Rajendram, S. 
  
- 5.1.3 Faults 
The fault zones that were identified through remote sensing were meager and are distributed on the eastern and 
western margin of Kanjamalai trending in NNE-SSW directions. These run for 20-35 mts and brought slight 
displacement of magnetite quartzites bands without much deformation. Thus, these are considered as a minor 
structural feature. 
5.2 Lineaments 
The next structurally controlled features are the lineaments that are clearly interpreted on both imagery and aerial 
photographs. This category includes all structural alignments, topographic alignments, vegetation linear, shapes 
and lithological boundaries and contacts between physiographic units. These appear to reflect the geology and 
are of surface expression of buried structure. The study area has lineaments trending in NNW-SSE, E-W, and 
NE-SW directions. Based upon the lineament concentration, three groups of major lineaments were identified viz., 
Group 1. Lineaments of Tirumanimuttar river 
A major lineament trending NNE-SSW running to a length of 8 km had been observed! It runs parallel to 
Tirumanimuttar river representing a weak zone. It is located close to the ‚deep main fault zones near Salem (Grady, 
1971). 
Group 2. Lineaments of Gneissic area 
These are. distributed at different direction and at various places. Further, the lineaments in this area are small and 
short ending] in NNE-SSW, NE-SW and NNW-S SE directions. 
Group 3. Lineaments of Kanjamalai area 
It “includes lineaments that are in and around Karnal which are small and trending NNE-SSW and NE-SW : 
directions. They pass through the area from where minor streams drains from the hill top. A major lineament was 
identified which cuts across the Kanjamalai hill and is trending in E-W direction. This lineament is parallel 
to Godumalai shear zone , which is an extension of Attur Fault Zone in Salem. The development of these lineaments 
is attributed towards the forces that had developed the folds or later deformation of Kanjamalai hill. 
. 5.3 Lithology 
In the area, the magnetite quartzite is associated with pyroxene granultie and granitic gneiss and shows sharp contact. 
The iron ore exhibits dark grey tone, medium to coarse texture with linear banding and are easily differentiated from | 
the other rock types (Table.1). In field, their contacts with other rock types are difficult on account of highly 
fractured and broken down pieces of ores in the form of float ores / debris. at the foot hill. The intermixing of 
granulites and magnetite quartzite is absent. The minerals of granulites exhibit parallelism with magnetite 
quartzite. At some places, the contact zone is covered by weathered zone. It also shows sharp contact with the 
gneisses ofthe study area and exhibits parallelism to the banding of gneissic contact and there is no indication of 
intermixing. : 
6 CONCLUSION - 
The utilisations of aerial photograph and satellite imagery have proved fruitful for the present study. Aerial photos 
have provided details , which have its own relation with relief and because of stereoscopic vision and higher 
resolution the lithology and structure were identified. Visual interpretation of IRS-1C data was much beneficial for 
geological and structural studies as it has provided synoptic view of large area at a time. The interpretations 
suggest that the Kanjamalai represents asymmetrical plunging synclinal hill and the major lithological types are . 
magnetite quartzite iron ore formations, granulites and gneisses. 
  
1222 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.