This page lists 6 geological features that start with X, from “Xenolith” to “Xonotlite”. They include foreign rock fragments, odd crystals, a rock texture, a giant sinkhole, and two minerals. Geologists use them to learn about the deep Earth, trace how rocks formed, and find sources of useful materials such as rare-earth elements and insulation.
Geological features are the rocks, minerals, textures, and landforms that make up the Earth’s surface and interior. Some of them give direct clues about places no one can visit. Xenoliths, for example, carry pieces of the mantle up to the surface.
Below you’ll find the table with the feature, region, characteristics, and description of each item.
Feature: The name of each rock, mineral, texture, or landform, listed alphabetically so you can find a specific entry quickly.
Region: Where you can find each feature, from worldwide occurrences in igneous rocks to single sites, so you know where to look.
Characteristics: The main traits you can use to recognize each feature, such as color, size, texture, or chemical makeup.
Description: A short explanation of what each feature is, how it forms, and why it matters to geologists and industry.
Geological features
| Feature | Region | Characteristics |
|---|---|---|
| Xenolith | Worldwide, in igneous rocks | Foreign rock fragment, embedded in magma, often partly altered |
| Xenocryst | Worldwide, in igneous rocks | Foreign crystal, much larger than surrounding grains |
| Xenomorphic Texture | Worldwide, in igneous rocks | Irregular grain shapes, no well-formed crystal faces |
| Xiaozhai Tiankeng | Chongqing, China | Giant sinkhole, about 660 meters deep, karst landscape |
| Xenotime | Worldwide, in granites and pegmatites | Yttrium phosphate mineral, brown to yellow, rare-earth source |
| Xonotlite | California, USA; Mexico; Scotland | White to gray fibrous calcium silicate mineral, forms in contact zones |