中国古地理图研制发展的脉络与前景

早期的中国古地理图,是在地球大陆固定概念的基础上着重于海陆分布、形态、变化特征的描绘。后来注意了全球构造的“活动论”与历史演化的“阶段论”相结合,开始了多种类型图件的表达,再后通过板块构造、古地磁学资料的更多积累,预期下一代的中国古地理图将呈现各地质时期的古地理单元恢复到原始位置进行描绘的前景。从第四纪大冰期冰川作用的深入研究,使其极大影响下的各种古地理事件及古地理单元的形成、分布和变化得到深入的了解和更合理的解释,可编制出该时期新一代更符合实际的中国古地理图来。

THE COURSE AND PROSPECT OF THE STUDES ON THE PALEOGEOGRAPHIC MAP OF CHINA

Paleogeographic map is a map that shows the reconstructed physical geography of a particular time in the geological history for a certain region or a world-wide scope, including the information of the aspect, feature and the changes of various kinds of paleogeographic forms and events.The development in the early stage on paleogeographic map compilation researches in China stressed the depletion on the distribution and the changes of lands and seas on the basis of guiding views that the position of oceans and continents on the earth have no large horizontal displacement during the geological history. In the later time, the attention was initially paied to the integrating With the idea of "Mobilism" with respect to global tectonic, and the idea of "Development Stages" with respect to the history of crustal evolution to make the indictation of more different paleogeogrphic features with various kinds of maps.This process was marked in the following records. At first, several sketch maps mainly show the distribution of lands and seas of a few geological periods of China.Which imparted significant rudimentary knowledge to the successors, in the "Stratigraphy of China"1] by A. W. Grabau. Another one later, which played an important examplary role, was those paleogeographico-tectonic maps of Cambrian,Caledonian-Devonian, Variscan-Permian, Yanshanian-Cretaceous, and Himalayan times of China in the classical monograph "On Major Tectonic Forms of China"2].Later on, the first systematic and complete set of paleogeographic maps from Sinian to Triassic periods in the "Paleogeographic Atlas of China"3], which initiated a new prototype in the P. R. China. Then the paleogeographic maps of the distribution, the changes of seas and lands, and marine lithofacies atlas, were compiled mainly for the purpose of oil and gas exploration, in "The Changes of hands and Seas, Marine Sedimentary Factes and Hydrocarbons"4] In the same time, the paleogeographic maps of China in "Paleogeography-the Physical Geography of China"5], showing the distribution of lands and seas and their changes caused by tectonic movements in the geological time, were compiled on the basis of a leading thought of the "Diastrophism".The comprehensive "Atlas of the Paleogeography of China"6] was composed of a series of more systematic and completed paleogeographic maps and other kinds of related maps. It began upon the "Mobilism' with respect to global tetonics followed in the compilation of maps. Treatment of marking tectonic junctures and subduction zones on paleogeographic maps was made under the condition of insufficiant paleogeographic and other related data, and various kinds of maps such as sketch maps of biogeography and small scal maps showing the climate belts were included.And then, four lithofacies-paleogeographic maps on time units of "Epoch" and "Age", specialized in a period-Sinian, were given in "The Sinian System of China"7].These are the most detailed set of Sinian paleogeographic maps so far.The appearance of such a prospect Will be expected through more accumulation and appliacation of data obtained from the investigation of plate tectonics and paleomagnetism, that the paleogeographic depletion will be taken on those paleogeographic units to be returned to the original positions in each geological period in the compilation researches of paleogeographic maps of China in next stage. The glaciation of Quaternary glacial period is a greatly important paleogeographic event.More further understanding and explanation on the origin, distribution and the changes of various related paleogeographic events and units seriously affected by the great glaciation will be gained through a thorough deepgoing investigation on Quaternary glacial process. From then on, new type of paleogeographic maps of China with higher quality in that period will be compiled in the coming years.