intrusive rocks

Igneous intrusive rocks are generally not divided into Formations.

When erosion removes the overlying rock material, these intrusive rocks are exposed and the pressure on them is released.

This region is more than 2.5 billion years old and is composed of felsic intrusive rocks.

It also occurs in layered ultramafic intrusive rocks.

This is especially critical for komatiite lavas and ultramafic intrusive rocks.

The quartz-porphyries are distinguished from the rhyolites by being either intrusive rocks or Palaeozoic lavas.

The intrusive rocks are inferred to be part of the Mount Kashagnak pluton.

Plutonic or intrusive rocks result when magma cools and crystallizes slowly within the Earth's crust.

Granophyres typically are intrusive rocks that crystallized at shallow depths, and many have compositions similar to those of granites.

It comprises volcanic and intrusive rocks that are calc-alkaline felsic to intermediate in composition.

It is about 16 million years old, situated on the summit of a glaciated mountain ridge made of Late Cretaceous and younger intrusive rocks.

Intrusive rocks are also called "plutonic" rocks, named after Pluto, the Roman god of the underworld.

Included in this type are those associated with intrusive rocks including alaskite, granite, pegmatite and monzonites.

This is particularly prominent in epithermal ore deposits and is associated with alteration zones around many intrusive rocks, especially granites.

The intrusive rocks of the area are composed of three types: subvolcanic massifs, ring intrusions and central plutons.

The interior of the dome structure is dominated by magmatic intrusive rocks, especially east of the North-South trending fault zone.

Xenoliths that originated in the Earth's crust include rich metamorphic rocks and felsic intrusive rocks.

Alignment of tabular minerals in metamorphic rocks, igneous rocks and intrusive rocks may form a foliation.

It occurs within metamorphically altered limestone adjacent to igneous intrusive rocks or within xenoliths.

Several local terms which do not carry official status with the International Union of Geological Sciences have been used for different varieties of the intrusive rocks.

In the southwestern United States, sedimentary, volcanic, and intrusive rocks have been metamorphosed, faulted, foliated, and folded.

Intrusive rocks can also be classified according to the shape and size of the intrusive body and its relation to the other formations into which it intrudes.

Correspondingly, rocks of this kind are also referred to as igneous plutonic rocks or igneous intrusive rocks.

These overlie Late Cretaceous and younger intrusive rocks that form the glaciated mountain ridge on which Crevasse Crag lies.

The volcano is a composite cone built on a high plateau formed from Oligocene-Miocene (Neogene) ignimbrites and intrusive rocks.