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CHAPTER V

PAGS

Land-forms In Regions Of Highly Folded And Dis-

Turbed Strata 92

Typical Rock-structures in Regions of Mountain-uplift—General

Structure of Mountains of Upheaval—Primeval Coincidence of Ln-

derground Structure and External Configuration—Relatively weak

and strong Structures—Stages in the Erosion of a Mountain-chain—
Forms assumed under Denudation—Ultimate face of Mountain-chains.

CHAPTER VI

Lank-forms In Regions Of Highly Folded And Dis-

Turbed Strata (continued) '28

Structure and Configuration of Plateaux of Erosion—Forms as-

sumed under Denudation—Mountains of Circumdenudation—His-

tory of certain Plateaux of Erosion—Southern Uplands and Northern

Highland* of Scotland—Stages in Erosion of Table-lands.

CHAPTER VII

Land-forms In Rkgions Affected By Normal Faults

Or Vi.ktk.ai. Displacements . . . . • 15°

Normal Faults, general features of—Their connection with Folds

—Their origin—How they affect the Surface—Faultsof the Colorado

region, and of the Great Hasin—Depression of the Dead Sea and the

Jordan Lake Depressions of East Africa—Faults of British Coal-

fields -Hounding faults of Scottish Highlands and Lowlands—Fault-
lioimded Mountains—(iencral conclusions.

CHAPTER VIII

Land-forms Due Directly Or Indirectly To Igneous

Action 173

Plutonic and Volcanic Rocks—Deformation of Surface caused by

Intrusions-Laccoliths of Henry Mountains—Volcanoes, Structure

and Form of—Mud-cones — Geysers—Fissure-eruptions — Volcanic
Plateaux—Denudation of Volcanoes, etc., and resulting features.

CHAPTER IX

Influence Of Rock Character In The Determina-

Tion Of Land-forms 195

Joints in Rocks and the part they play in determining Surface-

features— Texture and Minernlogicnl composition of Rocks in rela-

tion to Weathering—Forms assumed by various Rocks.

CHAPTER X

PACK

Land-forms Modified By Glacial Action . . 212

Geological action of existing Glaciers—Evidence of Erosion—

Origin of the Ground-moraine: its independence of Surface-moraines

—Infraglacial smoothing and polishing, crushing, shattering and

plucking—Geological action of Prehistoric Glaciers—General evi-

dence supplied by Ancient Glaciers of the Alps.

CHAPTER XI

Land-forms Modified By Glacial Action (continued} . 232

Former Glacial conditions of Northern Europe—Extent of the old

Inland Ice—Glacial character of Boulder-clay—Central Region of

Glacial Erosion and Peripheral Area of Glacial Accumulation—Fluvio-

glacial deposits—Loess, origin of its materials—Glaciation of North

America—Modifications of Surface produced by Glacial Action.

CHAPTER XII

Land-forms Modified By ^olian Action . . . 250

Insolation and Deflation in the Sahara—Forms assumed by Gran-

itoid Rocks and Horizontal and Inclined Strata—Reduction of Land-

surface to a Plain—Formation of Basins—Dunes of the Desert—

Sand-hills of other regions—Transport and Accumulation of Dust—

Loess, a dust deposit—Lakes and Marshes of the Steppes.

CHAPTER XIII

Land-forms Modified By The Action Of Under-

Ground Water 266

Dissolution of Rocks—Underground Water-action in Calcareous

lands—Karst-regions of Carinthia and Illyria—Effects of Superficial

and Subterranean Erosion—Temporary Lakes—Caves in Limestone

—Caves in and underneath Lava—" Crystal Cellars "—Rock-shelters

—Sea-caves.

CHAPTER XIV

Basins 278

Basins due to Crustal Deformation—Crater-lakes—Dissolution

Basins—Lakes formed by Rivers—^olian Basins—Drainage dis-

turbed by Landslips—Glacial Basins of various kinds; as in Corries,

Mountain-valleys, Lowlands, and Plateaux—Ice-barrier Basins—

Submarine Basins of Glacial Origin.

LIST OF ILLUSTRATIONS

FIGURE

1. Section of Horizontal Strata ....

2. Section across an Anticline

3. Section across Normal Anticlines and Synclines

4. Section across Anticlines and Synclines with Inclined Axes

5. Section across Faulted or Dislocated Strata

6. Section across Unconformable Strata

7. Section across a series of Alluvial Terraces

8. Section and Bird■s-eye View of Colorado Plateau (Powell)

9. Diagrammatic Section across Colorado Plateau

10. Diagrammatic Section showing Stages of Erosion by a River cutting

through Horizontal Strata (after Captain Dutton)

11. Section across Suderoe (Far6e Islands) on a true scale

12. Map of an Island composed of Dome-shaped Strata

13. Section through the Island shown in Fig. 12 .

14. Section of River-valley

15. Enlarged section of a portion of the Island shown in Fig

16. Diagram Map of Plateau of Erosion

17. Section across reduced Plateau of Erosion

18. Longitudinal Section of River Course

19. Section of Escarpments and Outliers

20. Section across the Wealdean Area (Ramsay)

21. Section across Permian Volcanic Basin, Ayrshire

22. Synclinal Hills and Anticlinal Valleys

23. Escarpment Hills and Synclinal Hill

24. Section across West Lomond Hill and the Ochils

25. Synclinal Valley, West of Green River (Powell)

26. Anticlinal Ridge, Green River Plains (Powell) .

27. Isoclinal Folds ......

28. Isoclinal Folds

29. Isoclinal Folds

30. Overfold passing into Reversed Fault, or Overthrust

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