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In conclusion, the chronological classification should base upon the followiag three bases:1. Cycle of Sedimentation2. Diastrophism3. Faunal AssemblageThe old classification mainly based upon palaeontological ground is not satisfactory, while the new classification of Grabau based on pulsation theory alone is also impracticable. It is really difficult to separate the transgressive series from the regressive series as the latter is usually poorly represented or even replaced by an erosional interval. I would use the cycle of sedimentation instead of the pulsation theory as one of the important bases. It is obvious that every Palaeozoic system of China repre sents one major-cycle, except the Permian which was affected by the Tungwu disturbance at the end of Yangsin epoch and comprises two cycles of sedimentation.It is also true that all the Palaeozoic systems of China are distinctly separated by breaks caused either by orogenic movement or epirogenic uplifting. I would still take Taconian (Lower Cambrian of the old classification) for the first system of the Palaeozoic of China because of the occurrence of the abundant ancient life in the Taconian rocks, although no angular contact has been found between the Taconian and its underlying Sinian.More recently J. S. Lee has found a hiatus between the marine Permian (top of Palaeozoic) and its overlying marine Triassic (base of Mesozoic) at Talung, Kuangsi. An unconformity between the Triassic and the Changhsing limestone was also reported from Chekiang.As to the index fossils, we should pay great attention to the range of the families of a certain group, the assemblage of each zone and particularly to the anctent ocean or the geosyncline from which they were originated.Two-fold or three-fold division of each system is better made by means of the faunal contents and the lithological characters.Of eight Chinese Palaeozoic systems five systems admit of three-fold division, but only three-the Cambrian, the Carboniferous and the Permian—are two-fold systems. Thus the present classification of Palaeozoic rocks of China would be as follows:Triassic (Mesozoic)——long break——8. Permian Tungwu movement (Lee) Yunna uplifting (Hsieh and Kao)7. Carboniferous Huainan uplifting (Lee)6. Dinantian Liukiang movement (Chu) (Hercynian)5. Devonian Kuangsi movement (Ting) (Caledonian)4. Silurian Ichang uplifting (Sun)3. Ordovician Yehli uplifting (Sun)2. Cambrian Yuakuei uplifting (Sun)1. Taconian——long break——Sinian (Pre-Palaeozoic)
In conclusion, the chronological classification should base upon the followiag three bases: 1. Cycle of Sedimentation 2. Diastrophism 3. Faunal Assemblage The classification of old based upon palaeontological ground is not satisfactory, while the new classification of Grabau based on pulsation theory alone is also impracticable. It is really difficult to separate the transgressive series from the regressive series as the latter is usually poorly represented or even replaced by an erosional interval. I would use the cycle of sedimentation instead of the pulsation theory as one of the important bases. It is obvious that every Palaeozoic system of China represents one major-cycle, except the Permian which was affected by the Tungwu disturbance at the end of Yangsin epoch and comprises two cycles of sedimentation. It is also true that all the Palaeozoic systems of China are distinctly separated by breaks caused either by orogenic movement or epirogenic uplifting. I would still take Taconia n (Lower Cambrian of the old classification) for the first system of the Palaeozoic of China because of the occurrence of the abundant ancient life in the Taconian rocks, although no angular contact has been found between the Taconian and its underlying Sinian. More recently JS Lee has found a hiatus between the marine Permian (top of Palaeozoic) and its overlying marine Triassic (base of Mesozoic) at Talung, Kuangsi. An unconformity between the Triassic and the Changhsing limestone was also reported from Chekiang. As to the index fossils, we should pay great attention to the range of the families of a certain group, the assemblage of each zone and particularly to the anctent ocean or the geosyncline from where they were originated. Two-fold or three-fold division of each system is better made by means of the faunal contents and the lithological characters. Eight of Palaeozoic systems five systems admit of three-fold division, but only three-the Cambrian, the Carboniferous andThe Permian-are two-fold systems. Thus the present classification of Palaeozoic rocks of China would be as follows: Triassic (Mesozoic) - long break - 8. Permian Tungwu movement (Lee) Yunna uplifting (Hsieh and Kao) (Sun) 2. Cambrian Yuakuei uplifting (Sun) 2. Dinhualian Liukiang movement (Chu) (Hercynian) 5. Devonian Kuangsi movement (Ting) (Caledonian) 4. Silurian Ichang uplifting (Sun) Sun) 1. Taconian - long break - Sinian (Pre-Palaeozoic)