gabbro
IPA: gˈæbroʊ
noun
- (petrology) Originally, a kind of serpentine; now generally a coarsely crystalline, igneous rock consisting of lamellar pyroxene and labradorite.
Examples of "gabbro" in Sentences
- Above the ridges are topped by hard gabbro.
- Boreray is formed of a breccia of gabbro and dolerites.
- Igneous rocks, including granite and gabbro, are common.
- One of these intrusions contained the gabbro and diorite.
- The landscape is rocky with basalt, gabbro and sandstone.
- This is particularly true if a gabbro is in fact a gabbro.
- The island is formed of a breccia of gabbro and dolerites.
- The crystallized magma forms new crust of basalt and gabbro.
- The orientation of the layers of gabbro in Skarstind is uncommon.
- Pyroxene and feldspar are the major minerals in basalt and gabbro.
- Cumulate gabbros are more properly termed pyroxene plagioclase orthocumulate.
- Dark-colored serpentine and gabbro also are found interstratified within the shales.
- Like labradorite and anorthite, it is a common constituent of basic igneous rocks, such as gabbro and basalt.
- To illustrate the operations, I will describe a specific case, viz. that of grinding the section of "gabbro"'above described, for microscopical purposes.
- In the southwest the underlying bedrock is granite and gneiss, in the north and east there are magmatic rocks including reddish rapakivi granite, gabbro and anorthosite.
- Besides the dyke swarms, the northern section is composed mainly of serpentinised peridotite and gabbro masses, although there are small areas of extrusive volcanic rocks.
- Some areas within this region have more alkaline soils, such as the Iredell series, formed over diabase, diorite, or gabbro, and may be associated with areas once known as blackjack oak prairies.
- Mount Warning itself represents the original neck of the volcano which, being more resistant (comprising syenite, gabbro and monzonite) than the surrounding basalt and rhyolite, remains as an isolated plug.
- The higher elevations of the Nicobars often contain serpentine and gabbro formations, whereas at lower elevations Eocene sediments (sandstones, shales, and siltstones) with ultrabasic igneous intrusions predominate.
- As to the speed of cutting, in the experiment quoted a bit of rather friable "gabbro," measuring three-quarters of an inch on the face by five-eighths of an inch thick, was cut clean through in six minutes, or by 3000 turns of the wheel.