安裝中文字典英文字典辭典工具!
安裝中文字典英文字典辭典工具!
|
- Porphyry (geology) - Wikipedia
Porphyry ( ˈ p ɔːr f ə r i POR-fə-ree) is any of various granites or igneous rocks with coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass
- What Is Porphyry? How Does It Form, and In Which Rocks?
Porphyry (pronounced as POR-fə-ree) describes any intrusive or extrusive igneous texture rock with large-grained crystals embedded in a finer-grain matrix The finer-grained groundmass or matrix can be aphanitic or phaneritic However, the larger crystals must be easily noticed and distinguishable
- Porphyry (geology) - New World Encyclopedia
Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass The larger crystals are called phenocrysts
- Porphyry Deposits - Geology Science
Porphyry deposits are a type of mineral deposit that form from large-scale hydrothermal systems associated with intrusive igneous rocks They are characterized by the presence of porphyritic rocks that contain large crystals (phenocrysts) surrounded by a fine-grained matrix (groundmass)
- Porphyry - Igneous Rocks - Sandatlas
Porphyry is an igneous rock characterized by porphyritic texture Porphyritic texture is a very common texture in igneous rocks in which larger crystals (phenocrysts) are embedded in a fine-grained groundmass
- PORPHYRY Definition Meaning - Merriam-Webster
The meaning of PORPHYRY is a rock consisting of feldspar crystals embedded in a compact dark red or purple groundmass
- Porphyry | geological feature | Britannica
(A porphyry is an igneous rock containing conspicuous crystals, called phenocrysts, surrounded by a matrix of finer-grained minerals or glass or both ) In most rocks, both alkali and plagioclase feldspars occur as irregularly shaped grains with only a few or no crystal faces
- Porphyry: Mineral information, data and localities. - mindat. org
The rock name descriptive of the groundmass composition usually precedes the term; e g , diorite porphyry In many cases the main phenocryst minerals precedes the name, e g quartz porphyry or quartz-feldspar porphyry Porphyrite is a mostly obsolete variety with dominant plagioclase phenocrysts
|
|
|