You are given two igneous rock samples; one is said to be an intrusive (plutonic) rock and the other an extrusive (volcanic) rock. How can you tell which is which?
What will be an ideal response?
Answer: Fast magma solidification usually produces small crystals, while slower crystallization forms larger crystals. The generally fine-grained rocks result from rapid cooling following eruptions from volcanoes. The coarser rocks form from the slow solidification of magma beneath Earth's surface. So, an extrusive rock would be fine-grained with small crystals, while an intrusive rock would be coarse with larger crystals. Also, the accumulation of lava flows and ash deposits produces layers, while plutonic rocks rarely accumulate in layers.
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The diagram on the far left shows the moving particles of a gaseous material within a rigid container. Which of the three boxes on the right best represents this material upon the addition of heat?
A. Box A, because it shows the gas particles rising upon the addition of heat. B. Box B, because it shows the gas particles moving faster. C. Box C, because it shows how the particles expand upon the addition of heat. D. All three of these boxes show accurate representations of what happens to the particles within this rigid container upon the addition of heat.
Which of the following is common during crystallization of magma?
a. felsic minerals crystallize first b. mafic minerals are light and float in most magma chambers c. felsic crystals are heavy and sink in most magma chambers d. all crystals form at about the same time e. none of these
Which of the following methods provides the longest climate record?
A. Tree rings B. Archaeological data C. Lake sediments D. Oxygen isotopes
What is meant by the term neutral atmospheric stability??
What will be an ideal response?