By the measurement of the wind directional indicator of theCretaceous desert in Ordos Basin, the regularity of the paleoprevailing wind directions and pattern of the paleowind belts are revealed. It is considered that...By the measurement of the wind directional indicator of theCretaceous desert in Ordos Basin, the regularity of the paleoprevailing wind directions and pattern of the paleowind belts are revealed. It is considered that the desert was controlled by a planetary wind system. In the early stage, the subtropical high pressure zone drifted south and northwards with short cycles, resulting in the alternation of westerlies and northeast trades; in the late stage, the subtropical high pressure zone drifted southwards with a long cycle, placing the desert under the westerly belt and making the desert completely controlled by the westerly belt. The reconstruction of the paleowind belts has provided the evidence of the general circulation of the atmosphere for the pattern of the circulation before the uplift of the Tibetan Plateau.展开更多
The Tibetan Plateau is a key factor for the pattern of the general circulation of the atmosphere (GCA) in eastern Asia. The pattern of the GCA after the uplift of the plateau is well known, while the pattern of the GC...The Tibetan Plateau is a key factor for the pattern of the general circulation of the atmosphere (GCA) in eastern Asia. The pattern of the GCA after the uplift of the plateau is well known, while the pattern of the GCA before the uplift of the plateau is lack of direct evidences. Based on the knowability of desert, a section recording wind directions across the Cretaceous northern hemisphere mid-low latitude desert belt is measured and the pattern of the GCA in the Cretaceous is revealed. The result shows that the eastern Asia was really controlled by the planetary circulation before the uplift of the plateau, i.e. westerlies in the north and northeast trades in the south. The convert belt between westerlies and trades had drifted northwards and southwards. The possibility of existence of paleo-monsoon is also dealt with and a possibly imposed paleo-monsoon is suggested.展开更多
基金The field work has been guided by Prof. Qi Hua from Xi'an Institute of Geology and Mineral Resources and the indoor work has been supervised by Academician Liu Baojun and Prof. Pan Guitang, Director of Chengdu Institute of Geology and Mineral Resources.
文摘By the measurement of the wind directional indicator of theCretaceous desert in Ordos Basin, the regularity of the paleoprevailing wind directions and pattern of the paleowind belts are revealed. It is considered that the desert was controlled by a planetary wind system. In the early stage, the subtropical high pressure zone drifted south and northwards with short cycles, resulting in the alternation of westerlies and northeast trades; in the late stage, the subtropical high pressure zone drifted southwards with a long cycle, placing the desert under the westerly belt and making the desert completely controlled by the westerly belt. The reconstruction of the paleowind belts has provided the evidence of the general circulation of the atmosphere for the pattern of the circulation before the uplift of the Tibetan Plateau.
基金the National Natural Science Foundation of China (Grant No. 49572113).
文摘The Tibetan Plateau is a key factor for the pattern of the general circulation of the atmosphere (GCA) in eastern Asia. The pattern of the GCA after the uplift of the plateau is well known, while the pattern of the GCA before the uplift of the plateau is lack of direct evidences. Based on the knowability of desert, a section recording wind directions across the Cretaceous northern hemisphere mid-low latitude desert belt is measured and the pattern of the GCA in the Cretaceous is revealed. The result shows that the eastern Asia was really controlled by the planetary circulation before the uplift of the plateau, i.e. westerlies in the north and northeast trades in the south. The convert belt between westerlies and trades had drifted northwards and southwards. The possibility of existence of paleo-monsoon is also dealt with and a possibly imposed paleo-monsoon is suggested.
