摘要：Remote sensing studies based on Landsat imageries and relief map followed by field studies have been carried out along the Kayathar-Tirunelveli-Valliyur transect of Achankovil suture zone. Five patterns of lineaments, two sets of conjugate shear system of dextral Tenmalai shear of D2 and sinistral Achankovil shear of D3 were delineated. F1 isoclinal rootless fold, E-W upright folds of F2 of D2; reorientation of F2 upright folds during D3 deformation, F3 doubly plunging fold due to interference of F2 and F3 folds were identified. The major isoclinal S type Vallanadu quartzite fold is a shear fold and its eatern limb displaced sinistrally for 11 km are highlighted from field and remote sensing studies. The F1, F2 and F3 co-axial folding suggest continued subduction of Madurai block sediments under Kerala Khondalite block through Achankovil suture zone during periods from D1-D2 deformations of Neoproterozoic to Cambrian time. F4 cross folding of F2 and F3 folds were formed during late D4 deformation.
