Li Siguang has been engaged in the study of China (Ting) fossils and Quaternary glaciers. For a long time, the world is full of fallacies about the Quaternary metamorphic glaciers in China. 192 1 year, he first discovered Quaternary glacial remains in the eastern foot of Taihang Mountain and Datong Basin. In 1930s, various kinds of ice erosion, moraine landforms and moraines were found in Lushan, Huangshan, Jiuhua Mountain and Tianmu Mountain in the middle and lower reaches of the Yangtze River, and the classic "Lushan Ice Age" was written, which divided four glacial periods and three interglacial periods, laying a foundation for the study of Quaternary glaciology in China. And has been positively evaluated by peers at home and abroad. In the 1940s, he visited eastern Sichuan, western Hubei, western Hunan, northern Guangxi and Guizhou Plateau, and published a series of works on glacial remains and ice age division. In 1950s, he identified many glacial remains in the Xishan area of Beijing, and personally planned and presided over the study of Quaternary glaciers in China in the early 1960s.
Throughout his life, Li Siguang advocated studying the occurrence, development and combination law of geological structures from the mechanical point of view, believing that all kinds of structural traces are the result of in-situ stress activities, and established the concept of "structural system" and geomechanics school. Li Siguang dispelled the fog of "China's theory of poor oil" with geomechanics theory, guided the petroleum geological survey in China, and made great contributions to the discovery of oil fields in eastern China. China is a country with many earthquakes, and Li Siguang has done a lot of pioneering work for earthquake geology and earthquake prediction. In his later years, Li Siguang also did a lot of work for the development and utilization of geothermal energy in China. He is the author of Main Causes of Image Changes on the Earth's Surface, Tingzhi in Northern China, Geology of China, Lushan Mountain in the Ice Age, Introduction to Geomechanics, Seismogeology, Anthology of Astronomy, Geology and Paleontology, etc.
Geology: the study of the materials and crustal structure that make up the earth, with the purpose of exploring the formation and development of the earth.
Glacier: In high mountains or polar regions, snow becomes ice due to its own pressure (or snow freezes into ice due to infiltration and melting), and then moves along the inclined direction of the ground due to gravity. This moving mass of ice is called a glacier.
Qinling Mountains: It is located in the south-central part of Shaanxi Province. East-west trend. It is the watershed between the Yellow River and the Yangtze River, and it is also a part of the geographical dividing line between north and south of China. Taibai Mountain, the main peak, is 3 767 meters above sea level.
Yangtze river basin: the Yangtze river basin refers to the catchment area of the main tributaries of the Yangtze river, that is, the catchment area, commonly known as the basin area, which is 654.38+0.8 million square kilometers, accounting for 654.38+0.8% of China's land area. Including all or part of two autonomous regions (Tibet and Guangxi) in 15 provinces (Qinghai, Yunnan, Guizhou, Sichuan, Gansu, Shaanxi, Henan, Hubei, Hunan, Jiangxi, Anhui, Jiangsu, Zhejiang, Guangdong and Fujian) 1 municipality directly under the central government (Shanghai). The natural dividing line of the Yangtze River Basin is bounded by Bayan Kara, Xiqiao Mountain, Minshan Mountain, Qinling Mountain, Funiu Mountain, Tongbai Mountain, Dabie Mountain and Huaiyang Mountain in the north, Yunling Mountain, Jizu Mountain in Dali, Bidirectional Mountain in Central Yunnan, Wumeng Mountain, Miaoling Mountain and Nanling Mountain in the south, and the Lancang River, Yuanjiang (Red River) and Pearl River Basin in Hengduan Mountains. The southeast is bounded by Wuyi Mountain, Twelve Mountains, Huangshan Mountain, Tianmu Mountain and Fujian-Zhejiang water system. The northern part of the source area of the Yangtze River is bounded by Kunlun Mountain and the internal water system of Qaidam Basin. The two parts are bounded by the Kekexili Mountain, Wulan Wula Mountain, Zuerken Wula Mountain, Ga (G·m 4) Chadi Rugang Snow Mountain Group and the internal water system of Qiangtang in northern Tibet; The southern part is bounded by Tanggula Mountains and Nujiang River Basin; The northern part of the Yangtze River Delta, with flat terrain and dense water networks, is difficult to be separated from the Huaihe River Basin, usually bounded by Jiangdu-Pincha Highway near the Toarey Yang Canal. The southern part of the Yangtze River Delta is bounded by Hangjiahu Plain and the hills on the south side of Qiantang River Basin. The outline of the Yangtze River basin is like a water chestnut with narrow ends and wide middle, ranging from 9033' east longitude to 122 "25' north latitude from 24" 30' to 35 "45'. The distance from east to west is over 3,000 kilometers, and the width from north to south is about 1000 kilometers, except for the source of the Yangtze River and the Yangtze River Delta. Because most of the water in the Huaihe River also flows into the Yangtze River through the Grand Canal, in a sense, the Huaihe River is also a tributary of the Yangtze River. If the Huaihe River Basin is added, the area of the Yangtze River Basin is close to 2 million square kilometers.
Quaternary Glaciers: About 2.5 million years ago. During this period, many glaciation occurred widely in high latitudes, and the climate was extremely cold. People call the glaciers of this era Quaternary glaciers.
Trace: a trace left by something ancient or old.