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. Most diamonds found at or near Earth's surface are in xenoliths ripped from the mantle during the deep-source volcanic eruption that delivered them up into the crust.

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 mineral identification. This method of identification is much more reliable than hand-specimen identification and is used when hand-specimen identification is not possible, difficult, or has produced questionable results.

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. X-ray fluorescence can be especially valuable because it can be used as an aid in identifying materials that are not crystalline and thus cannot be identified by x-ray diffraction.

xyloid coal

Xyloid Coal

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

Dictionary of Geological Terms   Dictionary of Geological Terms - Only $18.95

All scientific disciplines have an essential vocabulary that students and professionals must understand to learn and communicate effectively. A geology dictionary that is used regularly is one of the most important tools for developing professional competence. A good dictionary should be on the desk of every geologist and within easy reach. This dictionary is compact and inexpensive at only $18.95. More information.
xylopal

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


Sliding Rocks
Sliding Rocks Mystery: What causes these rocks to slide across a Death Valley playa?
Gfeller Leather Cases
Gfeller Leather field cases, hammer holsters, lanyards, field belts, acid bottle cases, more.
Gemstones of the World
Gemstones of the World - A book by Robert Schumann. Over one million copies sold.
World Globes
World Globes - A nice selection of globes for students, schools, homes and offices.
Geology of Gems
Geology of Gems - The first comprehensive book on the geology of gem deposits.
Sea Level Rise Map
Sea Level Rise Map: A Google map that shows where flooding will occur as sea level rises.
K2 Granite - aka K2 Jasper
Azurite Granite ? A white granite with blue orbs of azurite. A new material from Pakistan.
Apatite
Apatite produces gemstones with vivid colors and is popular with collectors.





© 2005-2016 Geology.com. All Rights Reserved.
Images, code, and content on this website are property of Geology.com and are protected by copyright law.
Geology.com does not grant permission for any use, republication, or redistribution.
Images, code and content owned by others are marked on the pages where they appear.