关键词: 陆相层序, 山间盆地, 事件层序, 侏罗系, 北京延庆

Abstract:

The study of continental sequence stratigraphy inherits achievements from marine sequence strata. While continental sequence stratigraphy which has more complex controlling factors develops different scales, system tracts characteristics compared to the marine sequence. These factors include tectonic movement, climatic change, volcanic events and so on. It is difficult to observe an integral sequence section in a local area obviously. In this paper, three typical continental sequence were found and researched detailedly of “flowerpot” basin located in “fossil wood” geological park within four square kilometers by outcrop surveying, sampling and natural gamma ray measurement. The first kind sequence is “normal sequence” which is affected by climatic and tectonic factors. The second kind is “event sequence” which is mainly affected by volcanic events. The last kind is “transitional sequence” which is intensively impacted by both mentioned factors. The type and identifying signature of several system tracts were also discussed. The widespread fossil woods in this area were considered as a result of lakeflooding. Its appearance was also considered as an index of flooding. All research findings interpreted typical sequence stratigraphy characteristics of minitype continental basin which was impacted by tectonic movement, climatic change and volcanic events.

Key words:  continental sequence, intermountainous basin, event sequence, Jurassic system, Yanqing County of Beijing