Quiz: Understanding Igneous Rocks - Formation, Types, and Characteristics

Intrusive Igneous Rock forms when magma cools slowly beneath the earth's surface, allowing crystals to grow to large sizes. Extrusive Igneous Rock, Metamorphic Rock, and Sedimentary Rock form through different processes and do not involve slow cooling beneath the surface.

Pumice is a light-colored vesicular igneous rock known for its rapid solidification process and distinctive vesicular texture. Obsidian is a dark-colored volcanic glass that forms without any crystalline structure. Basalt is a dark-colored fine-grained igneous rock commonly found in oceanic crust. Rhyolite is a light-colored fine-grained igneous rock with high silica content.

Scoria is a type of volcanic rock with vesicles. Obsidian is a dark volcanic glass without vesicles. Basalt is a dark extrusive igneous rock without vesicles formed by trapped gas. Pumice is a light-colored vesicular igneous rock.

Basalt is a fine-grained igneous rock that is typically dark in color, whereas Granite is coarse-grained, Obsidian is a natural glass formed from molten lava, and Gabbro is a coarse-grained equivalent of basalt.

Obsidian is a type of naturally occurring glass that is formed when felsic lava cools rapidly, resulting in a dark-colored, glossy stone with conchoidal fracture patterns. Unlike obsidian, quartz, marble, and slate are not types of naturally occurring glass formed from lava cooling rapidly.

Andesite is a volcanic rock commonly found in volcanic arcs. Basalt is another common extrusive igneous rock, but it typically has a lower silica content compared to andesite. Granite is a coarse-grained intrusive igneous rock, and rhyolite is another fine-grained extrusive rock but with a higher silica content than andesite.

Peridotite is the correct answer as it is specifically described as a coarse-grained intrusive rock composed mainly of olivine, with possible presence of other minerals. Basalt is an extrusive igneous rock. Gabbro is also intrusive but consists mainly of calcium-rich plagioclase feldspar and pyroxene. Granite is a coarse-grained intrusive rock primarily composed of feldspar, quartz, and mica.

Diorite is distinct from granite due to its higher content of dark minerals, while basalt and gabbro have different mineral compositions.

Gabbro is a dark-colored coarse-grained intrusive igneous rock, while Basalt, Granite, and Obsidian are different types of rocks with varying characteristics.

Rhyolite is a light-colored, fine-grained, extrusive igneous rock that typically contains quartz and feldspar minerals, making it different from basalt, granite, and obsidian.