Student Name: Grade:
Physical
Geology 101 Laboratory
Geology Maps
Introduction
& Purpose: The purpose of this lab is to
both learn and apply the concepts of
structural geology to reading and interpreting geologic maps. The terms and concepts of geologic
structures, the application of structural geology to mountain building events, and
the terms,
concepts, and techniques used to create and interpret geologic maps will be
discussed. The
usefulness of geologic will also be highlighted and discussed.
The objective of this laboratory exercise
is to become successful at applying the principles learned
in the topographic and structural geology labs towards the analyzing geology maps for solving surface and subsurface structural and geologic relations that may include a record of igneous, metamorphic, and sedimentary rock-forming events, mountain building deformation, and surface erosion.
Part I –
Introduction:
A
geologic map is a greatly scaled-down, two-dimensional abstract representation
of the surface geology, structure, and relief of a geographic region of Earth,
or even another terrestrial planet. A
geologic map typically includes most information found on a topographic map,
but most importantly, includes color-coding regions and symbols that denote
rock units, contacts, and other structural information. Additionally, all the geologic color-coding
and symbols are explained in the legend on a geologic map, including
topographic and cardinal information.
Directions: Do a general examination of the entire geologic map
of the Devil’s Fence Quadrangle. Carefully
examine the various rock units represented by the colored regions and related
map symbols on the map that portray the surface geology of this area in
1) Where in
2)
What is the magnetic declination for this region? ____________________
3)
What is the map and verbal scale for this map?
________________________________________
4)
What is the contour interval of this map? ___________________
5)
How many square miles does this map cover? _______________________
6)
What are the minimum and maximum elevations for this area? Min = ________ Max = _______ 7)
What is the total vertical relief for this area? __________________
8)
Would you consider this area gentle, or rugged, in relief? ____________________________
9)
Does the topography (location and orientation of ridges and valleys) correspond
to the location and orientation of geologic rock units _____ Describe an example ______________________________
10)
What topographic feature does Devil’s Fence correspond with?
_________________________
12) What is the total range in age for the various rock types found on the map? ___________ years
13) Name the youngest rock unit exposed in this area? __________________________
14) Where is this youngest rock unit located on the map?
__________________________________
15) Name the oldest rock unit exposed in this area? __________________________
16) Where is this oldest rock unit located on the map? ____________________________________
17) This rock unit forms the center of what general type of deformational geologic structure, such as a fold or fault? (hint: notice the upside down “V” shaped pattern of rocks) _________________.
18) If you wrote down “fold”, is it a syncline or an anticline? ______________________
19) What information did you use to tell whether it was a syncline or an anticline? _______________
________________________________________________________________________________
20) If it is a fold, is it a horizontal or plunging fold? __________________________
21) If plunging, then which direction is the fold plunging? Determine the bearing of fold axis _______
22) Find the
23) If you wrote down “fold”, is it a syncline or an anticline? ______________________
24) What information did you use to tell whether it was a syncline or an anticline? _______________
________________________________________________________________________________
25) If it is a fold, then is it horizontal or plunging fold? __________________________
26) If plunging, then which direction is the fold plunging? Determine the bearing of fold axis _______
27) How many distinct folds are
found in this geologic map? _____________
28) Which two compass directions did
the deviatoric stresses come from to cause the
folding? _____
29) What type of rock makes
up the
30) Determine the timing
between the intrusion of the
Part II - Geologic Map Laboratory Reflection
Write a short reflection (about a paragraph length) about your experience in working with geologic
maps, and cross-sections. Include what you learned from this laboratory; what was interesting; the problems and challenges you encountered; and how this lab was designed (the good and/or bad).