闽赣交界武夷山南段“桃溪穹隆”形变特征及构造演化探讨

Deformation characteristics and tectonic evolution of the Taoxi dome in southern Wuyishan on the boundary of Fujian and Jiangxi Provinces

"桃溪穹隆"由内核、中间层和盖层组成,发育岩石流变,韧性、韧脆性和脆性变形(断裂)。文章以"桃溪穹隆"内核、中间层和盖层为对象,通过研究其形变特征、运动形式及相互关系,探讨穹隆上隆的运动方式,结合沉积事件、岩浆活动和构造运动,阐述穹隆的形成机制和构造演化特征。"桃溪穹隆"于加里东期(志留纪末)隆升,华力西期—印支期(晚二叠世—中三叠世)大规模上隆,燕山期及后期继承性活动,主隆升期(华力西期—印支期)为逆时针旋转上隆。穹隆长期隆升是该区古元古代结晶基底出露的主要原因。

The Taoxi dome is composed of inner core, intermediate layer and cap rock, each of which developed various structural deformations, including theologic, ductile, ductile brittle and brittle deforma tion （fracture）. With the tectonic deformations of each structure as the research targets, this paper dis cussed the uplift process of the dome through analyzing deformation characteristics, movement modes and their relationships. The forming mechanism and tectonic evolution of the dome were expounded based on the depositional events, magmatism and tectonic movement. Out study shows that the Taoxi dome started to uplift at the Caledonian period （end of Silurian） and ascended in a large scale during the period from the Variscan （Late Permian） to the Indosinian （Middle Triassic）, followed by inherited activities in the Yans hanian and later, with anti clockwise rotation uplift in the main uplift period （Variscan Indosinian）. The long term uplift of the dome may be the leading reason for exposure of the Paleoproterozoic crystalline basement in the study area