Name: Course/Section: Date: Learning GOAL You will visualize, analyze, and interpret geologic structures in block diagrams. For each block diagram in Fig. A10.6.1: 1. Complete the diagram so that contact lines between rock formations are drawn on all sides. 2. Add symbols (Fig. 10.4) to indicate the orientations of all structures. 3. On the lines provided after each of the block diagrams, write the name of the geologic structure represented in the diagram. S M D M D S A. Complete top and side. Add appropriate symbols from Fig. 10.4. What type of fold is this? B. Complete top and side. Add appropriate symbols from Fig. 10.4. What type of fold is this? D S 0 M C. Complete top and side. Add appropriate symbols from Fig. 10.4. What type of fold is this? 301 the 50 PP M D S D M D. Complete top of diagram. Add appropriate symbols from Fig. 10.4. What geologic structure is this? T E. Complete the sides of the diagram. What geologic structure is this? F. Complete the sides of the diagram. What geologic structure is this? Figure A10.6.1 s c c c c c c c c c c 24 78 84 47 63 Horizontal bed Strike of vertical bed Strike and dip direction of inclined bed. Dip line is 1/5 length of strike line. Strike, dip direction, and dip angle of inclined bed. Overturned bed. Dip direction is to the SE Strike, dip direction, and dip angle of an inclined joint Strike, dip direction, and dip angle of an inclined foliation Trend and plunge angle of a lineation. Contact; solid where known, dashed where inferred, dotted where covered by soil or sediment Unconformity D Devonian S Silurian U Fault; solid where known, dashed where inferred, dotted where covered by soil or sediment 60 Dip direction and dip angle of inclined fault Vertical fault Sense of vertical displacement (up, down) along fault Normal fault with bar and ball symbols on the down-dip (hanging-wall) side Reverse fault with rectangles on the down-dip (hanging- wall) side Thrust fault with triangles (barbs) on the down-dip (hanging-wall) side Map Symbols Indicating Age J Jurassic TR Triassic Right-lateral strike-slip fault Left-lateral strike-slip fault Symbols for Faults on Cross Sections A/T AT Strike-slip fault; A means "away" and T means "toward" Strike-slip fault; circle with X or cross moves away, circle with dot moves toward Strike-slip fault; circle with cross moves away, circle with bar moves toward Normal fault with displacement indicated by half arrow symbols Reverse fault with displacement indicated by half arrow symbols Q Quaternary N Neogene Monocline with arrow pointing down the step Synclinal bend of a monocline; short arrow is on the steeper limb Anticlinal bend of a monocline; short arrow is on the steeper limb Anticline, with the longer curve along the ground-surface trace of the fold axis Syncline, with the longer curve along the trace of the fold axis Plunging anticline with trend of plunging fold axis indicated by the arrowhead on the trace of the fold axis Plunging syncline with trend of plunging axis indicated by the arrowhead on the 中 axial trace Overturned anticline Overturned O Ordovician € Cambrian p€ Precambrian P Permian PE Paleogene P Pennsylvanian K Cretaceous M Mississippian syncline Figure 10.4 Structural geology symbols and time-related abbreviations used on geologic maps. These map symbols agree with USGS standards for geologic maps.