(Solved): Mid-Continent Gravity Anomaly This map shows variations in the gravity field in the central part of ...
Mid-Continent Gravity Anomaly This map shows variations in the gravity field in the central part of the United States. Exceptionally high gravitational field is shown in red, yellow shows normal gravity, and blue shows a low gravity field. a. What is the length and width of the mid-continent gravity high? How does the size of this feature compare with the East African rift valleys and the Rio Grande Rift? b. The rock sequence along the Keweenawa Peninsula of northern Michigan consists of a sequence of basalt and conglomerate nearly 80,000 feet thick. These are shown with a stipple pattern. How are these rocks related to the midcontinent gravity anomaly? c. The density of common rock is as follows: granite
=2.6, basalt
=3.0, sedimentary rocks
=2.5, gneiss and schist
=2.6. What rock type likely exists in the mid-continent gravity high in Kansas, Iowa, and Minnesota? d. Draw a cross section across the mid-continent gravity high showing the structure and rock types that could produce this gravity anomaly.
