Geological History


Alluvial fan

Accumulation of sediments deposited in the shape of a cone, at the foothill of mountain ranges.


Magmatic activity

Process related to magma. Magma is the paste-like liquid material found under the earth’s inner crust at high temperatures and pressure.  Magma’s solidification originates the formation of igneous rocks.



They are bodies formed by the accumulation de sediments, developing in coastal areas, where rivers flow into the oceans, seas or lakes, in conditions where the contribution of sediments is quicker than the process of redistribution of sediment to the receiving basin.



Unicellular organism mainly marine; its size can vary from 1 mm to some visible to the naked eye.  They have a calcareous skeleton composed of variable shaped chambers.



Body of rocks strata with certain characteristics of homogeneity, recognizable in surface as well as depth; it may be represented in a map and differentiable as to higher and lower strata.  Is named and analyzed with the purpose of grouping and ordering the spatial and temporal distribution of the diverse types of rocks and sediments.



Dark grey to black color igneous plutonic or intrusive rock; texture is phaneritic or granular, meaning minerals may be observed with the naked eye.  Basic composition (high calcium contents), essentially composed of calcium-sodium feldspars (plagioclases, scarce orthoclase) and the minerals iron and magnesium, with no quartz.



Igneous plutonic or intrusive rock, with high silica contents; its essential minerals are quartz and feldspars with orthoclase predominant over plagioclases, with no olivine. Texture is phaneritic or granular, meaning minerals may be observed with the naked eye.  Granite is light-colored (white, greyish) when quartz content is greater; when it has a high proportion of potassium feldspars, granite becomes slightly pink.


Intrusive rock

Igneous rocks formed in the earth’s inner crust, from cooling of magma.  Magma penetrates and cools off between the gaps of pre-existing rocks.