How do the contacts and the structural attitudes (strike and dips) compare?
From combing my field observations with other field observations available on the class website most of the strikes appear to be striking generally to the NE – SW.
Also all of the dips are generally to the East with an average dip of 66.67 ranging from 43 – 90 with a median dip of 65.5.
What is the geologic history of the site and how does your map and cross section support it?
From the principle of superposition and original horizontality all of the bedrock layers would have been layed down flat on top of each other at one point in geologic time. Since all of the layers are dipping to the east, assuming a simple single event deformation geologic history and that the layers on not upside down, it can be inferred that the layers are younger to the East. Therefore the relative ages moving from West to
East represent Xmb oldest, Xb, middle and Xq the youngest of the bedrock layers with the Qa unit as overall youngest. After establishing that a possible geologic history can be derived.
It is likely that this region represents Pre Cambrian sub aqueous volcanism followed by a regression. That is, initially basalt was formed underwater from active extrusive volcanism. It is likely that this unit was sub aqueous as directly above it is a younger unit of proto mudstone. Then the volcanism ceased and the region remain underwater in a low energy environment, possibly a marine shallow sea or lagoon brackish laucusrtrian environment that deposited fine muds, silts and clays to later lithifiy into a fine mudstone.
It is more likely that this unit was more fresh or brackish than marine due to the absence of limestone and or marble. Then the body of water regressed as it became a more high energy environment to transport and deposit sand to later lithify into sandstone as the shoreline retreated possibly due to an ice age or increased glaciation elsewhere.
Then over geologic time the region was exposed to intense heat and pressure and metamorphosed the proto basalt to meta-basalt (Xmb), the proto mudstone to Phyllite
(Xb) and the proto sandstone to quartzite (Xq). Also from processes of metamorphism quartz was produced likely from compaction of wet sediments to precipitate silica as this area is rife with quartz veins. Later from regional tectonics these layers were exposed to the surface, uplifted and tilted to their modern day east dipping orientations. Lastly the

region has experienced continuous weathering and erosion to produce the quaternary alluvium (Qa) that is typically deposited in relatively low elevations as sediments are transported fluvially downhill.
My cross section represents this likely geologic history scenario transitioning from Xq, to Xb to Xmb moving from East to West with Qa in relatively low elevations.
Although still an accurate representation, my cross section moves from youngest to oldest in relative age.
How well does the topographic mapping represent the topography?
The way the topographic map represents the topography is not perfect. However for the most part it represents this small area well. The higher elevations in the northwest are represented accurately with the TIN representing the higher elevation in that region which is the hill top. Overall Total Station Survey contact points are not perfect however they match close enough for representation to those observed in the field from processing the data.
What strategies might we have used to improve it?
First of all, more data could have been taken of a larger region to represent more of the topography. Next, a precise aerial swath flyby utilizing high resolution LIDAR to capture the entire region as opposed to one small area could be used to improve topographic data. Also incorporating more GPS data and any other advanced precise mapping technology could help.
Process the topographic data
Total Station Survey Observation Points Represented over air photo:

Total Station Survey Triangulated Irregular Network Elevation Map from observed data:

1.) Final geologic map with semi-transparent overlay over the aerial photographic base and topographic contour intervals.

2) Semi-transparent overlay over the contours calculated from the DEM (traditional map) with Cross Section.

SE
480
A
470
460
450
440
430
420
410
400
0
Qa
87.5
Dreamy Draw 700 m A - A' Cross Section: Danny Foley
Xq
175 262.5
Xb
350
Distance (m)
437.5
Xmb
525 612.5
A'
700
NW
1.
Geologic map over air photo base

2.
Geologic map over contours

3.
Best version of the topographic map with transparency to air photo.

4.
rectified field map and supporting maps of interest

Field Observations:

Easting Northing
403230.00 3714205.00
403233.00 3714258.00
403208.00 3714283.00
403147.00 3714389.00
403270.00 3714420.00
403233.00 3714199.00
Strike
44.00 74.00 foliation S&D of Xb
20.00 84.00 foliation S&D of Xb
30.00
55.00
59.00
47.00
Dip Description
70.00 foliation S&D of Xb
61.00 foliation S&D of Xmb
66.00 foliation S&D of Xb
66.00 contact of XQ 1.5m wide fault zone, foliation
403211.00 3714269.00 212.00 90.00 Xmb dipping from 80 to 110
403419.00 3714413.00
403339.00 3714164.00
36.00
46.00
90.00 Xmb dipping from 80 to 100
67.00 Contact of Xq and Xb, zone 1.5m wide
403384.00 3714236.00 162.00 43.00 Contact of Xq and Xb
403343.00 3714298.00 233.00 80.00 Contact of Xq and Xb
403344.00 3714450.00
403246.00 3714199.00
43.00
43.00
80.00 Foliation in Xb
61.00 Xq, bedding or joint planar surface
403230.00 3714265.00
403203.00 3714461.00
403224.00 3714448.00
403243 3714195
403236
403208
403167
403147
403188
403161
403195
3714218
3714271
3714369
3714950
371449
371442
3714421
50.00
37.00
37
15
15
22
31
52
74
345
75.00 Xq,foliation
60.00 Xb SE, Xmb NW
55.00 75.00 Xq SW, Xb NW
55 Xq: Weathered, dark, good view of Phx & 51
65 Xb: cleavage fractures, foliation, lineation
65 Xb: large outcrop, course ~ mm elongated crystals
56 Xb:silver,no crystals visible,10 cm quartz vein 10 m W
44 Xmb: fine , no visible crystals, not shiny, dull light green,
64 Xb: no visible crystals, blue, not as shiny as previous
45 Xmb
64 Xq
VZ
VZ
VZ
VZ
Geologist
SR
TA
SR
SR
SR
MM
SK
SK
DE
DE
DE
DE
DF
DF
DF
DF
DF
DF
DF
DF