That depends on the rock and the type of metamorphism is underwent. Some rocks become more dense, some become less.
Than?? Marble certainly isn't porous.
Dense. Light colored igneous rocks have lower density compared to dark colored igneous rocks due to their higher silica content, which results in slower cooling and the formation of larger crystals.
Rocks become less dense when they melt
Low-grade metamorphism is a process where rocks are subjected to relatively low temperatures and pressures compared to higher-grade metamorphism. It results in the alteration of mineralogy and texture of rocks without completely melting them. This process typically occurs in the temperature range of 200-450°C and at low to moderate pressures.
No, rocks are denser than mercury, so they would sink in mercury. Mercury is a very dense liquid at room temperature, so objects that are less dense than mercury will float on it.
Rocks that undergo metamorphism can become either more or less dense, depending on the specific changes that occur. For example, the recrystallization of minerals during metamorphism can often lead to an increase in density, while the introduction of new minerals or pore spaces can result in a decrease in density.
Than?? Marble certainly isn't porous.
Because contact metamorphism usually occurs because of an increase in temperature. In contrary, regional metamorphism is usually the result of compression. Compression makes a rock more dense.
Crustal rock is normally less dense than mantle rock.
Contact metamorphism does not cause profound compaction, which is the reduction in size of the spaces between mineral particles due to increases in pressure. Regional metamorphism causes compaction and possibly recrystallization, increasing the density of the rock.
less dense
Because in contact the rock actually comes in contact with magma, this joins with the rock, so when it cools and become igneous rock, it's denser. In regular, or regional, the rock is formed from intense heat and pressure, but does not actually come in contact with magma.
less dense rocks such as granite.
Contact metamorphism occurs when rocks are subjected to high temperatures and pressures due to being in close proximity to an igneous intrusion, leading to localized changes in mineralogy and texture. In contrast, regional metamorphism affects large areas of rocks over a wide region due to tectonic forces such as mountain building or subduction, resulting in widespread changes in mineralogy and texture. Contact metamorphism is therefore more localized and less intense compared to regional metamorphism.
All rocks are changed, but it depends on the density. A smooth, hard volcanic rock may take a while to weather because it has less friction, but a bumpy less dense rock may weather faster. However, all rocks wear down by means such as human touching, water, wind, or friction with other rocks. For example in tourist caves some rocks have become smooth from the human touch repeated over and over.
Dense. Light colored igneous rocks have lower density compared to dark colored igneous rocks due to their higher silica content, which results in slower cooling and the formation of larger crystals.
Rocks become less dense when they melt