| It has been detailedly studied about three-dimensional shape and internal structure of deposital system in the continental basin. But lacking of high-resolutional study on confirming age according to the genetic unit, and also lacking of quantificationally study on evolutive periodicity and velocity of deposital system and its internal structural unit. The paper has chosen Shen95 Block of LiaoHe Basin and ascertained the evolutive velocity of structural unit of deposital system. The studied area is characteristic of the large denseness of well net and the small distance between wells. And there are many wells whose cores have been taken more 97%. Which offers good qualifications for analyzing of the three-dimensional structural and evolution of deposital system. Additionally, the volcano action of the basin offered accurate for the paper according to isotope age measured by former depending on volcano rock.The paper has chosen Well Jing43-67 as the main object which lied on the frontal delta and the front of delta, and the cores were taken continuously. Which assures it is intact of the studied strata. For making sure the precision, the paper has also chosen Well Jing37-69 as complementary well. About 100 samples were chosen to experiment for magnetic strata. Based on the multi-shelves thermal demagnetization, magnetic test, directional analysis, the paper has drawn the paleo-latitude map and contrasted it with international standard polarity pole on the basis of the volcano rock age. Which shows the studied strata includes the whole polarity period of C18n and C17n ,and the partial polarity period of C19n and C16n. It has experienced 4.916Ma in the long 135-meter core. The C18n includes 41.257-38.426 Ma, and the C17n includes 38.426-36.341 Ma. The result of magnetic test shows it very similar of the magnetic strata of Eogene among LiaoHe basin, JiYang basin and ChaiTaMu basin.Based on the magnetic strata of Well Jing43-67, the paper has also studied the three-dimensional structure and evolutive velocity. By looking into the cores, analyzing of granularity and ichno-fossils, the paper has ascertained the basin as a normal fluvial delta deposital system, which amends the former view that believed the basin should be a fan-delta system. The deposital system was composed of three whole deposital association including delta plain, the front of delta and frontal delta. And the delta genetic unit includes distributary channel, distributary bay, small lake of delta plain, swamp, distributary estuary bar, frontal delta mud and sandy density flow and so on. The fluvial system is composed of channel, channel side and flooding basin. And the fluvial genetic unit includes point bar, the bottom of channel, bursted fan, bursted channel, natural bank, over-bank deposits, small lake of flooding plain and swamp and so on. According to deposital system, deposital association and genetic faces, the paper has drawn the vertical evolutive map of typical Well Jing43-67.The paper has worked out the deposital velocity of every magnetic strata unit combining the vertically evolutive map with the magnetic strata age experimented. The average deposital velocity of the basin was 7.3mm/ka during C18n period and 62.77mm/ka during C17n period.And the most deposital velocity was 220.2mm/ka during C17.3n sub-period, which mainly occurred at the unloaded area in the front of the delta.Based on the deposital velocity of the magnetic strata unit, the paper has worked out the velocity of the genetic unit of the basin utilizing the vertically evolutive map. The results indicate it very different of the deposital velocity among different genetic faces. Even if the same genetic face, the velocity is very different because of different location. For example, the velocity of the vicinity and beyond of estuary bar is respectively 238.33mm/ka and 0.89 mm/ka. The paper has also related the deposital velocity of delta with quite deep lake of Eogene of JiYang basin and the Okinawa trough of Quaternary and contemporarily shore. Which s...
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