Figure G-27 is a geologic map and structure section from the Inyo Range of eastern California. Using complete sentences, describe the history of principal stress orientations in this area. What can you say about the specific time periods that the variously oriented stresses were in effect? Is there any evidence that shear surfaces were controlled by anything other than the orientation of the principal stresses? Explain.

Fig. G-27

A. a A 8800 8000 7200- 6400 p 5600 4800+ 4000- PE 3200 2400 b PE AZI pe Pe PE 3 pe PEPPE PE 0 0 D-M ND-M 1 2 D-M D-M 3Km D-M D.M+ D-M. 3 Miles D-M DE HA D-M D-M D-M D.M. D-M D-M D-M Devonian-Mississippian sedimentary rocks Cambrian sedimentary rocks pe Precambrian -A' sedimentary rocks Normal fault Thrust fault (teeth on upper plate) Fault Bedding plane