Alessandro Grippo, Ph.D. A key to labs 16 and 17 (Earth History) 16 - Mountain Belts of North America 17 - The Interior Plains and Plateaus   16 - Mountain Belts of North America Last Updated  •  December 2, 2016     THE SAN ANDREAS FAULT question 1, page 235 The streams, the most recent feature in the image, are interrupted by the San Andreas Fault question 2, page 235 A right-lateral strike-slip fault APPALACHIANS question 1, page 237 skipped skipped skipped skipped question 2, page 238            skipped question 3, page 239 Three times. Because there are three different thrusts stacked on top of each other About 2.8 miles of thickness Because we are moving from the foreland onto the undeformed craton Because they are outside the fold-and-thrust deformation belt that develops on the sides of the mountain chain question 4, page 239            skipped THE CORDILLERAN OROGENIC BELT: PACIFIC RANGES question 1, page 240            skipped question 2, page 240            skipped question 3, page 241            skipped THE CORDILLERAN OROGENIC BELT: COLORADO AND WYOMING question 1, page 243            skipped MAP INTERPRETATION OF MOUNTAIN BELTS            skipped   17 - The Interior Plains and Plateaus Last Updated  •  December 2, 2016     MAJOR STRUCTURAL FEATURES Questions were skipped, but you should know this paragraph INTERPRETATION OF THE GEOLOGIC MAP OF NORTH AMERICA            skipped INTERPRETATION OF GEOLOGIC STRUCTURE SECTIONS Michigan Basin, Illinois Basin, and Adjoining Domes            skipped The Appalachian Foreland            skipped Midcontinent Region and the Cordillera Foreland            skipped Submergence of the Ozark Dome question 1, page 254 Draw the unconformity The lowermost strata disappear, or pinch out, against the unconformity when moving from right to left A non-conformity (sedimentary rocks on top of the crystalline basement) question 2, page 254 You can easily see a pattern of transgression when you notice that the first Formation deposited above the crystalline basement is a sandstone (Lamotte Fm.), followed by limestone (Bonneterre Fm.). From Figure 17.5, page 255, you can also see that the on lap, or progressive advancement of these marine layers, onto the continent is gradual,layers pinch out, as seen in question 1 above, part b. The profile of the unconformity is not flat, and it represents an ancient mountain that was slowly surrounded by marine layers as the sea kept on rising. question 3, page 254 According the inside cover Geologic Time Scale, the Cambrian extends from 542 to 488 million years ago, for an overall duration of 54 million years. One third of 54 million years is 18 million years. Back to Top | Back to Labs | Back to Home Page © Alessandro Grippo, since 1994 Los Angeles, California