| The Yanshan-Liaoning area is called as the "cradle of geology". It is the first time that the geologist, Wen Wenghao, has put forward the "Yanshan Movement" before 70 years. From then on the Yanshan-Liaoning area had been paying attention by the geologists all over the word because it lies in the particular tectonic background, has the complex structural features, structural units, and the geological history of evolution, particularly large-scale, multi-phrase tectonic movement and magmatic activity took place in the short geological time. After the volcanic eruption of multi-phrase cycle-deformation, filling of basin, crustal uplifting event being studied, this dissertation tries constructing the different degree rhythm of magma activity corresponding with crust-mantle dynamic system, studying the crust-mantle deep processes. Based on the studies on the characteristics of volcanic rhythm, igneous rocks assemblages, temporal and spatial distribution of igneous rocks, tectonic deformation, the author has utilized the methods of petrology, geochemistry, isotopic geology et al. to do research on the above-mentioned geological problems.The yanshan-Liaoning area lies in the crossover zone of the NE-directed West Pacific Ocenic structural system and near SW-directed Paleoz-Asian structural system. To make the yanshanian volcanic tempral and spatial distribution and evolution law clear, study the relationship of the deep crust-mantle processes and the volcanic rocks, the author selects the typical areas, Xishan of Beijing, Duolun of Inner Mongolia, West Liaoning, as the study areas where the volcanic rocks strata are developed. Through the emphasised geological profiles of Yanshanian volcanic strata being surveyed, much field work being done detailly, the small volcanic eruptive units have been defined originally, the levels of volcanic activity rhythm being constructed gradually, as a result, a integrated and systemic rhythm of Yanshanian volcanic acivity has been constructed. Fininaly the rhythm of Yanshanian volcanic acivity in the Yanshan-Liaoning area and Orogenic-deep process is disscussed. Some results are obtained as following.1.To provide the systemic classicification and method about the rhythm of volcanic activity, the rhythm of volcanic activity is divided into 5 levels: gigantic-cycle, megas-cycle, cycle, micro-cycle sub-cycle, rhythm.2. On the basis of study on petrology, volcanic geology, geochemistry, isotopic chronology, antitheses of the regional strata and 4 suits of volcanic rock stratum of the Yanshan-Liaoning area, the rhythm of Yanshanian volcanic activity is divided into 1 gigantic-cycle, 4 cycles, 11 micro-cycles, 24 sub-cycles and many rhythms. In addition, the temporal and spatial evolution and regional contrast of every-level rhythms are discussed.3.Based on the study on classifications of rhythm of volcanic activity and regional contrast, the petrology, mineralogy, geochemistry, and isotopic characteristics of every-level rhythms are discussed. At last the rhythm of Yanshanian volcanic rocks is classified into three series such as alkaline basalt, HKCA, calc-alkaline Shoshonite.4.Based on the study of rock series, assemblage of igneous rock, characteristic of geochemistry, trace effect of isotope, the Yanshanian volcanic rocks of Yanshan-Liaoning area aremainly calc-alkaline series, which should belong to the products of near continental margin of intracontinental tectonic setting. During the Yanshanian phrase, the area is in the condition of contractional background, with multi-staged tectonic reversion.5.Through studying the origin of volcanic rocks and the characteristics of magma evolution, it concludes that there exist 3 originated areas of magma-from mantle, crust, and mantle-crust exchange. The basic magma of Nandaling volcanic rocks of Early Jurassic is derived from Upper mantle; the magma of Tiaojishan volcanic rocks of Mid Jurassic is formed in the contractional tectonic setting, and derived from the transition zone of crust and mantle interaction; the acid...
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