What evidence from volcanic rocks indicates that Earth was much hotter in the past?

What will be an ideal response?


Ultramafic lava flows require mantle temperatures several hundred degrees hotter than our estimates of the present day mantle temperatures. These ultramafic lava flows are all greater than 3 billion years old.

Environmental & Atmospheric Sciences

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The price and availability of chemical fertilizers is strongly influenced by

A. the price of oil on the world market. B. the price a farmer receives for his crop. C. the amount of rain received in any given growing season. D. None of these are correct.

Environmental & Atmospheric Sciences

What reaction occurs when glucose is converted to glucitol?

A) reduction at C-1 B) oxidation at C-1 C) reduction at C-6 D) oxidation at C-6

Environmental & Atmospheric Sciences

Picoplankton number 100 million individuals in a liter of seawater, at all depths in the ocean

a. True b. False

Environmental & Atmospheric Sciences

The chemical composition of all lavas is the same. Indicate whether the statement is true or false

Environmental & Atmospheric Sciences