1 2
3 4
PR R
ICONSTRUCTION 5
6
7
Alternative lay out plan of a sub-sea road tunnel at planning 8
Alternative lay out plan of a hydropower scheme 9
10
1. Desk Study
11 Topographic maps
Geological maps, reports and literatures
Remote sensing (Air/Setalite Photos)
Data and information from previous near by Projects Data base from the Web
Upper Tamakosi Project Layout Plan, Nepal Project location
12
13
Available regional geological
maps are in general in scale of
1:250,000
Remote Sensing / Aerial Photos
14
1 km
Remote Sensing / Aerial Photos
Satellite image of Tsho Rolpa glacier lake 15
Interpretation of the
16
17 18
19 20
21
A. Joint rosette
Mapping of joints and discontinuities
22Pole contour plot for major joint sets
Stereographic projection
23 24
Sand Geophones
Impact
i Direct wave
Refracted wave
Increasing velocity with depth Clay
Rock P Wave
r
r = 90 degrees
25
Velocities of compressional (P) waives of some common rocks
26
(Bell, 2007)
Seismic reflection
Law of reflection
The angle of incidence (i) = angle of reflection
27
Z= Depth to source unit
T= Travel time from detector to geophone
V= Average velocity of travel
()
[]5.02
2
2
1
x
VT
Z?
×
=
Electrical resistivity
Electrical current is introduced
into the ground by means of two
current electrodes and the
potential difference is measured
Generally potential drop or
apperent resistance is directly
measured in Omhs
Omh value is converted to
apperent resistivity by use of a
factor
28
Typical resistivity value range for different ground material
30
Expensive method of investigation
Restricted to the most needy area of 31
32
33
An example format for core logging 34
35 36
37 38
39 40