LABORATORY TEN –GEOLOGIC STRUCTURE, MAPS, AND BLOCK DIAGRAMS

Laboratory Manual in Physical Geology by The American Geological Institute (AGI) and the National Association of Geoscience Teachers (NAGT); Richard M. Busch, Editor; 6th Edition, 2003.

STRUCTURAL GEOLOGY

STRESSSS / STRAIN

GEOLOGIC MAPS

FORMATIONS, MEMBERS, CONTACTS

SYMBOLS (Figure 10.3, p. 171)

GEOLOGIC CROSS-SECTION

BLOCK DIAGRAMS

ATTITUDE (ORIENTATION) OF ROCK UNITS

STRIKE

DIP (ANGLE)

DIP DIRECTION

Symbol |- ₂₅

UNCONFORMITIES

(DISCONFORMITY, ANGULAR UNCONFORMITY, NONCONFORMITY)

FAULTS

DIP-SLIP

NORMAL

REVERSE

THRUST

STRIKE-SLIP

RIGHT-LATERAL

LEFT-LATERAL

FOLDED STRUCTURES

ANTIFORM / ANTICLINE (Position of axial plane: Upright, inclined, overturned, recumbent)

SYNFORM / SYNCLINE (Position of hinge line: Non-plunging, plunging)

MONCLINES

DOMES

BASINS

RULES FOR INTERPRETING GEOLOGIC MAPS (Figure 10.13, p. 177)

HORIZONTAL STRATA. Contacts will parallel contour lines.

INCLINED STRATA

DIRECTION OF DIP = RULES OF THE Vs

FOLDED STRATA

NON-PLUNGING = Roughly parallel band

PLUNGING = Winding or curved bands

FAULTED STRATA

TRACE

STEEP FAULTS (Straight traces)

GENTLE FAULTS (Irregular traces)

VARIATION IN OUTCROP PATTERNS

WIDTH OUTCROP