Prognosis and mitigation strategy for major landslide-prone areas Varunavat Parvat landslide in Uttarkashi

DPM
17,5
630
Figure 3.
Structural map of
Varunavat Parvat and
surrounding area of
Uttarkashi township
lineaments) in the area. Most conspicuous structural discontinuity observed in the area
is anticlinal axis and fault along Bhagirathi river referred to as Baragadi anticline and
fault by Agarwal and Kumar (1973) and Indravati Bhagirathi fault by NRSA (2004). In
the area under investigation the NW-SE trend of this discontinuity is traced along
Indravati river from Ladari village upto further SE of Boga village. It is at Uttarkashi
that the trend of this anticlinal axis and fault changes from NW-SE to E-W and this
E-W trend is noticed along Badethi, Chamkot and Matli area and thereafter it extends
in northwest direction. Bhagirathi river between Uttarkashi and Matli and in the
further west follows this discontinuity and the broad river valley of Bhagirathi and its
meandering channel at Uttarkashi and downstream and severe bank erosion by
Indravati River and its broad valley indicate strong tectonic control that Baragadi
anticline and fault exhibits over the river courses of Bhagirathi and Indravati at
Uttarkashi and surrounding area (Figure 3). Another geomorphic expression of this
discontinuity is the sudden change in the upstream NE-SW trend of Bhagirathi river at
Uttarkashi, as it flows NE-SW in the upstream of its confluence with Indravati river
and in the immediate downstream of the confluence Bhagirathi river follows an E-W
trend. Another E-W trending structural feature in the area is synclinal axis of Sangrali
- Khand syncline (Figure 3) also referred to as Kot syncline by Agarwal and Kumar
(1973). NE-SW trending Pata-Sangrali fault intersects the axis of Kot syncline in the
west of Sangrali. The slow flowage around Sangrali and Pata villages and escarpment
in that area can be attributed to this discontinuity. NW-SE trending Kharuwan-Badethi
anticlinal axis and fault is another major structural discontinuity in the area and can be
traced from NW of Kharuwan to the SE of Wasunga village and extends further SE of
Badethi. The NW-SE disposition of Wasunga-Badethi Fan in this area and