1. DIASTROPHISDIASTROPHIS
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2. What is Diastrophism?What is Diastrophism?
 It is the dynamical forces generally tendIt is the dynamical forces generally tend
to elevate the earth’s surface.to elevate the earth’s surface.
 They are in constant battle againstThey are in constant battle against
external forces that tend to wear awayexternal forces that tend to wear away
the land surface.the land surface.

3. TYPES of EARTHTYPES of EARTH
MOVEMENTMOVEMENT
 UPLIFTUPLIFT
 Is the movement of the earthIs the movement of the earth
wherein the crust rises.wherein the crust rises.
 SUBSIDENCESUBSIDENCE
 A sinking or setting of a part ofA sinking or setting of a part of
the earth’s crust with respect tothe earth’s crust with respect to
the surrounding parts.the surrounding parts.
 THRUSTTHRUST
 Horizontal movement of theHorizontal movement of the
earth’s crust.earth’s crust.

4. THEORIES ofTHEORIES of
DIASTROPHISDIASTROPHIS
MM
 Theories of IsostasyTheories of Isostasy
 From the greek word meaning “equalFrom the greek word meaning “equal
standing”standing”
 States that as rock from higher region isStates that as rock from higher region is
removed by erosion and deposited on aremoved by erosion and deposited on a
lower region, the higher region slowlylower region, the higher region slowly
rises while the lower region becomesrises while the lower region becomes
heavier and slowly sinks.heavier and slowly sinks.

5. ContractionContraction
TheoryTheory
States that the earth is graduallyStates that the earth is gradually
shrinking.shrinking.
As the shrinkage occurs, theAs the shrinkage occurs, the
stronger and heavier blocks ofstronger and heavier blocks of
the crust sink while the weakerthe crust sink while the weaker
strata are crowded andstrata are crowded and
squeezed upwardsqueezed upward..

6. CONVECTIONCONVECTION
THEORYTHEORY
Is a theory which would account forIs a theory which would account for
the pushing and folding of rocksthe pushing and folding of rocks
through convection currents.through convection currents.
This process is true when it occursThis process is true when it occurs
under a continental mass.under a continental mass.

7. STRUCTURAL FEATURESSTRUCTURAL FEATURES
OF EARTH MOVEMENTOF EARTH MOVEMENT
 Deformation of rocksDeformation of rocks
The effects of diastrophism isThe effects of diastrophism is
more clearly seen in rocks,more clearly seen in rocks,
especially in sedimentary rocks.especially in sedimentary rocks.
Any deformation of sedimentaryAny deformation of sedimentary
rocks is shown in tilt, bends, orrocks is shown in tilt, bends, or
break in layer.break in layer.

8.  FOLDSFOLDS
A bend or flexure in a rock can beA bend or flexure in a rock can be
likened to waves on the ocean.likened to waves on the ocean.
Each has a crust or upfold and aEach has a crust or upfold and a
trough or downfold.trough or downfold.
 ““ANTICLINE”ANTICLINE”
 The crust of a rockThe crust of a rock
 ““SYNCLINE”SYNCLINE”
 The trough of the rockThe trough of the rock

9. DIP and STRIKEDIP and STRIKE
DIPDIP
The angle between theThe angle between the
horizontal plane and a structuralhorizontal plane and a structural
surfacesurface
STRIKESTRIKE
The direction of a line along theThe direction of a line along the
edge of an inclined bed where itedge of an inclined bed where it
meets the horizontal plane,meets the horizontal plane,
Always at the right of the dip.Always at the right of the dip.

10.  Pitching FoldPitching Fold
 Folds whose axes slant downward at eachFolds whose axes slant downward at each
end of an imaginary line running alone theend of an imaginary line running alone the
top of an anticline or along the bottom of atop of an anticline or along the bottom of a
syncline called “AXES of the fold”.syncline called “AXES of the fold”.
 ““PITCH”PITCH”
 The angel between the axis and theThe angel between the axis and the
horizontal.horizontal.

11. JOINTS and FISSURESJOINTS and FISSURES
 JOINTSJOINTS
 Is a fracture or a little separationIs a fracture or a little separation
between the rock wallsbetween the rock walls
 FISSURESFISSURES
 Cracks or actual gaps between theCracks or actual gaps between the
rock walls.rock walls.

12.  FAULTINGFAULTING
 It refers to the surface alongIt refers to the surface along
which a rock body has beenwhich a rock body has been
broken and has beenbroken and has been
displaced.displaced.

13. 2 TYPES OF FAULTING2 TYPES OF FAULTING
1.1. VERTICAL FAULTINGVERTICAL FAULTING
 Occurs when an entire block of rock is raisedOccurs when an entire block of rock is raised
evenly so that the layers remain in theirevenly so that the layers remain in their
original horizontal position.original horizontal position.
1.1. HORIZONTAL FAULTINGHORIZONTAL FAULTING
 OCCURS WHEN AN ENTIRE BLOCK OFOCCURS WHEN AN ENTIRE BLOCK OF
ROCK IS LOWERED EVENLY SO THATROCK IS LOWERED EVENLY SO THAT
LAYERS REMAIN IN THEIR ORIGINALLAYERS REMAIN IN THEIR ORIGINAL
VERTICAL POSITION.VERTICAL POSITION.