A portion of a geologic map of Wyoming (called the Bull Creek Quadrangle), which you will use to address the questions following it. You will need to zoom in (maybe even 500%) to see all of the details on this map. Note the symbols to the bottom right indicating different structures. After examining the map, address the questions below:
-According to the legend on the side, and what you know about the Geologic Time Scale, is the Phosphoria Formation older or younger than the Chugwater Formation?
-There are quite a few strike and dip symbols on this map. Find one, draw it in the space below, and describe what that symbol indicates about the rock unit below it.
-Find the anticline with the axis that runs right through the R in FOREST. If the anticline symbol was not there, describe how would you know it was an anticline by using the ages of the rocks in the key, and the geologic time scale?
-Which type of fault is most abundant on this map?
-What does this fault type indicate about the dominant type of stress that this area has experienced (tensional, compressional or shear)?
- Attachment 1
- Attachment 2
Portion of the Bull Creek Quadrangle Geologic MapM.L. Schroeder, 1976Rock UnitsgalAlluviumColluviumTalus12Alluvial fan depositsSlump blocksCHMostly compositeslumps and earthflowsderived from rocks ofRAESseveral formationsAQirTr Landslide debrisKbQIOthTh Landslide debrisKS Landslide debrisCTFGlacial depositsTruCamp Davis FormationTbPorphyritic basaltTrRed BedsThHoback FormationSedimentary rocks,UndividedBear River FormationBEARGrimm 1 RamshornGannett Group,-on TR 4010UndifferentiatedStump and PreussSandstonesTwin Creek Limestone614 WHIS WTHRUSTOcOiNugget SandstoneKgChugwater Formation