4. •Diastrophism – deformation
of the Earth’s crust.
• Folding – bending of solid rock
due
to compressional forces over
a
long period of time.
• Faulting – breaking of solid rock
12. •Recumbent fold has an
essentially horizontal
axial plane. linear, fold
axial plane oriented at
low angle resulting in
overturned strata in one
limb of the fold.
16. • Isoclinal folds are similar to
symmetrical folds, but these folds
both have the same angle and are
parallel to each other.
• 'Iso' means 'the same' (symmetrical),
and 'cline' means 'angle,' so this
name literally means 'same angle.’
• So isoclinal folds are both
symmetrical and aligned in a parallel
fashion.
22. FORCES THAT SHAPE THE
EARTH’S SURFACE
• There are three main types of forces of
pressure that work to shape (and re-shape)
the Earth’s surface:
–Compression forces (‘squeezing’)
–Extension (or tension) forces (‘stretching’)
–Shearing forces (‘ripping’)
24. NORMAL FAULTS: DIP SLIP
FAULTS
• Normal faults are the result of tensional (or
extensional) forces acting to pull apart the
surface.
• The hanging wall drops relative to the
footwall.
• Normal faults can occur across vast areas
due to lithospheric stretching.
– Basin and Range in Western USA
28. TRANSFORM FAULTS:
SHEARING FORCES
• Transform faults can be found at plate
boundaries as one plate slides horizontally
past another.
– Strike-slip faults
• Most transform faults are found on the
ocean floor as part of the active offset
along divergent plate boundaries.
29. TRANSFORM FAULTS: PLATE
BOUNDARIES
• At plate boundaries, when two tectonic
plates grind past each other, there is
usually no volcanism or mountain building
occurring.
• One of the largest transform faults in the
world is the San Andreas Fault
– Separating the North American Plate from the
Pacific Plate in southern California.
32. San Andreas Fault in the
Carrizo Plain
View is looking south. Fault
is in the center of the folded
ridge area
33. CONSEQUENCES OF SAN
ANDREAS FAULT
• Along the San Andreas Fault, the Pacific plate slowly
grinds to the north.
• Los Angeles lies on the Pacific plate side of the fault,
while San Francisco is on the North American side.
– About 25 million years in the future, if movement continues in the
same direction, Los Angeles will be a suburb of San Francisco
(or vice versa)
• The San Andreas is a right-lateral transform fault, which
means that if you imagine standing on either side of the
fault and looking across to the opposite side, it seems to
you that the people and objects on the opposite side are
moving to your right.
34.
35. •1. WHEN ROCKS BEND
DOWNWARD, THEY
FORM _______
•a. limbs
•b. syncline
•c. anticline
•d. cliff
38. •4. NORMAL FAULT IS
CAUSED BY
•a. tension
•b. compression
•c. expansion
•d. collision
39. •5. ROCKS UNDER
TENSIONAL FORCE ARE
•a. pushed towards each
other
•b. compressed
•c. expanded
•d. pulled apart
40. • 6. A FOLD MOUNTAIN IS A
TYPE OF LANDFORM THAT
IS CREATED WHEN TWO
CRUSTAL PLATES
• a. converge
• b. break
• c. diverge
• d. sink
41. •7. THERE ARE HOW
MANY TYPES OF FAULTS
•a. one
•b. two
•c. three
•d. four
42. • 8. CONVERSELY, A RIFT
VALLEY CAN BE FORMED
FROM A REVERSE FAULT
CAUSED BY
• a. tensional force
• b. compressional force
• c. expansion force
• d. contact force
43. •9. WHEN ROCKS BEND
UPWARD, THEY FORM
•a. monocline
•b. anticline
•c. syncline
•d. cliff
44. • 10. WHAT TYPE OF FORCE
IS INVOLVED IN THE
FORMATION OF
TRANSFORM FAULT?
• a. compressional force
• b. shearing force
• c. tensional force
• d. extension
