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IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring", Hyderabad, India, 2002 
structure is observed in both NW-NE directions. In the case of 
NE direction, maximum number of faults is observed in N 35°- 
45? E, while in NW direction it is N 259-35? W. Some of these 
fractures are also observed in EW direction. 
In Kota formation, the general trend of all these features is 
slightly towards NNE direction. Maximum number of these 
features falls in N 57-15? E direction. In this case, only few of 
these structural features are observed in NW-EW directions. 
In Chikiala formation, it is observed that the major trend is 
towards NW direction with a maximum number falling in N 
25°-45° W. Some of these features are also observed in ENE 
and EW directions and very few in NS direction. 
7.6 DECCAN TRAP 
Two major trends are observed in NE and NW-SE while 
majority of them are lying in NE direction. In NE direction, 
the maximum number of these features is in N 45°-55° E 
direction. It completely absent in NS and EW directions. 
7.7 COASTAL GONDWANA FORMATION 
In Gollapalli sandstone, it is observed that the major trend of 
lineaments and faults is in NS and NNE directions, with a 
maximum number in NS direction. Very few are observed in 
NE-SE direction. 
In Raghavapuram shale, majority of these features are showing 
NW direction followed by ENE-WSW direction with a 
maximum number in N 45°-55° W. Lineaments and faults 
trending in NS and EW directions are conspicuously absent. 
In Tirupati sandstone, the general grain structure of the 
formation trends between NNW, WNW and ENE-NE 
directions. North-south and east-west trends are conspicuously 
absent (Figure-1). 
7.8 RAJAHMUNDRY SANDSTONE 
It is observed that these features are more or less equally 
distributed in both NW-NE directions in the same angle 45°- 
55°n either side. Lineaments and faults trending in NS and 
EW directions are completely absent. 
7.9 ALLUVIUM 
In this, majority of the features trend in N 65°-75° E. Minimum 
number of these features is observed in NW direction, while 
NS & EW directions they are almost nil. 
7.10 GONDWANA FORMATION 
Trends of all the three structural features namely, lineaments, 
faults, and shear zones of the Gondwana formation (Talchir, 
Barakar, Barren measure, Kamthi, Maleri, Kota, Chikiala, 
Gollapalli sandstones, Raghavapuram shales, Tirupati and 
Rajahmundry sandstones) are combined. From this, it is 
observed that the general structural grain of these formations 
appears to be in NW-SE, NE-SW followed by NNE directions. 
7.11 GODAVARI BASIN 
All structural features namely, lineaments, faults, and shear 
zones identified in all the lithological formations viz., 
Precambrian, Sullavai, Pakhal, Deccan trap, and upper and 
lower Gondwana formations of the mainland and coastal area of 
the Godavari basin are combined. From this, it is observed 
that the major trend of these formations is in NNW i.e., N 25°- 
35° W. In addition, NNE-NE trend is also seen prominently, 
while the fractures in EW direction are moderate. 
8. DISCUSSION 
Broadly, it is observed that the area consists of NW and NE 
trending fractures, which are nearly orthogonal to each other. A 
rose diagram plot of 10? interval of all the lineaments, indicates 
two preferred directions, i.e., NW-SE and NE-SW of which 
NW-SE trend is the most important direction (Ramanamurty 
and Parthasarathy, 1988). The major geological units of the 
Godavari valley in southeastern India constitute Archeans, 
Pakhal (middle Proterozoic), Lower Gondwana (Talchir, 
Barakar, Barren Measure and Kamthi) and Upper Gondwana 
(Kota, Maleri, and Chikiala). The Pranhita Godavari and the 
coastal Gondwana basins are controlled by pre-existing 
lineaments in Precambrian terrain, which are successors to the 
Pakhal and Sullavai basins. It is a major rift valley with an 
average width of 50km and the Pakhal, Sullavai, and Gondwana 
sedimentation took place in fault-controlled troughs trending 
NW-SE. The faulting probably continued pene- 
contemporaneously with deposition and only during early 
stages of Gondwana sedimentation, the sediments overflowed 
the main trough and are now preserved as isolated outliers 
beyond the main basin. A step-wise rift structure in the 
Pranhita-Godavari valley basin is inferred based on gravity data 
and it is envisaged that Pakhal, Sullavai, and Gondwana 
sediments were laid in successively developed block faulted 
trough. Three phases of faulting were occurred in this basin 
and are classified into three major types viz., 1) Boundary 
demarcating master fault or fault system, 2) The intrabasinal- 
intraformational faults, and 3) The basin-marginal faults. 
The faulting in the Godavari Valley was, by and large post- 
depositional and probably took place long after these beds were 
deposited (Ahmad and Ahmad, 1977). It is usually difficult to 
say when faulting was initiated in any area. Anderson (1951) 
states that “from the dynamical point of view it is the date of 
actual initiation of a fault which is important, as opposed to that 
of any subsequent movement along it, and former is in general 
extremely difficult to determine". Gondwana faulting is no 
exception to this rule. 
Varadarajan and Ganju (1989) stated that it is logical to infer 
that movement along the NE-SW direction is responsible for the 
generation of the step faults modifying the morphology of 
existing Godavari graben. Agarwal and Bansal (1983) brought 
out that the Pranhita-Godavari basin initially formed due to 
NW-SE trending Dharwarian trend appears to have been 
segmented into various blocks essentially by NE-SW trending 
faults. Based on remote sensing techniques the regional 
tectonic frame work of the Gondwana basin brings out three 
bulbous trough like continuous depositional basins where 
Pakhal, Sullavai, upper and lower Gondwana sediments have 
been deposited (Rao et.al, 1996). It is well known that in the 
Precambrian terrain particularly in the cratonic areas or shield 
areas, this type of trends generally occur and have been treated 
as a regmatic shear pattern, which may be the resultant 
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