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4 METHODOLOGY 
Using the base map, by the visual interpretation of IRS-1C imagery, major structural features were interpreted. 
The lithological and structural details were identified and demarcated using aerial photographs (1:4,000 scale) 
and mirror stereoscope based on photogrammetric elements like tone, texture, pattern, shape etc. The different scales of 
interpretations were integrated and a map of 1:12,500 scale was produced. Field checks were carried out before final 
lithological and structural maps of the study area were prepared. 
5 RESULTS AND DISCUSSION 
The integrated maps (Fig.1) of the area exhibits the following major structures namely fold, lineaments, joints and 
lithological unit’s viz., magnetite quartzite, pyroxene granulite and gneisses were identified. 
5.1 Structure 
. The structural features like dip, strike, folds, joints, faults, lineaments were recognised by the visual interpretation and 
|. the details are given below (Table.2). ; ; mis but d ua 
  
  
CHARACTERS . Interpretation of . Interpretation . Field 
: Aerial photo .. of IRS-1C : Study 
1. Lithological Visible m Visible Iron bands 
units "o | mapped 
2. Attitude of Strike & Dip Trends Attitudes 
; . beds marked interpreted measured. 
3... Folds - Syncline . A Basin - Doubly 
d : Plunging 
| : Syncline 
4. Joints Numerous di Invisible | Horizontal, 
us . Vertical & 
E uv ; Inclined 
5. Lineaments Very Good - Fair .. Good 
  
Table. 2 Remote Sensing and field characteristics of magnetite quartzite iron bands. - 
511 Fold - 
In the study area, the major geological structure is fold and this had been recognised by many earlier workers (King : 
and Foote, 1864 ; Krishnan, 1921 ; Aiyengar, 1964; Saravanan, 1969). had described it as a plunging syncline on 
the basis of plunge towards east with amounts of 15° to 20°. The aerial photos interpretation helped in 
demarcating the different thickness and attitudes of bands of magnetite quartzites and basic granulites. It also, revealed 
the closure of beds along eastern and western margin: In field, the northern flank dips towards south from 52°to 57° 
and southern flank dip towards north with 45° to 47°. It is recognised as asymmetrical doubly plunging syncline. 
- 
5.1.2 Joints 
The fractures are in the form of joints observed in the rocks. These fractures were also interpreted through aerial 
photographs and satellite imageries. The banded magnetite quartzite exhibits large number of joints. These . 
rocks are broken along joints and are observed as boulders and blocks. There are three sets of joints observed viz. 
vertical, horizontal and oblique whose lengths varies from 15 cm to 3 mt. They trend in alldirections without 
 .any specific preference , which may be attributed to forces, provided by the intrusion of basic magma and granite . 
gneiss. The joints are observed only in the deformed zones suggesting deformation. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 1221