GlossaryPrint

Sandstone

sedimentary rock, also known as arenite, consisting of sand-sized rock grain or minerals (quartz dominant) or rock fragments, aggregated by a cement which may be siliceous, carbonate or ferruginous. Sandstone may or may not present stratification, that informs about its environment and process of sedimentation.

 

Schist

metamorphic rock of varied composition that is mainly characterised by its schistosity, which enables it to break up very easily along parallel planes.

Scraper or end-scraper

stone instrument produced on the extremity of a flake or blade, characterised by a cutting work edge with a rounded morphology obtained by retouch. Thick end-scrapers were also used to produce bladelets.

 

Scraping tool

stone instrument produced from a flake with continuous retouch along one or more edges.

Sedimentary rock

rock formed at the surface of the planet, on land or in the sea floors, by accumulation of sediments and their subsequent consolidation (diagenesis). It occupies over 75% of the land area.

 

Seismic activity

result of the internal dynamics of the Earth, manifested in movements that may be sudden or slow, in response to fault motion, volcanic activity or to the collision between tectonic plates, with release of large amounts of energy in the form of seismic waves (superficial or deep).

Shaping

method that aims to produce a single stone instrument, shaping the raw material in accordance with a form envisioned beforehand. This procedure entails the successive removal of the initial volume of raw material (a block or flake) on one face (single face shaping) or two opposite faces (bifacial shaping).

 

Siberia

continent formed at the beginning of the Paleozoic by the areas of solid land that today comprise Siberia.

Silurian (444-416 Ma)

period of the Paleozoic Era marked by the appearance of the first fish, plants and land animals. During this period, the expansion of the Iapetus Ocean began to stop. Later, the Iapetus will close due to the collision of Paleolaurentia with Baltica. From this collision resulted the Caledonian cordillera. Traces of this cordillera still exist in northern Europe, Greenland and North America.

Site of Biological Interest

protected area not administered by the State but by private owners. These areas seek the protection of flora and wildlife species, with manifest interest to science and to maintain the ecological balance, and respective habitats.

Smilodon

extinct mammal that lived from the Pliocene (5-2.5 Ma) to about 12 000 years ago. It was a descendant of the first feline carnivorous sabre-tooth tigers, more robust than present-day lions, and had canine teeth that could measure up to 20 cm in length. Several fossils of this animal were found in the American continent.

Solutrean

technology-complex of the European Upper Palaeolithic, geographically represented in France (South of the Loire Valley and limited on the east by the Rhone Valley), and in all of Spain and Portugal, defined by the development of lithic points, covering the period from 22,000 to 17,000 years before the present.

 

Special Protection Zone (SPZ)

within the framework of the Birds Directive of the Natura 2000 Network, these areas aim to promote the conservation and protection of birds and their habitats, ensuring their survival and reproduction.

Stone industry

assemblage of produced stone objects, recurrent in time and space, and resulting from prehistoric man’s action and technical activities on stone raw-materials.

 

Stratification

characteristic arrangement in layers or superimposed beds of sedimentary rocks. The inclinations are the result of changes in velocity of deposition, direction of river, marine or wind currents that carried the elements that constitute the rock. Original sedimentary structure can also gain different tilting from the original arrangement by tectonic activity.

 

Stromatolite

rock formed by small particles agglutinated by carbonate cement segregated by blue algae (cyanobacteria) and/or bacteria. Stromatolites are typical of warm and shallow seas and exist since the Precambrian (~ 4 600 Ma).

Sub-aerial erosive processes

transformation processes inherent to the removal of matter from one place to another (erosion), with the intervention of several agents, such as water, wind or human activities.

 

Subduction or Benioff zone

area of the Earth where two tectonic plates collide with one another (convergence zone), in which one moves on the other towards the earth mantle. Usually an oceanic plate moves under a continental plate or under another oceanic plate. These are regions usually correspond to areas of mountain formation or volcanic areas, and where seismic activity is present.

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