A crater in Mexico’s Yucatan peninsula may be the result of an impact that brought about the extinction of numerous species at the end of the ________ Period.

The reliable paleoclimate record from the Antarctic and Greenland ice cores provides information back to approximately ________ years ago.

Which transport medium carries the largest particles?

As compared to mafic igneous rocks, all felsic igneous rocks ________.

Vesicular is a term used to describe a texture in ________ igneous rocks.

A pre-existing body of gneiss is subjected to heat and forms a melt. Later, the melt cools and crystallizes to form a(n) ________ rock.

The inner edge of a meander, where sediment is deposited, is a(n) ________.

The thickness of oceanic lithosphere is ________.

Continental lithosphere ________.

Ultimately, the base level of a stream valley can be no lower than ________.