McAfee SECURE sites help keep you safe from identity theft, credit card fraud, spyware, spam, viruses and online scams

Home » Geology Dictionary

Geological Terms Beginning With "X"



For Terms Beginning With Other Letters Please Click Below

A     B     C     D     E     F     G     H     I     J     K     L     M     N     O     P     Q     R     S     T     U     V     W     X     Y     Z

Xenoblast

Xenoblast

A crystal that has grown in a rock during the process of metamorphism and which has not developed its characteristic crystal faces because of space limitations. These crystals typically have boundaries that are straight or that conform to the shape of adjacent crystals. The photo shows quartz and feldspar grains in a gneiss.

Xenolith

Xenolith

A preexisting rock that has been incorporated into magma without melting. When the magma crystallizes the preexisting rock fragment is known as a xenolith.

Xerophyte

Xerophyte

A plant that can survive in a very dry location or climate because it has a well-developed means of storing and conserving water. The image shows a group of cacti living on a desert floor.

X-ray Diffraction

X-ray Diffraction (XRD)

A technique used to identify minerals and other crystalline materials by bombarding them with X-rays. Planes of repetition within the atomic structure of the mineral diffract the X-rays. The pattern of diffraction is unique for each mineral structure and can be used for identification. This method of identification is much more reliable than hand-specimen identification and is used when hand-specimen identification is not possible or difficult.

X-ray Diffractogram

X-ray Diffractogram

A printed or digital record of an x-ray diffraction analysis. It shows the angle of diffraction on the horizontal axis and the intensity of diffraction on the vertical axis. Peaks on the diffractogram are characteristic of the material being examined and can be compared with reference diffractograms to identify minerals and other crystalline compounds.

X-ray fluorescence

X-ray Fluorescence (XRF)

A technique used to determine the elemental composition of a specimen by bombarding the material with x-rays. The x-rays excite the atoms in the specimen causing them to emit x-rays of a longer wavelength. These are detected by the analytical equipment and on the basis of comparison with known standards the elemental composition of the specimen is determined.

xyloid coal

Xyloid Coal

A type of lignite coal that displays the fibrous structure of the wood. Also known as "xyloid lignite".

xyloid coal

Xylopal

An opalized wood. Forms when common opal infills the cavities and replaces the organic material of a piece of wood. Sometimes the wood grain or cellular details of the original wood can be seen..

A     B     C     D     E     F     G     H     I     J     K     L     M     N     O     P     Q     R     S     T     U     V     W     X     Y     Z



Find it on Geology.com




More from Geology.com


Plate Tectoncs
Zoom in on Plate Boundaries: See the details of plate tectonics in satellite view.
Types of Volcanic Eruptions
Types of Volcanic Eruptions: A description of the most common eruption types.
diatomite
Making Beer With Rocks - Do you know which fossiliferous rock is used to make beer?
uses of gold
The Many Uses of Gold: Unique properties make gold one of the most useful metals.
Fossils
Fossils: Learn about fossils and fossil discoveries around the world.
Organic Gems
Organic Gems are gems formed from or by plants or animals. They might also be fossils.
Meteorites
Meteorites - Rocks that were once parts of planets or large asteroids.
Mount Cleveland
Mount Cleveland is an active volcano in the Aleutian Islands and a threat to air traffic.



© 2005-2014 Geology.com. All Rights Reserved.
Images, code and content of this website are property of Geology.com. Use without permission is prohibited. Pages on this site are protected by Copyscape.