extrusive

Most are volcanic and extrusive in nature, rather than tectonic.

Basalt is a common gray to black extrusive volcanic rock.

The degree to which these practices took place was based off the two modes of social death, intrusive and extrusive.

It is an extrusive rock that is very resistant to erosion.

It was a path-breaking work which explored the extrusive aspect of European history.

Because extrusive rocks make contact with the atmosphere they cool quickly, so the minerals do not have time to form large crystals.

The first, extrusive, is above the Earth's crust.

This is to be contrasted with extrusive rocks.

Extrusive apparatus is surrounded by a basket of tubules.

As might be expected, they show structures intermediate between those of extrusive and plutonic rocks.

Extrusive rock is produced in the following proportions:

Moments later, another blast struck a glancing blow, shearing off an extrusive wing element.

There are two types of vulcanicity: intrusive and extrusive.

A discrete extrusive volcanic body distinguishable by texture, composition, or other objective criteria.

It is composed of trap rock, also known as basalt, an extrusive volcanic rock.

Dolerite dykes intruded the extrusive volcanic rocks around 563 million years ago.

This is an extrusive igneous rock.

Small intrusions occur both in association with larger forms, and with extrusive igneous phenomena.

Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock.

The texture is often found in extrusive aphanitic, or glassy, igneous rock.

These mostly pastel-colored extrusive rocks still blanket much of the high areas of central and southwestern Utah.

This suggests that these intrusive and extrusive rocks are coeval and share a common source.

The extrusive rock is composed of breccia and conglomerate.

The volume of extrusive rock erupted annually by volcanoes varies with plate tectonic setting.

The first, which sampled the upper part of the extrusive lava layer, had to be abandoned at 500 m because of technical problems.