![Page 1: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/1.jpg)
© 2006 Pearson Prentice Hall
This work is protected by United States copyright laws and is provided solely for
the use of instructors in teaching their courses and assessing student learning.
Dissemination or sale of any part of this work (including on the World Wide Web)
will destroy the integrity of the work and is not permitted. The work and materials
from it should never be made available to students except by instructors using
the accompanying text in their classes. All recipients of this work are expected to
abide by these restrictions and to honor the intended pedagogical purposes and
the needs of other instructors who rely on these materials.
Lecture Outlines
PowerPoint
Chapter 10
Earth Science 11e
Tarbuck/Lutgens
![Page 2: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/2.jpg)
Earth Science, 11e
Mountain Building
Chapter 10
![Page 3: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/3.jpg)
Deformation
Deformation is a general term that refers to all changes in the original form and/or size of a rock body
Most crustal deformation occurs along plate margins
Factors that influence the strength of a rock
• Temperature and confining pressure
• Rock type
• Time
![Page 4: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/4.jpg)
Folds
Rocks bent into a series of waves
Most folds result from compressional forces
which shorten and thicken the crust
Types of folds
• Anticline – upfolded, or arched, rock layers
• Syncline – downfolded rock layers
![Page 5: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/5.jpg)
Folds
Types of folds
• Anticlines and synclines can be
• Symmetrical - limbs are mirror images
• Asymmetrical - limbs are not mirror images
• Overturned - one limb is tilted beyond the vertical
• Where folds die out they are said to be plunging
![Page 6: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/6.jpg)
A series of anticlines
and synclines
Figure 10.3
![Page 7: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/7.jpg)
Plunging folds
Figure 10.5 A
![Page 8: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/8.jpg)
Outcrop patterns of
plunging folds
Figure 10.5 A
![Page 9: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/9.jpg)
Folds
Types of folds
• Other types of folds
• Dome
• Circular, or slightly elongated
• Upwarped displacement of rocks
• Oldest rocks in core
• Basin
• Circular, or slightly elongated
• Downwarped displacement of rocks
• Youngest rocks in core
![Page 10: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/10.jpg)
The Black
Hills of South
Dakota are a
large domeFigure 10.8
![Page 11: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/11.jpg)
The bedrock geology of
the Michigan Basin
Figure 10.9
![Page 12: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/12.jpg)
Faults
Faults are fractures (breaks) in rocks along
which appreciable displacement has taken
place
Types of faults
• Dip-slip fault
• Movement along the inclination (dip) of fault plane
• Parts of a dip-slip fault
• Hanging wall – the rock above the fault surface
• Footwall – the rock below the fault surface
![Page 13: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/13.jpg)
Concept of hanging wall and
footwall along a fault
![Page 14: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/14.jpg)
Faults
Types of faults
• Dip-slip fault
• Types of dip-slip faults
• Normal fault
• Hanging wall block moves down
• Associated with fault-block mountains
• Prevalent at spreading centers
• Caused by tensional forces
![Page 15: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/15.jpg)
A normal fault
Figure 10.12 A
![Page 16: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/16.jpg)
Fault block mountains produced
by normal faulting
Figure 10.13
![Page 17: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/17.jpg)
Faults
Types of faults
• Dip-slip fault
• Types of dip-slip faults
• Reverse and thrust faults
• Hanging wall block moves up
• Caused by strong compressional stresses
• Reverse fault - dips greater than 45º
• Thrust fault - dips less than 45º
![Page 18: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/18.jpg)
A reverse fault
Figure 10.12 B
![Page 19: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/19.jpg)
A thrust fault
Figure 10.12 C
![Page 20: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/20.jpg)
Faults
Types of faults
• Strike-slip faults
• Dominant displacement is horizontal and parallel to
the trend, or strike
• Transform fault
• Large strike-slip fault that cuts through the
lithosphere
• Often associated with plate boundaries
![Page 21: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/21.jpg)
A strike-slip fault
Figure 10.12 D
![Page 22: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/22.jpg)
Faults
Types of faults
• Joints
• Fractures along which no appreciable displacement
has occurred
• Most are formed when rocks in the outer-most crust
are deformed
![Page 23: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/23.jpg)
Mountain belts
Orogenesis refers to processes that
collectively produce a mountain belt
Mountain building at convergent boundaries
• Most mountain building occurs at convergent
plate boundaries
![Page 24: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/24.jpg)
Mountain belts
Mountain building at convergent boundaries
• Andean-type mountain building
• Oceanic-continental crust convergence
• e.g. Andes Mountains
• Types related to the overriding plate
• Passive margins
• Prior to the formation of a subduction zone
• e.g. East Coast of North America
![Page 25: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/25.jpg)
Mountain belts
Mountain building at convergent boundaries
• Andean-type mountain building
• Types related to the overriding plate
• Active continental margins
• Subduction zone forms
• Deformation process begins
• Continental volcanic arc forms
• Accretionary wedge forms
• Examples of inactive Andean-type orogenic belts include Sierra Nevada Range and California's Coast Ranges
![Page 26: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/26.jpg)
Orogenesis along an Andean-
type subduction zone
Figure 10.18 A
![Page 27: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/27.jpg)
Orogenesis along an Andean-
type subduction zone
Figure 10.18 B
![Page 28: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/28.jpg)
Orogenesis along an Andean-
type subduction zone
Figure 10.18 C
![Page 29: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/29.jpg)
Mountain belts
Mountain building at convergent boundaries
• Continental collisions
• Where two plates with continental crust converge
• e.g., India and Eurasian plate collision
• Himalayan Mountains and the Tibetan Plateau
![Page 30: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/30.jpg)
Formation of the Himalayas
Figure 10.22
![Page 31: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/31.jpg)
Mountain belts
Mountain building at convergent boundaries
• Continental accretion
• Third mechanism of mountain building
• Small crustal fragments collide with and accrete to
continental margins
• Accreted crustal blocks are called terranes
• Occurred along the Pacific Coast
![Page 32: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/32.jpg)
Distribution of modern day
oceanic plateaus and other
submerged crustal fragments
Figure 10.19
![Page 33: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/33.jpg)
Accreted
terranes along
the western
margin of
North America
Figure 10.21
![Page 34: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/34.jpg)
Mountain belts
Buoyancy and the principle of isostasy
• Evidence for crustal uplift includes wave-cut platforms high above sea level
• Reasons for crustal uplift
• Not so easy to determine
• Isostasy
• Concept of a floating crust in gravitational balance
• When weight is removed from the crust, crustal uplifting occurs
• Process is called isostatic adjustment
![Page 35: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/35.jpg)
The principle of isostasy
Figure 10.27
![Page 36: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/36.jpg)
Erosion and resulting isostatic
adjustment of the crust
Figure 10.28 A
![Page 37: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/37.jpg)
Erosion and resulting isostatic
adjustment of the crust
Figure 10.28 B
![Page 38: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/38.jpg)
Erosion and resulting isostatic
adjustment of the crust
Figure 10.28 C
![Page 39: Lecture Outlines PowerPoint Chapter 10 Tarbuck/Lutgens...•Isostasy •Concept of a floating crust in gravitational balance •When weight is removed from the crust, crustal uplifting](https://reader030.vdocuments.us/reader030/viewer/2022040720/5e2bd4cd90a405225a331fdc/html5/thumbnails/39.jpg)
End of Chapter 10