Tenerife is an island created volcanically, building up from the ocean floor 20-50 million years ago.
Underwater eruptions originated from the pillow lava, which are produced by the rapid cooling of the magma when it comes in contact with water, obtaining their peculiar shape. This pillow-lava accumulated, constructing the base of the island underneath the sea. As this accumulation approached the surface of the water, gases erupted from the magma due to the reduction of the surrounding pressure. The volcanic eruptions became more violent and had a more explosive character, and resulted in the forming of peculiar geological fragments.
After long-term accumulation of these fragments, the birth of the island occurred at the end of the Miocene Epoch. The zones on Tenerife known as Macizo de Teno, Macizo de Anaga and Macizo de Adeje were formed 7,000,000 years ago; these formations are called the Ancient Basaltic Series or Series I. These zones were actually three separate islands lying in what is now the extreme west, east, and south of Tenerife.
A second volcanic cycle began 3,000,000 years ago called the Post-Miocene Formations or Latest Series II, III, IV. This was a much more intense volcanic cycle, which united the Macizo de Teno, Macizo de Anaga and Macizo de Adeje into one island. This new structure, called the Pre-Cañadas Structure (Edificio pre-Cañadas), would be the foundation for what is called the Cañadas Structure I. The Cañadas Structure I experienced various collapses.
The Anaga massif (Macizo de Anaga), at the northeastern end of the island, has an irregular and rugged topographical profile where, despite its generally modest elevations, the Cruz de Taborno reaches a height of 1,024 metres.
The Adeje massif (Macizo de Adeje) is situated on the southern tip of the island. This massif is not as impressive as the others.
The Teno massif - Cliffs of the Giants area
The Teno massif (Macizo de Teno) is located on the northwestern edge of the island. Like Anaga, it includes an area of outcroppings and deep gorges formed by erosion. However, the materials here are older (about 7.4 million years old). The most unusual landscape of this massif is found on its southern coast, where the Acantilados de Los Gigantes ("Cliffs of the Giants") present vertical walls of igneous rocks.
A rock structure can be created in any rock type or combination:
1. Sedimentary rocks are created from bits of rocks that have broken off other rocks by wind or water erosion, and deposited by wind, ice, or water. Erosion later exposes them in their current form.
2. Metamorphic rocks are created by rocks that have evolved into another kind of rock, usually by heat and pressure.
3. Igneous rocks are created when molten rock cools and solidifies, with or without crystallization. They may be either plutonicbodies or volcanic extrusives. Again, erosive forces sculpt their current forms.
Geologists have created a number of terms to describe different rock structures in the landscape that can be formed by natural processes:
- Inselberg is a residual relief feature. It can be an isolated hill, a knob, ridge or small mountain that rises abruptly, like an island, from a gently sloping or virtually level surrounding plain. Inselberg is a German word that means "island mountain".
- Sea cliff
- River cliff
- Stone run
Los Gigantes is a typical repesentative of a sea cliff rock formation.
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a) Please estimate the hight of the Los Gigantes cliff on its highest points?
b) What is the name of the Teno massif point that goes furthest into the ocean ? ( the infoboard will help)
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