179 
Figure 13: 
Geologic Map of Bandung, at- 
1:100,000 scale (Silitonga, 1973). Letter synbols 
related to the synbols in the image interpretations. 
The image edge enhancement technique coirmonly 
involve three steps: a) the creation of low pass 
filter b) subtraction of the high frequency component 
from the original data, and c) addition of this high 
frequency component, which is the edge-component, back 
to the original data. These steps create a new image 
with increases in brightness and contrast of their 
edges. 
The Edge-Enhanced (EE) Band-7 imagery of the 
Sukabumi and Lenbang area show increases in contrast 
along the edges of their texture pattern groups. The 
EE Band-7 imagery from the Sukabumi area (Figure:14) 
shows the high relief of the Qr2 materials with a 
bright tone. Tuffaceous sandstone (Tpt) at the center 
of the imagery, characterized by its fold axes, 
lineaments and some bedding, is easily 
distinguishable. The north - south drainage system is 
shown shifted to SW, blocked by highly resistant 
volcanic breccias of Jampang block (Te6) (Figure:l5). 
These volcanic breccias form a topographic linear 
escarpment along the Cimandiri river. Hot springs 
were also found along the river. These two 
indications combined with previous indicators provide 
the researchers with confidence on the location of 
Cimandiri fault zone. 
The relation of the Cimandiri fault zone to the 
regional structural pattern was examined from 101 
lineaments drawn in this test area (Figure:lb) 
which showed distributions in three main sectors: E-W, 
NW-SE, and N-S. Conparing these lineament 
distributions with the distributions of faults, 
fractures and quartz veins (Figure:1?) and also 
considering the model of stress system with its fault 
types and extentional fracture (Fig:l8), showed a 
strong N-S maximum principal stress. It is also 
interpreted that the E-W lineaments are mostly formed 
by fold axes, thrust faults and fault scarps, and that 
the N-S lineaments are mostly related to strike-slip 
faults, fractures and quartz veins, while the NW-SE 
Figure I4fe Landsat Edge-Enhanced Band-7 imagery 
of Sukabumi area. Arrow indicates look direction 
to the Janpang volcanic breccias C№6) shown 
in Figure 15. 
Figure 15: Linear escarpment formed by Janpang 
volcanic breccias (Te6) shown in the background. 
lineaments are probably formed by fractures due to 
uplifts which formed as a result of the N-S maximum 
principal stress. A structural geologic map drawn 
from the Landsat Band-7 IEE imagery (Figure: 19) 
clearly shows the influence of the N-S stress 
responsible for the development of these structural 
features. 
The distributions of ridge axes, which may resemble 
fold axes, bedded layer, lithologic contrasts and 
fault scarps, found in the non-Quarternary volcanic 
materials on the Landsat Band-7 full-scene imagery of 
West Java (Fig:20) showed four groups of ridge axis 
direct ions. Analysis of the orientation of axis 
directions perpendicular to these ridge axes resulted 
in stress directions between N 2 0 E and N 16°E which 
agree with the regional maximum principal stress 
direction the West Java area previously determined. 
Landsat edge enhanced Band-7 imagery of the Lenbang 
area increases the sharpness of the fault scarp and 
the apparent offsets of some of the drainages. Using 
this enhanced image, together with the relief map de 
veloped from this enhanced image (Figure:21 &2fc), the 
trace of the fault can be followed extending to the