2016-10-24T11:04:12ZThe Appalachian Mountains contain a very complex (and lengthy) geologic history. Learn more about what makes them so special.
2016-10-24T11:04:12ZThe zirconium minerals zircon, baddeleyite and zirconolite are a close family.
2016-10-24T11:04:12ZFeldspar is a major rock-forming mineral. Page 5.
2016-10-24T11:04:12ZSalt is the only dietary mineral that's really a mineral. It comes from the sea and from solid layers underground.
2016-10-24T11:04:12ZGeologists have named a variety of holes.
2016-10-24T11:04:12ZPyroxene is a rock-forming mineral. Page 8.
2016-10-24T11:04:12ZHow we track Earth's magnetism back in geologic time, and what that tells us.
2016-10-24T11:04:12ZStart here to learn the basics of plate tectonics.
2016-10-24T11:04:12ZTernary diagram showing IUGS classification of volcanic rocks. Page 2.
2016-10-24T11:04:12ZAn assortment of conglomerates.
2016-10-24T11:04:12ZThe five ways we track the motion of the lithospheric plates.
2016-10-24T11:04:12ZEpidote is one of the silicate minerals. Page 10.
2016-10-24T11:04:12ZGeologic map of Nevada, part of a set of all 50 states. Page 28.
2016-10-24T11:04:12ZQuick identification table for the minerals that form the majority of rocks.
2016-10-24T11:04:12ZThirty-five states have official gems or gemstones, while Montana and Nevada have two. Here they all are, along with the date that they were adopted.
2016-10-24T11:04:12ZGlaucophane in the gallery of amphibole minerals. Page 9.
2016-10-24T11:04:12ZGeologic map of South Dakota, part of a set of all 50 states. Page 41.
2016-10-24T11:04:12ZGet familiar with quartz.
2016-10-24T11:04:12ZCalcite is a rock-forming mineral, most important in limestone. Page 3.
2016-10-24T11:04:12ZThe whole Earth on average consists of the same mixture of stuff we see elsewhere in the solar system, but the core has to be iron metal along with some nickel.
2016-10-24T11:04:12ZCoal, a fossil fuel, is formed when plant matter becomes buried and compacted in an anoxic environment.
2016-10-24T11:04:12ZThis mineral resource has been first a boon, then a bane in its century of commercial existence. Learn more about the minerals themselves.
2016-10-24T11:04:12ZFlute casts are widespread signs of geologic history in sedimentary rocks. Page 8.
2016-10-24T11:04:12ZGeologic map of Iowa, part of a set of all 50 states. Page 15.
2016-10-24T11:04:12ZActinolite in the gallery of amphibole minerals. Page 6.
2016-10-24T11:04:12ZIn rocks, what is not there can be as informative as what is there.
2016-10-24T11:04:12ZThe special form of soil flow typical of glaciated regions.
2016-10-24T11:04:12ZStart here for the seismic basics: faults that cause earthquakes, types of seismic waves, damages they cause and more.
2016-10-24T11:04:12ZHome page for everything about the San Andreas fault: where it is, how it behaves, what it means.