The theory of drifting continents according the Wegener. One protocontinent, Gondwanaland, existing through most of geologic time (A), but later broke into "blocks: (B), and "drifted" to their present positions (C). Dotted areas on continents are areas formerly covered by shallow seas. Zumberge, 1958, p. 65.

Delta. The rapid growth of some deltas is represented by the delta of the Po River, Italy. The entire land area on the map is within the delta area. The stippled section of the delta was built between 1559 and 1869.Leet and Judson, 1958, p. 184.

The quahog, 'Venus mercenaria' Linne, showing how age may be reckoned by counting the more prominent growth lines. Three and a half years old; three inches long. At the same time each year a notch is filed into the edge of the shell.

The principal parts of a slump type landslide. Putnam, 1964, p. 255.

Arcs. The primary arcs or elements of the two active orogenetic belts of the continental fracture system. Jacobs et al., 1959, p. 291.

The pool of Geysir with Bob Clark, New Zealand, in background. August 9, 1960.

Illustration of the Fishing Lakes, Qu-Appelle Valley in 1858. Copied from a book. Pioneer Geologists in Saskatchewan.

The evolution of elephants showing the Mastodon and Mammoth.

The Bering Straits between North America and Asia, showing the shallow, submerged shelf that would become land with a drop of sea level of only 150 feet. During the Ice Age and at various times during the Tertiary Period, this land bridge was open to migrations between the Americas and Eurasia. In many ways, it is the most important land bridge on the earth. Land areas are in grey, water over 150 feet is in black and water less than 150 feet deep in white. (Stokes, 1960, p. 405).

The bedrock formations of Iceland. Palagonite Formation = Moberg Formation Older Series = Old Grey Basalts. Younger Series = Moberg Mountains and Young Grey Basalts

The Alaskan-Siberian land bridge wich functioned as a migration route along which an interchange of animals took place between Asia and North America during the Pleistocene. (Zumberge, 1958, p. 360).

Tertiary-Quaternary volcanic area northeast of Arequipa showing acidic (white) and basic (dark on top) volcanics.

Tertiary gravels. Cypress Hills formation. West of Wymark, Sask.