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1-- Write
on 5 (Five) of the following:-
a-
Stress regime and
fault types
b-
Geometric
classification of joints
c-
Factors affecting
rock deformation.
Answer c: rock type, pressure, temperature, strain rate, time,
fluids
d-
Importance of
fracture orientation
e-
Types of joints
f-
Genetic
classification of joints
2-- True or false
a-- Normal
faults form in response to horizontal, tensional stresses that stretch or
elongate the rocks. ( True )
b-- Fractures
in rock that have not involved any fault slippage are called joints (True )
3- Which of the following locations
would be expected to exhibit normal faults?
A. the East African Rift Valley
B. the mid-Atlantic ridge
C. divergent plate boundaries
D. all of the above
E. none of the above
5-- Referring to the pictures above, give the
name of the fault responsible for the deformation in each of the four 3-D
cross-sections (A, B, C, and D). Then, specify the type of stress that
generated the fault.
A-
Right lateral strike slip
fault due to shear stress
B-
Left-lateral strike slip fault due to shear
stress
C-
Dip-slip normal fault,
tensional stress
D-
Dip-slip reverse fault, compressional stress
Good luck
Systematic
joints: have a
subparallel orientation and regular spacing.
n Joint set: joints that share a similar
orientation in the same area.
n Joint
system: 2 or
more joints sets in the same area
n Nonsystematic
joints: joints
that do not share a common orientation and those highly curved and irregular
fracture surfaces. They occur in most area but are not easily related to a recognizable stress.
Some times both systematic and
nonsystematic joints formed in the same area at the same time but
non-systematic joints usually terminate at systematic joints which indicates
that nonsystematic joints formed later.
d- Importance of Fracture Orientation
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Study of orientation of systematic
fractures provides information about the orientation of one or more principle
stress directions involved in the brittle.
Parameters measured for fractures are
strike and dip.
Or strike of linear features from
aerial photos and landsat images.
Data obtained from fractures is
plotted in rose diagram or equal area net. Equal area net for strike and dip
and rose diagram for strike only.
Studies of joint and fracture
orientation from LANDSAT and other satellite imagery and photographs have a
variety of structural, geomorphic, and engineering applications.
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