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古气候模拟已经成为白垩纪古气候研究中不可替代的技术手段。但是目前中国白垩纪陆相古气候模拟的一些关键边界条件尚未完全确定。通过白垩纪沉积记录对中国大陆白垩纪古海陆边界和古地形做出约束。早白垩世,新疆西南部喀喇昆仑地区可能存在喀喇昆仑海湾,在东北松辽盆地东侧有乌苏里湾;晚白垩世,受全球海平面上升的影响,特提斯海向北延伸,新疆西部地区存在塔西南海湾和喀喇昆仑海湾;而受燕山运动的影响,乌苏里湾向东退出松辽盆地,影响变小。在古地形方面,认为东北大兴安岭,西北天山、祁连山、昆仑山等山脉,西南云贵高原、川西高原、横断山,秦岭—大别山在白垩纪时均已形成并隆升到一定高度;指出“东部高原”和“沿岸山脉”的存在与否可能对白垩纪古气候状况产生深远的影响。此外,还讨论了沉积记录与古气候模拟结果的对比、验证对中国大陆白垩纪古气候重建的重要作用。
Paleoclimate modeling has become an irreplaceable technical means in the study of paleoclimate in the Cretaceous. However, at present, some key boundary conditions of the continental paleoclimate simulation of the Cretaceous in China have not yet been completely determined. Through the Cretaceous sedimentary records, the Cretaceous ancient sea-land boundary and palaeogeography in the Chinese mainland are restrained. Early Cretaceous, the Karakoram region in southwestern Xinjiang may have Karakoram Bay, northeast Songliao Basin Wusuli Bay; Late Cretaceous, the global sea level rise, the Tethys sea extends northward In the western part of Xinjiang, there are the Tashan Gulf and Karakoram bays. Due to the Yanshan movement, the Ussuri Bay will exit the Songliao Basin to the east with less impact. In ancient terrain, it is considered that the mountains of Daxinganling, Northwest Tianshan, Qilian Mountains and Kunlun Mountains, the Yunnan-Guizhou Plateau, the western Sichuan Plateau, the Hengduan Mountains and the Qinling-Dabie Mountains have been formed and uplifted to a certain height during the Cretaceous. The existence of the plateau and coastal mountains may have a far-reaching impact on the paleoclimatic conditions of the Cretaceous. In addition, the comparison between sedimentary records and paleoclimate simulation results is also discussed to verify the important role of Cretaceous paleoclimate reconstruction in mainland China.