loped 
gional 
id 
e 
200 
dry 
ny 
De 
etailed 
T 
ristics 
ay be 
1S 1 
| using 
to tank 
under 
)istance 
In addition to above major groups, yield capacities of wells have been studied according to different 
different rock types such as Charnockites, Granites, Granitic gneiss and Homblende biotite gneiss etc. 
Figures 3 and 4 show the yield capacities of tube wells related to the distance parameters in group 1 and 2. 
  
  
  
..... 
  
250 4. 
TOO 4 + 
- — 200 4 
600 E 
— 5904 = 
5 a 50 + 
= 4007 . = 
a > 
HE li 100 4 
^ 2004 
; 30 
1004 $ 4 
4 0.8 m ° * 
a PLE AM M I tn» > 
0 : t f I de Eo 0 
0 50 Ico 150 200 300 0 
DISTANCE m) 
Figure 3: Scatter diagram, distance to valley 
100 200 
DISTANCE (m) 
Figure 4: Scatter diagram, distance to lineament 
Further analysis of well yields with respect to different directions of lineament and valley groups were 
carried out in order to establish decision rules for well location studies. Tablel shows the decision rules 
obtained from the analysis, mentioned above, which will be useful for groundwater exploration strategies 
with emphasis on well location on localized requirements. 
  
  
  
  
  
  
  
  
  
  
Spatial feature Spatial feature Decision rules (for well 
location) 
Lineament Distance to lineament and Favorable distance from the 
lineament-direction lineament = 0 - 90m 
Favourable direction = 60°-120° 
and 120°-150° 
Valley Distance to valley and Valley Favorable distance = 0 - 100m 
direction Favorable direction = 30° W-30°E 
Tank Distance to upstream and Distance to upstream = 0 - 150m 
downstream of the tank Distance to downstream = 0 - 800m 
Interflues Distance to drainage divide distance to drainage divide >200m 
Drainage Sream order 3" and 4" order are more 
favorable 
Table 1. 
361 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B7. Vienna 1996