Across
- 3. (pronounced "nice") - a banded or striped rock with alternating layers of dark and light minerals
- 4. is magma extruded on or very near the Earth’s surface. Most lavas have been significantly degassed en route to the surface.
- 8. texture rocks with mineral grains that are large enough to be identified by eye. Texture is typical of slowly cooled intrusive rocks.
- 10. or volcanic rocks: typically aphanitic or glassy. This means that they are generally fine grained in texture. Grains are typically 0.5 to 1 mm. Common example is basalt.
- 11. metamorphic rock containing abundant obvious micas, several millimeters across
- 12. fizzes in acid because its dominant minerals is calcite (or dolomite). The parent rock is limestone.
- 14. or plutonic rocks: typically phaneritic. This means that they are generally coarse grained and this texture is often quite uniform. Grains can range in size but are often clearly visible to the naked eye (>2-3 mm). Common example is granite.varieties are porphyritic. This means that the grain size is bimodal, with a fine grained matrix surrounding larger grains that are called phenocrysts. Common example is andesite
- 15. rocks mnemonic based on feldspar and silica. Also applies to rocks containing abundant feldspathoids, such as nepheline. GRANITE
- 16. is molten rock (fluid) typically deep below the surface, rich in silica (SiO2), which contains dissolved volatiles (e.g. CO2 and H2O).
- 17. A dynamic metamorphic rock which forms along fault zones
- 18. interlocking grains of quartz. Scratches glass. The rock fractures through the grains (rather than between the grains as it does in sandstone). The parent rock is quartz sandstone.
- 20. composed mostly of rounded, waterworn, cemented-together pebbles much larger than sandgrains; the pebbles are usually of quartz
- 23. rocks very rich in Mg and Fe. Generally have little feldspar. PERIDOTITE
- 24. rocks are formed as a result of cooling and crystallization from a magma.
Down
- 1. basically sand grains cemented together, which may have been deposited as sand dunes, sand bars, or washed into the sea; that's a genuine sandstone rock at the right
- 2. fine-grained metamorphic rock. Has a frosted sheen, resembling frosted eye shadow
- 4. composed of calcium carbonate (calcite), which may have been chemically precipitated in the sea, or else deposited by living organisms in the sea; often contains fossils of sea life
- 5. very fine grained rock. Resembles shale. Has slaty cleavage which may be at an angle to the original bedding
- 6. rocks mnemonic based on magnesium and ferrous/ferric. Synonymous with ferromagnesian, which refers to biotite, amphibole, pyroxene, olivine, and Fe-Ti oxides. BASALT
- 7. texture rocks with grain too small to be identified by eye. Texture is most common in rapidly solidified extruded magma and marginal facies of shallow intrusions.
- 9. that it has partially melted
- 11. rocks dominated by quartz and alkali fsp. Sometimes referred to as sialic (Si + Al).
- 13. a very high grade metamorphic rock that has been subjected to such high
- 19. texture magmatic rocks with bimodal grain size distributions
- 21. like limestone, except that it has more magnesium in it
- 22. or vitric texture rocks that contain variable proportions of glass
- 25. composed mostly of tiny clay particles of the kind found in mud, much smaller than sand particles, so shale is smoother than sandstone
