Diagram showing schematically the formation of a slump in a valley within the basalt area. 1. Basalt beds; 2. Dikes; 3. Sedimentary layers; 4. Ice; 5. Rockslide (slump). Iceland.

Development of a broad coastal plain. A. Initial stage; plain recently emerged. B. Mature stage; cuestas and lowlands developed. C. Late mature or old age stage; relief very low. Srahler, 1960. p. 450.

A simple alluvial fan. Strahler, 1960, p. 359.

Rock breakup takes various forms. Granular disintegration, exfoliation, joint-block separation, shattering. Strahler, 1960, p. 312.

A drainage system consists of many small basins, each adjusted in size and shape to the magnitude of the stream it serves. Streams shown by solid lines; divides by dashed lines. Strahler, 1960, p. 375.

Slump rocks rotate backwards as they slide from a cliff. Strahler, 1960, p. 323.

Four types of rocks and their topographic expression. Normal fault; reverse fault; strike-slip fault; overthrust fault. Strahler, 1960, p. 475.

A trellis drainage pattern on folds. This resembles the trellis drainage pattern of eroded dipping sediment (slide Box XII-15), but opposing sets of tributaries are shorted and of more equal length than on cuesta topography. Strahler, 1960, p. 473.

Diagram showing stages in the development of a mountainous dome. Strahler, 1960, p. 463.

Dirt Hills ice thrust area, general view. Behind brick plant at Claybank. Saturday, October 1, 1960.

Same as slide XII-43, closer view to show the outcrop. Sunday, October 2, 1960.

Wandering the north magnetic pole through geologic time. although students of ancient rock magnetism regard this path as fairly well established, there is no conclusive proof that the geographic pole followed the same path or that the continents maintained their same positions during this lengthy period. Notice also that there are no signs of frigid conditions or glacial action in northeastern Asia during the periods when the pole was supposed to be in that vicinity. Stokes, 1960, p. 168.

Earthquake epicentres (black dots and circles) in the middle of the Atlantic almost fall within a narrow belt that coincides with rift valley of the mid-Atlantic Ridge. Open circles indicate strongest earthquakes; solid dots represent weaker earthquakes. Heezen, 1960.

Confined and unconfined aquifers. Artesian wells may be flowing or non-flowing depending on whether the pressure surface is above or below the ground surface. (A) Wells in an unconfined aquifer. (B) Artesian wells in a confined artesian aquifer. Zumberge, 1958, p. 135.

Hoodoos. Hoodoo Valley, Banff. G.S.C. Photo