Pyroclastic Texture Igneous Rock

Igneous textures include the rock textures occurring in igneous rocks igneous textures are used by geologists in determining the mode of origin igneous rocks and are used in rock classification.

Pyroclastic texture igneous rock. Magma can cool to form an igneous rock either on the surface of the earth. Examples of aphanitic rocks the two images below show a hand sample and a thin section of aphanitic textured rocks. Pyroclastic texture results from the explosive fragmentation of volcanic material including magma commonly the light frothy pumice variety and glass fragments called shards country rock and phenocrysts. Introduction to igneous rocks.

And κλαστός meaning broken are sedimentary clastic rocks composed solely or primarily of volcanic materials. An igneous rock is any crystalline or glassy rock that forms from cooling of a magma. There are six main types of textures. Where the volcanic material has been transported and reworked through mechanical action such as by wind or water these rocks are termed volcaniclastic.

Phaneritic vesicular aphanitic porphyritic poikilitic glassy pyroclastic equigranular and spinifex. Other articles where pyroclastic texture is discussed. Pyroclastic rocks or pyroclastics are clastic rocks composed solely or primarily of volcanic materials where the volcanic material has been transported and reworked through mechanical action such as by wind or water these rocks are termed volcaniclastic commonly associated with unsieved volcanic activity such as plinian or krakatoan eruption styles or phreatomagmatic eruptions. Aphanitic texture consists of small crystals that cannot be seen by the eye with or hand lens.

Phaneritic aphanitic porphyritic glassy pyroclastic and pegmatitic. There are six main types of textures. Phaneritic aphanitic porphyritic glassy pyroclastic and pegmatitic. A magma consists mostly of liquid rock matter but may contain crystals of various minerals and may contain a gas phase that may be dissolved in the liquid or may be present as a separate gas phase.

A rock with a pyroclastic texture is termed a tuff if the largest fragments are less than 2 5 inches long a volcanic breccia if the fragments are larger. Introduction to igneous rocks an igneous rock is any crystalline or glassy rock that forms from cooling of a magma. Each kind of texture has a variety of different characteristics that make them unique. A magma consists mostly of liquid rock matter but may contain crystals of various minerals and may contain a gas phase that may be dissolved in the liquid or may be present as a separate gas phase.

The entire rock is made up of small crystals which are generally less than 1 2 mm in size. Properties of igneous rock textures. Fragments less than 2 millimetres in size are called ash and the rock formed of these is. A pyroclastic texture shows a mixture of rock fragments pumice and volcanic ash.

The ash is very fine grained so only the rock fragments and pumice are identifiable. What determines igneous rock texture. There are nine main types of igneous rock textures.