Abstract: Conjugate en-echelon vein arrays well-developed in the limestone of the Helvetic nappes of western Switzerland have been studied. They can be divided into two types: the primary and the surperimposed. The geometry of the veins and arrays have been described in detail. It may be concluded that the en-echelon veins discussed are synte-ctonic extension veins which were associated with the second order stress field due to the motion of the shear zone. The angle between the veins and array containing them and the conjugate angle between two shear zones have been measured. It is suggested that the former,varying from 20皌o 45?,depends on the normal stress acting on the shear zone. It is considered that the en-echelon veins were formed under the transitional condition from brittle fracture to ductile flow of the rocks. The generation of veins has been connected with the developmental history of the nappes.

摘要： 对瑞士赫尔文特推复体的灰岩中的共轭雁行脉列进行了研究。它们可被分成两大类:原生的和叠加的。对其几何形态的研究表明,小脉是同构造的,充填张裂而成的,它是由剪切带运动而派生的次级应力场所引起的。小脉与脉列的夹角一般变化在20°到45°左右,与作用在剪切带上的正应力大小有关。共轭雁行脉列的形成反映了岩石处于脆性到韧性的过渡的变形状态,与一定的形成深度有关。不同世代的脉反映了推复体形成和置位过程中的不同阶段。