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蓟县地区长城系常州沟组沉积特征如下:底部河流相砂岩斜层理倾向玫瑰花图指示常州沟早期为近NE古流向,结合常州沟组底部的重矿物分析,反映早期河流相沉积的物源区为沉积区西南部五台古陆和密云—怀柔隆起区;常州沟组碎屑沉积物源主要来自克拉通源区,但再旋回造山隆升蚀源区也提供极少量物源。结合中元古时期区域内张性构造背景下侵入岩体资料证据,燕辽裂陷槽成因属克拉通内部裂解,即属陆内克拉通盆地,而不是裂谷型大陆边缘盆地。但研究区可能处于克拉通与大陆边缘造山带的毗邻地带,因而接受了极少量远距离搬运的再旋回造山隆升蚀源区碎屑。以常州沟组为视角,借助已有成果资料,简要探讨了燕辽裂陷槽演化史,燕辽裂陷槽的演化发展经历了大陆裂谷—坳拉槽阶段,并未过渡到洋盆阶段便克拉通化,是一发育不完全的裂谷。
The sedimentary features of the Changchenggou Formation in the Great Wall of Jixian are as follows: The obliquely oriented rose pattern in the bottom fluvial sandstone indicates that the Changzhou ditch was near NE-trending in the early period. Combined with the analysis of heavy minerals at the bottom of the Changzhou gully, the source of early river facies deposition The area is the Wutai ancient land and the Miyun-Huairou uplift in the southwestern part of the sedimentary area. The clastic sedimentary source in Changzhou Gouqu mainly comes from the craton source area, but the source of the remnant orogeny uplift also provides very few provenance. According to the evidence of intrusive rock mass data in the mid-Proterozoic region under extensional tectonic setting, the genesis of the Yanliao rift groove belongs to the intracontinental cratonic basin, rather than the rift-type continental margin basin. However, the study area may be adjacent to the craton and the margins of the continental margin, and thus received a very small amount of remolded orogeny remnants from long-distance source rocks. From the perspective of Changzhou Gouzhang, with the help of the existing data, the evolution history of the Yanliao rift was briefly discussed. The evolution of the Yanliao rift experienced the continental rift-to-aulan trough stage and did not transition to the ocean basin It is carat Tonghua, is a development of incomplete rift.