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Regional mapping of a section across the Eastern Ghats Mobile Belt (EGMB) north of the Godavari graben in Eastern Peninsular India by using Landsat Thematic Mapper data enables recognition of a number of shear zones, lineaments, and structural domes and basins. A conspicuous megashear occurs at the western boundary of the granulite faaes rocks of the EGMB adjacent to the Archean granitegreenstone craton. The confinement of a suite of alkaline igneous rocks to this shear zone is a notable feature. The strike extensions of this shear belt extend through to the Elchuru alkaline complex, Prakasam District, Andhra Pradesh, and the syenite plutons of Koraput district, Orissa. The contrasting lithologies, metamorphism and structural history on either side of the shear zone suggests that it might be a Precambrian suture zone.The mesoscopic structural features in the EGMB include prominent foliation with moderate to steep dips, folds, faults/shears, S-C fabrics, pinch and swell structures and other linear fabric elements. These observations favour the consideration of drastic crustal shortening and thickening and a complex deformational sequence. The major r,ock units in this part of EGMB comprise garnetiferous sillimanite g n e i s s , quartzites and calc-granulites forming the khondalitic suite of rocks and a wide variety of charnockitic rocks. The contact of the two rock units is generally sheared and often migmatised. essentially horizontal tectonic regime resulting in thrust systems and associated structures, subsequently followtd by strikeslip tectonics characterized by high shear strains. Features such as westward-verging thrusts, largescale recumbent folds, major shear zones, structural domes and basins, indications of tectonic crustal shortening, extensive calc-alkali magmatism and widespread rnigmatization in the region are attributed to collisional processes during Proterozoic times. The spatial disposition of the EGMB and its linkage with the distribution of similar rock units during the late Precambrian time in a global tectonic scenario are discussed.The structural fabric suggests two major tectonic events: an Terra Nova, 6, 72-81, 1994.

A method is developed for determining molecular conformations through analysis of experimental molar Cotton-Mouton constants in conjunction with known anisotropic magnetic susceptibilities and electric polarizabilities for structural groups. Molar Cotton-Mouton constants ( x 1OI6 e.m.u.), and derived interplanar angles, for molecules as solutes in carbon tetrachloride at 20°C are : biphenyl (+ 70, 0") ; 2,2'-bipyridyl (+ 76, 25") ; 9,9'-bianthryl (+ 160, 62") ; 9-phenylanthracene (+ 157, 70") ; 1-phenylnaphthalene (+ 79, 66") ; 1,3,5-triphenylbenzene (+ 169, 35").

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