Igneous rocks are the "new kids" in the rock cycle. They're the new rock on the block, ready to start fresh. Basalt lava flow in Hawaii, a perfect example of an extrusive igneous rock.

University of Hawaii ‑ SOEST. "Extrusive volcanism formed the Hawaiian Islands." ScienceDaily. ScienceDaily, 7 October 2013. <www.sciencedaily.com / releases / 2013 / 10 / 131007094558.htm>.

Previous estimates of the internal-to-extrusive ratios (internally emplaced magma versus extrusive lava flow) were based on observations over a very short time frame, in the geologic sense.

Extrusive rocks cooled quicker, thus they formed very small mineral crystals and, in most cases, you can see only a speckle from the minerals.

Lunar igneous activities including intrusive and extrusive magmatism, and their products contain significant information about the lunar interior and its thermal state. Their distribution is ...

Current issues are now on the Chicago Journals website. Read the latest issue.One of the oldest journals in geology, The Journal of Geology (JG) has since 1893 promoted the systematic philosophical ...

The first magma flowed through the sill and broke out near the northern end as three Orange Mountain basalt flows. Each of the three extrusive pulses is identified within the lower 150 m of the sill ...