Homework Assignments - Geol of Western National Parks

Name:_________________________

HW1 – Stratigraphy & Geologic Time

Reference – http://homepage.smc.edu/grippo_alessandro/gss1.html

1) James Hutton used the term _________________to compare present-day rock cycle to ancient rock cycles; the geologic processes operating today were the same ones operating in the past.

2) The ___________________ states that in a sequence of sedimentary rock layers, the bottom layers are older than the top layers; the bottom layers were deposited first.

3) Nicholas Steno, a Danish physician living in Italy in 1669, proposed that the Earth’s strata accumulated with three basic principles. List Steno’s three principles.

4) This principle states that the oldest fossils in a series of sedimentary rock layers will be found in the lowest layer.__________________________

5) The broadest division of geologic time is the ________________

a. epoch b. stage c. eon d. era e. period

6) ________________ are 3 astronomical cycles responsible for climate change on Earth by altering the amount of solar radiation our planet receives from its star.

Building North America

Reference – https://www2.nau.edu/rcb7/Text_WUS.html

7) The use of fossils in stratigraphy is referred to as _________________. If the original organism is short lived and abundant over a large area, it is called a/an ______________.

8) About 1.1 Ga (billion years ago), North American was part of the supercontinent of _______________. The continents adjacent to what was then the western margin of North America were __________ and ______________.

9) During Cambrian time (~510 Ma), what was happening along the western edge of North America? What types of rocks or sediments were being formed/deposited?

10) In Middle Ordovician time (~470 Ma), what was the name of the landmass approaching western North America? ________________

11) In Middle Ordovician time (~470 Ma), what geologic processes were occurring in what is now southern Utah and Northern Arizona? _____

a. mountain building d. sediment deposition by rivers

b. sediment deposition by wind e. sediment deposition in a shallow sea

c. sediment deposition in deep ocean

12) What was the Antler Orogeny (describe the geologic process/es)?