Objective:  Create an underground geologic map from the data provided. 

Procedure:

1.  The adit is oriented north-south.  Draw the continuation of the base lines parallel to the edge of the map.  The scale of the map is 1 inch = 10 feet; the trench is 90 feet long.  Place tick marks every inch labeled 0, 10, 20, 30.......80, 90 feet.  The data in the table below is tied to footage marks along the base line;  the footages refer to points along the center of the floor of the adit.

2.  The adit is 10 feet wide.  Since the adit is oriented north-south, show two lines parallel to each other and the edges of the page, and one inch apart, down the center of the page.  These lines represent the corners of the adit (sometimes called “toes”).  These lines should be the same length as the base line.  Show tick marks along each of these lines matching the tick marks of the base line.

3.  The footage designation for each data point refers to the point along the adit floor.  The floor represents a “map view” (vertical view downward), and the sides adjacent to the floor represent a view straight towards the respective sides, ie, the mapping to the right of the right toe represents a view of the vertical wall forming the right side of the adit.  The floor will show the strike direction of the contacts, faults, joints, or other planar features, and the map of the walls on each side of the floor map will show the dip of the same features.  Show the strike and dip symbols on the floor.  Use color pencils or patterns to show the units graphically on the map, and label each unit with the unit designator.  Also put the unit designator in the boxes on the left side of the map and color the boxes with the appropriate colors.  Use heavy lines for faults and regular weight lines for regular or intrusive contacts.  Use small triangles to show fault breccia.  Strike directions are given in azimuths.

S & D = Strike and Dip             deg. = degrees

Footage or Interval	Geologic Feature	Unit Designator
0 ­ 3	Gray marble	gm
3	Contact with tan quartzite:  Contact S & D: 100 @ 20 deg. SW
3 ­ 30	Tan quartzite	tq
20 ­ 25	Joints:   S & D: E-W @ 45 deg. South
30	Fault:   Fault plane S & D: E-W @ 45 deg. South 3 inch wide breccia zone
30 ­ 37	Calcareous quartzite	cq
37	Contact with Rhyolite Tuff:   Contact S & D: 100 @ 30 deg. SW
37 ­ 48	Rhyolite Tuff	rt
48	Intrusive contact:   Contact S & D: E-W @ 90 deg.
48 ­ 70	Coarse-grained Biotite Granite	bGr
60 - 62	Vertical dike of Fine-grained Muscovite Granite cutting bGr Strike of dike: 135	mGr
55 - 65	Joints:  Set #1 S & D: 45 @ 70 NW.   Set #2 S & D: 90 @ 90 deg.
70	Intrusive contact:   Contact S & D: E-W @ 70 deg. N	mGr
70 ­ 80	Fine-grained Muscovite Granite
80	Intrusive contact:  Contact S & D: 40 @ 90 deg.
80 - 82	Skarn	sk
82 ­ 90	Gray marble	gm
86 ­ 88	Basalt dike cutting sk.  Dike S & D: 100 @ 40 deg. N	bs

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