四川盆地白垩纪沙漠风向变化规律及其意义

本文报道了四川盆地白垩纪沙漠古风向测量结果，总结了风向变化的规律。认为该浙江省早期处于副热高压带地区的西北和东北切变带（ｄｉｖｅｒｇｅｎｔ ｌａｔｉｔｕｄｅｓ ｏｆ ｗｅｓｔｅｒｌｙ ｗｉｎｄｓ ａｎｄ ｎｏｒｔｈｅａｓｔｅｒｌｙ ｔｒａｄｅ ｗｉｎｄｓ）。随着气候的波动，该切变带发生了短周期的南北向漂变，造成西风与东北信风交替现象。

The variations of palaeowind direction of the Cretaceous desert in the Sichuan Basin and their significance

The present paper deals with the measurements and variations in palaeowind direction of the Cretaceous desert in the Sichuan Basin. The desert was in the divergent latitudes of westerly winds and northeasterly trade winds in the subtropical high pressure belts during the early stage of the desert. The short period NS drifts of the divergent latitude in response to the climatic fluctuations are responsible for the alternation of westerly winds and northeasterly trade winds. Till the late stage of the desert, the divergent latitudes was drifted southwards due to the lond period climatic fluctuations and thus the whole desert was within the extent of the westerly winds. Finally the climatic changes in East Asia from the Cretaceous onwards are also discussed. The authors contend that planetary circulations and dry climates once prevailed over East Asia prior to the uplifting of the Qinghai Xizang Plateau. This situation, however, has been changed since the uplifting of the plateau, e.g. from planetary circulation patterns into monsoon circulation and from dry climate into humid climate. The measurements of the palaeowind direction of the Sichuan Basin during the Cretaceous have supplied the geological data on the atmosphere circulations in East Asia prior to the uplifting of the Qinghai Xizang Plateau, and thus are of great scientific importance.