Question

Map 3: Four-River Ridge Map Area 300 400- 500 ..Legend (not in order) 600 Shale Limestone Sandstone Gabbro Mudstone 1 Mudstone 2 _-_ Stream Contour interval: 100 m Scale: 1:5000 600 .. 500. 400 Map 3: Four-River Ridge 1. (2 pts) What kind of rocks are found in this map area (sedimentary, igneous, and/or metamorphic)? How many units can you see? 2. (1 pt) Carefully study the relationship between the contour lines and the contact between the limestone and sandstone. What does this tell you about the orientation of these beds? 3. (1 pt) Examine the gabbro unit. What V pattern is formed by the four rivers that cut through this unit? What does this tell you about the orientation of this unit? (2 pts) What is the strike and dip of the sedimentary units in this map area? strike 4. dip- 5. (2 pts) What is the strike and dip of the gabbro dyke? strike- dip (15 pts) Draw a cross-section through the map area along the line between points X and Y. Hint: don't forget to incorporate L.O.T.S.! 6. 7. (4 pts) In point form, describe the geological history of the map area.

Answer 1

The types of rocks found in the area include sedimentary as well as igneous rocks.

There are 5 units of sedimentary rocks while 1 unit of igneous rock is also present.