permian times (Kungurian‐Wordian, ~283–266 Ma) Final closure of the Paleo‐Asian Ocean took place during Late Permian‐Early Triassic times (~250 Ma)