Abstract: Deformation partitioning occurring in ductile sheac zones gives rise to the growth of noorotated porphyroblasts within the zoae dominated by coaxial or non-coaxial progressivc shortening during progressive deformation.Accordiagly,the iaclusion trails withia the porphyroblasts represent tbe remnant structures and textures of previous deformation and metamorphjsm preserved ia the porphyroblasts.Thus,detailed observation and studies of tbe inclusion trails in the noa-rotated porphyroblasts help to define tbe oricntation of early foliation,uncover the temporal indicator of.tectonic evolution and determine the correlationship between deformation and metamorphism and tbeir evolution history to a more realistic situation.Inclusion trails,within the porphyroblasts such as garaet and biotite ia the large scale Tuole Pasture strike-slip ductile shear zone,North Qilian orogenic belt,suggest that the porphyroblasts did not rotate during ductile deformation,therefore,silimoid inclusion trails and multi-stages of foliation formcd as a result of deformation partitioning and replacement of fbliation in response to progressive deformation.Though with certain extent of delay,progressive deformatioo is concurreat with pro-grade metamorphism in large.The zone undergone most cxtcnsive deformation and metarnorphism is usually referred to be located in the centre of ductile shear zone,but in this ductile shear zone,the most intensive metamorphism and deformation occurred just next to the central part,which is demonstrated by the varia- tion of structure pattern of folding from type B,via type AB to type A,the transitioa of characterized mineral assemMages from Gt +Bi→ Gt+Bi→ Sta→ Gt+Bi+Ky+Chd→Gt+Bi,and thc variation Of grain size Of prophyroblast from small→ larger→largest→fine (but with high conteat) from rim to centre of the ductile shear zone.Fluid process involving in the shearing may have certain effect on strain rate,for example the intecgranular water will facilitate the shcaring and increase tbe strain rate.Under the pro-grade metamorphism,dehydration reactioos would release a nurnber of watcr giving rise to the increasiag of intergranular water,which would enhance the ductile shearing.while metamorphism had rcachcd to the.peak metatrnorphism,hydration reactions would lead to the reduction of iotergraaular water,thererore,the straln rate would greatly decrease.It is showm that there is important relationship between folded cleavage and porphyrobast growth.The geometry and structure patterns of the inclusion trails developed within the porphyroblast do help to reveal the variations of strain rate,unt ravel tectonic evolution history and determine the relation between deformation and metamorphism during ductile shearing.