LATE TRIASSIC MAGMATIC ACTIVITIES IN RELATION TO PLATE TECTONICS OF THE EASTERN PART OF JILIN AND HEILONGJIANG PROVINCES, NORTHEAST CHINA
吉黑东部晚三叠世岩浆活动及其与板块构造的关系

The eastern part of Jilin and Heilonjiang Provinces, Northeast China, is of the Circum-Pacific Tectonic Region. Study of the regional geology indicates that this region was tectonically rather active, specially in the realm of magmatism, in its initial stage (Late Triassic) of development.At the beginning of the Mesozoic, the Nadanhadaling in the first was splited and separated from the ancient continental margin, resulting in a margin sea basin with the develoment of ocean crust; this was followed by the emplacement of ophiolite in the Late Triassic under the effect of farther subduction of the Kula Plate. Finaly, the Nadanadaling Range became a typical plate subduction zone.Simultaneously the continental marginal area in the eastern part of Jilin and Heilongjiang provinces was activated, giving rise to faulted basins and strong eruptiveintrusive activities. As a result, a great Late Triassic volcano-granitic belt was formed. This area appeared to be an active continental margin of Andes type.