Prof. Anthony B. Watts

Contents

Preface
Acknowledgments
Notation

1. Historical Development of the Concept of Isostasy

1.1 Introduction
1.2 First isostatic ideas
1.3 The deflection of the vertical in India
1.4 Isostasy according to Airy
1.5 Isostasy according to Pratt
1.6 Fisher and Dutton on isostasy
1.7 The figure of the Earth and isostasy
1.8 Bowie's illustration of isostasy
1.9 The Earth's gravity and tests of isostasy
1.10 Isostasy and geological thought
1.11 Nature's great isostatic experiment
1.12 Success of the Airy and Pratt models of isostasy in explaining crustal structure
1.13 Bloom's test of isostasy
1.14 Summary

2. Isostasy and Flexure of the Lithosphere

2.1 Introduction
2.2 Gilbert and the strength of the Earth's crust
2.3 Isostasy according to Barrell
2.4 Bowie' criticism of Barrell
2.5 Putnam and local vs. regional compensation
2.6 Vening Meinesz and the radius of regionality
2.7 Gunn and the principle of isobary
2.8 Isostasy and plate tectonics
2.9 Walcott and flexure of the lithosphere
2.10 Summary

3. Theory of Elastic Plates

3.1 Introduction
3.2 Linear elasticity
3.3 Cylindrical bending
3.4 Flexure of beams
3.4.1 Stresses
3.4.2 Shearing force and bending moment
3.4.3 Winkler foundation 3.5 Beams of unlimited length
3.5.1 Infinite beams
3.5.2 Semi-infinite beams 3.6 Hetenyi's coefficients
3.7 Beams of variable rigidity and restoring force
3.7.1 Continuous variation
3.7.2 Circular plates 3.8 Summary

4. Geological Examples of the Flexure Model of Isostasy

4.1 Introduction
4.2 Glacio-isostatic rebound
4.2.1 Late-glacial shorelines
4.2.2 The Holocene sea-level problem 4.3 Seamounts and oceanic islands
4.4 River deltas
4.5 Deep-sea trench and outer-rise systems
4.6 Summary

5. Isostatic Response Functions

5.1 Introduction
5.2 The lithosphere as a filter
5.3 The gravitational admittance
5.3.1 Uncompensated topography
5.3.2 Airy model
5.3.3 Pratt model
5.3.4 Elastic plate (flexure) model
5.3.5 "Buried" loads 5.4 High-order terms
5.5 Isostatic response functions
5.6 Estimating admittance, coherence, and response functions from observations
5.6.1 Oceans
5.6.2 Continents 5.7 Summary

6. Isostasy and the Physical Nature of the Lithosphere

6.1 Introduction
6.2 The behaviour of Earth materials
6.3 Flexure of a viscoelastic plate
6.4 Relationship of elastic parameters to load and plate age
6.4.1 Oceans
6.4.2 Continents 6.5 Rheology of the lithosphere
6.5.1 Brittle
6.5.2 Ductile 6.6 The Yield Strength Envelope
6.7 Time-dependant flexure
6.8 Relationship between elastic thickness, curvature and yielding
6.9 Elastic thickness and earthquakes
6.10 Summary

7. Isostasy and the Origin of Geological Features in the Continents and Oceans

7.1 Introduction
7.2 Extensional tectonics and rifting
7.2.1 Continental rifts
7.2.1.1 Bullard's hypothesis
7.2.1.2 Vening Meinesz's hypothesis 7.2.2 Oceanic rifts
7.2.3 Rift-type basins
7.2.3.1 "Backstripping"
7.2.3.2 McKenzie's model of crustal and mantle extension
7.2.3.3 The crustal structure produced by rifting
7.2.3.4 Elastic thickness and the strength of extended continental lithosphere 7.2.4 Magmatic underplating
7.2.5 The post-rift stratigraphy of rift basins
7.2.6 Rift flank uplifts and erosional unloading 7.3 Compressional tectonics and orogeny
7.3.1 Crustal thickening
7.3.1.1 Shortening
7.3.1.2 Rheology 7.3.2 Orogenic belts and erosion
7.3.3 Foreland basins 7.4 Strike-slip tectonics 7.4.1 Transform faults
7.4.2 Fracture Zones
7.4.3 Transform margins
7.4.4 Strike-slip faults 7.5 Intra-plate deformation
7.5.1 Intra-cratonic basins
7.5.2 Intra-plate volcanism, mid-plate swells and hot-spots 7.6 Summary

8. Isostasy and the Terrestrial Planets

8.1 Introduction
8.2 Moon
8.3 Mercury
8.4 Mars
8.5 Venus
8.6 Earth - postscript
8.7 Summary Bibliography
Index

Electronic book

The electronic book consists of 14 Mathcad® files which illustrate various aspects of the computation of flexure due to 2-D and 3-D loads of arbitrary shape. The files can be read using Mathcad 7® or higher (i.e. Mathcad 8, Mathcad 2000).

Click here for a contents page.

Users of the world-wide will be able to download the files by