vadose zone — ▪ hydrology region of aeration above the water table. This zone also includes the capillary fringe above the water table, the height of which will vary according to the grain size of the sediments. In coarse grained mediums the fringe may… … Universalium
semiconformable alteration zone — GLOSSARY OF VOLCANIC TERMS A regional zone of hydrothermal alteration typically characterized by a sheet like or cloud like geometry. Semiconformable alteration zones are generally quite extensive in permeable rock units (e.g. tuffs, medium to… … Glossary of volcanic terms
river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… … Universalium
Geology of the Australian Capital Territory — Australia grew around three fused pieces of very ancient continental crust (cratons). The geology of the Australian Capital Territory includes rocks dating from the Ordovician around 480 million years ago, whilst most rocks are from the Silurian … Wikipedia
igneous rock — Any of various crystalline or glassy, noncrystalline rocks formed by the cooling and solidification of molten earth material (magma). Igneous rocks comprise one of the three principal classes of rocks, the others being metamorphic and sedimentary … Universalium
Cornubian batholith — Map showing the main granite outcrops of the Cornubian batholith in southwest England and the location of Haig Fras the 20 mGal Bouguer anomaly is also shown as this indicates the location of the negative anomalies associated with these… … Wikipedia
Ordovician Period — Interval of geologic time, 490–443 million years ago, the second oldest period of the Paleozoic Era. It follows the Cambrian and precedes the Silurian. During the Ordovician, many of the landmasses were aligned in the tropics. Life was dominated… … Universalium
Africa — /af ri keuh/, n. 1. a continent S of Europe and between the Atlantic and Indian oceans. 551,000,000; ab. 11,700,000 sq. mi. (30,303,000 sq. km). adj. 2. African. * * * I Second largest continent on Earth. It is bounded by the Mediterranean Sea,… … Universalium
Igneous rock — Geologic provinces of the world (USGS) Shield … Wikipedia
Marine geology of the Cape Peninsula and False Bay — Contents 1 Introduction 2 The geological structure of the region 2.1 Malmesbury group deposition 2.1.1 Appearance of the exposed Malmesbury group rocks … Wikipedia
Gabbro — (pronEng|ˈɡæbrəʊ) is a dark, coarse grained, intrusive igneous rock chemically equivalent to basalt. It is a plutonic rock, formed when molten magma is trapped beneath the Earth s surface and cools into a crystalline mass. The vast majority of… … Wikipedia
