GLOSSARY OF TERMS

Geology: The study of the planet Earth, the materials of which it is made, the processes that act on these materials, the products formed, the history of the planet and its life forms since its origin.

Geologist: One who is trained and works in any of the geological sciences.

Formation: A body of rock identified by lithological (rock type) characteristics and stratigraphical (age) position. Formations may be combined into groups or subdivided into members.

Ophiolite: A group of igneous rocks whose origin is associated with seafloor spreading (production of oceanic crust).

Autochthonous: Formed or produced in the place where now found.

Alpine Orogenic Zone: A name for the relatively young mountain-forming events of southern Europe and Asia, by which the rocks of Alps were strongly deformed.

Orogeny: The process of the formation of mountains.

Allochthonous: Formed or produced elsewhere than in its present place (of foreign origin or introduced).

Ma: Millions of years before the present.

Tethys: An ocean that occupied the general position of the Alpine-Himalayan orogenic belt; the Mediterranean Sea is a remnant of Tethys.

Plutonic (rocks): This is a group of igneous rocks formed at a greater depth in the Earth.

Pillow lavas: A general term for those lavas (volcanic rocks) displaying pillow structure and considered to have formed in a subaqueous (marine) environment.

Chemical rock: A sedimentary rock composed primarily of material formed directly by precipitation from solution.

Diapiric:  A structural shape of a rock on Earth that looks either circular or elliptical in outline. This feature originates from the lateral forces of the tectonic movements. 

Igneous: Rocks or minerals that solidified from molten or partly molten material, i.e. from magma.

Sedimentary: Rocks that formed by deposition and consolidation of sediment.

Metamorphic: Any rock derived from pre-existing rocks by mineralogical, chemical and/or structural changes, essentially in the solid state, in response to marked changes in temperature, pressure and chemical environment, generally at depth in the Earth’s crust.

Volcaniclastics: This is a term used for the igneous rocks which bear angular volcanic fragments. 

Mélange: A body of rock characterised by the inclusion of fragments and blocks of all sizes embedded in a fragmental matrix of finer-grained material.

Pelagic: This is a term used for the water of the ocean which is an environment for sediment accumulation.

Chert: A hard and extremely dense sedimentary rock that predominantly consists of very fine quartz crystals.

Reef limestone: A limestone consisting of the remains of active reef-building organisms, such as corals, sponges and of sediment-binding organic constituents, such as calcareous algae.

Evaporite: A sedimentary rock composed primarily of minerals produced from a saline solution as a result of extensive or total evaporation of the solvent (i.e. gypsum).

Calcarenite: A limestone predominantly consisting of recycled (redeposited) calcite particles of sand size. 

Clastic: Pertaining to a rock or sediment composed principally of broken fragments that are derived from pre-existing rocks or minerals and that have been transported some distance from their places of origin.

Subduction: The process of one lithospheric plate descending beneath another.

Sedimentary basin: A low, depressed area in the Earth’s crust, of tectonic origin, in which sediments have accumulated.