Try our free app!
Our expert volcanologists and photographers offer unique travel experiences: volcano expeditions
, photo tours, and relaxed walking & study tours.
: spaces available / : guaranteed / : few spaces left / : booked out
Diorite sample (image: Michael C. Rygel via Wikimedia Commons)
Diorite is an intrusive igneous rock of intermediate silica content (53-63%). It is the equivalent of its extrusive (volcanic) counterpart andesite.
Diorite is composed principally of the silicate minerals plagioclase feldspar (typically andesine), biotite, hornblende, and/or pyroxene. The chemical composition of diorite is intermediate between gabbro and granite.
More on VolcanoDiscovery
Eruption from close
: On 17 Oct, explosions were particularly violent at Anak Krakatau. We show a series of images of a spectacular explosion captured from close range by boat.
Small spherical balls of volcanic ash that form from a wet nucleus falling through a volcanic ash cloud.
Largest 20 earthquakes past 24 hrs
: Our continuously updated worldwide map and list of the most recent largest earthquakes in the world during the past 24 hours.
You can also find top 20 lists for given past days / months / years from the archive.