Think about what you learned about sedimentary rocks. Why would ancient cross-bedded sandstone

beds, as seen in Zion National Park, Utah, be useful to geologists? What will be an ideal response?


There are many things that can be learned from these rock layers. The sandstone is an ancient dune,
having a classic dune structure, so it tells geologists about the environment that was present at the time
the sands were deposited. The cross-bedding indicates the prevailing direction of the wind that formed
the sand dunes. If something is present in the dunes, some fossils or something that can undergo
radiometric dating, perhaps the age of the rock layer can also be determined. It is in this way that
geologists have pieced together the geologic history of the desert Southwest

Environmental & Atmospheric Sciences

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You are in Calgary, Alberta, Canada, 100 km (62 mi) east of the Rockies in January. The current wind is from the north. Looking at a prog for tomorrow, you see that the wind will be from the west, hence tomorrow’s temperature will be ____ today

a. warmer than b. colder than c. the same as d. colder and drier e. the same but more humid than

Environmental & Atmospheric Sciences

Which of the following is a natural factor that doesn't affect Earth's climate?

A) Changes in solar energy B) Reversed magnetic polarity C) Tectonic plate movement D) Variations in Earth's orbit E) Volcanic eruptions

Environmental & Atmospheric Sciences

Governments erect barriers to flows of production factors such as

A) regulations on export of technology. B) immigration laws. C) capital controls. D) all of the above. E) A and C only.

Environmental & Atmospheric Sciences

Most precipitation from thunderstorms originates through the collision-coalescence process

Indicate whether the statement is true or false

Environmental & Atmospheric Sciences