What does a porphyritic texture indicate about the history of an igneous rock?
What will be an ideal response?
Porphyritic texture tells a more complicated cooling history of the magma/lava. A melt that has already formed large crystals at some depth will continue to cool and crystallize more rapidly if it then erupts at surface. The end product is a rock with two distinct crystal sizes in it, which is porphyritic texture.
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The ecological economic paradigm argues that the environment encompasses the economy because the environment is essential to provide
A) the energy necessary to run our homes and factories. B) solar energy needed for plants and to light our environment during the day. C) transportation along highways, railways, rivers, and oceans. D) vital raw materials and ecosystem services and absorb wastes.
Rip currents are strong currents parallel to the coastline; swimmers can easily avoid them by swimming toward shore
Indicate whether the statement is true or false
Which of the following atmospheric constituents has the least ability to absorb heat on a per-mole basis?
A) Carbon dioxide (CO2) B) Methane (CH4) C) Nitrous oxide (N2O) D) Chlorofluorocarbons (CFCs) E) Ozone (O3)
In a nuclear power plant, the amount of electricity generated is regulated by ________
A) moving control rods into or out of spaces between the fuel rods B) moving the nuclear fuel in and out of water C) releasing surplus heat out of cooling towers that are always part of nuclear power plants D) the Federal Trade Commission E) changing the water levels that surround the control rods