Is porphyritic rock extrusive or intrusive? - Answers
Jun 16, 2024 · Porphyritic rock can be either extrusive or intrusive. If the larger crystals formed deep within the Earth's crust before being forced to the surface, it is intrusive. If the larger crystals ...
What is a porphyritic texture? - Answers
May 22, 2024 · A porphyritic texture is a type of rock texture characterized by having large, well-formed crystals (phenocrysts) embedded in a fine-grained matrix (groundmass). This indicates that the rock ...
What is an igneous rock with both large and small crystals?
Jun 12, 2024 · A rock with both large and small crystals is called a porphyritic igneous rock. This type of rock forms when molten rock cools slowly underground, allowing larger crystals to form first ...
Which igneous rock cools the fastest glassy aphanitc pegmatic and ...
Jun 12, 2024 · A rock with both large and small crystals is called a porphyritic igneous rock. This type of rock forms when molten rock cools slowly underground, allowing larger crystals to form first ...
Is pumice a metamorphic rock? - Answers
Jun 8, 2024 · No pumice is not a porphyritic igneous rock, a porphyritic rock is characterized by the presence of phenocrysts (large mineral grains) and very small mineral grains with none in between. This ...
What is a rock with long flat mineral grains? - Answers
Jun 17, 2024 · Phenocrysts are the larger mineral grains in a porphyritic igneous rock. These crystals are surrounded by a finer-grained matrix known as the groundmass. The presence of phenocrysts helps in ...
What kind of texture does a rock with large crystals ... - Answers
Jun 10, 2024 · The rock would have a porphyritic texture, with large crystals (phenocrysts) embedded in a finer-grained matrix (groundmass). This texture is typically the result of two stages of cooling during ...
How do porphyritic rocks form? - Answers
Jun 16, 2024 · A porophyritic rock is igneous by classification. Porphyritic rocks begin to form below the surface when minerals with a higher melting temperature crystallize and are carried to or near the ...
What affects the grain size of igneous rock? - Answers
Jun 18, 2024 · Porphyritic texture indicates that a magma has gone through a two stage cooling process. The magma has cooled sufficiently underground to allow some minerals to crystallize and grow in size; the ...
What is the size of a crystal in an extrusive igneous rock?
Jun 13, 2024 · The exception would be a porphyritic rock that has visible crystals dispersed in a fine-grained matrix. This type of rock represents a partial cooling of magma before expulsion by volcanism. Wiki User