Geology

May 12, 2011  

Although modern geology appeared in the eighteenth century, the Earth was already studied by the Greco-Roman philosophers. The Greek philosopher Theophrastus (371 to 287 BC) described and classified minerals according to their physical properties. The Roman writer Pliny the Elder (23-79 AD) described minerals, crystals and fossils. Also some medieval Muslim scholars proceeded in the field of geology. Al-Biruni (973 – 1048) described the geology of the Indian subcontinent and believed this area was once a sea. Avicenna (981 – 1037) described the formation of mountains as an interplay between tectonic forces and erosion . He believed that mountains had made this form which aproved that the Earth is very old. The Chinese scholar Shen Kuo (1031-1095) independently came to similar ideas.
In Europe one of the first naturalists was Leonardo da Vinci (1452-1519). Da Vinci understood that the fossil shells that he found in the Apennines are indeed remnants of life from earlier times. The Venetian physician Georgius Agricola (1494-1555) was particularly interested in the mining industry. He shared the first rocks in a methodical way: in four groups of consecutive age and consolidation. Nicolaus Steno (1638 – 1686) investigated how rock layers are formed and proposed three laws, with which he was the founder of the stratigraphy.

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View Ancient History in the Geology of Cape Town

October 12, 2011  

Over Six Hundred Million years ago the rocks in Cape Town were just beginning to form. Over the next hundred million years they went through tremendous trauma and reformation. It is fascinating that we can see into the past by looking at these geological features that are still around today! You can get in your car and go on a beautiful and informative drive through Chapmanâ??s Peak that will take you between layers of Granite and Sandstone. You can hike through craggy mountains and actually sit on the ancient stone that was in place long before your own ancestors.

Geology has become a hot topic, and with good reason. Geology is literally the foundation upon which we stand, and one of the first exciting science subjects. In Cape Town you will find multiple examples of geologic wonders where you can literally see the history of how earth was formed through looking at these awesome and accessible geological examples in the area.

You can choose between Table Mountain, Sea point Promenade, or the numerous other geologically important sites around Cape Town. Or you can even see them all and you will find your self in the same foot prints as Charles Darwin, staring in awe at the ancient history of earth laid out before you in tremendous rock formations.

Along with the interesting geology the rocks offer, you can see how the rocks themselves effect the soil. In the mountains you will find a variety of unique plant classifications. If you drive through the agricultural region you will discover a wheat industry that thrives in the fine grained soils surrounding this mountainous, rocky region.

Cape Town is an area rich in Geological history, that you can see and feel for yourself, in each rocky crag, each compressed formation, and hardened lava flow.

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What Causes a Tsunami?

October 07, 2011  

A huge ocean wave known as a tsunami occurs when there is an unexpected movement on the ground of the ocean. The tsunami sweeps across the ocean at a very fast speed, which results in massive waves hitting the shoreline with a deadly force. The movement can be causeb by an earthquake, volcano eruption or a landslide that happens on the ocean floor; even a meteorite slamming into the ground could be responsible for triggering a tsunami.

The majority of tsunamis are created when an earthquake occurs in a subduction area of the bottom of the ocean. This causes the oceanic plate below the ocean to be pushed down against the mantle by the force of plate tectonics. This produces a vast friction amid the subducting plate and the overriding plate causing the two plates to slowly lodge together. The consequence of this occurrence is a collection of energy over a long extended amount of time that becomes similar to spring loaded energy.

A tsunami is then triggered when a sudden force of motion is caused when the energy gathers in the overriding plate and then surpasses the frictional strength sandwiched amid both of the stuck plates. This causes the overriding plate to spontaneously release back into an uncontrolled position, which pushes out strong waves from the impact of the earthquake. The waves travel at a rapid pace until they spillover on the shoreline with a deadly force. Contrasting to what many individuals visualize as one enormous destructive wave, a tsunami produces numerous forceful, devastating train-like waves.

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Sturt’s Stony Desert

May 12, 2011  

Sturt’s Stony Desert is placed in South Australia. It is covered with a layer of siliceous and glazed stones. The surface of gibber deserts appears hard, but the surface beneath the gibbers is actually soft, and readily turns to mud after rain.

Under these stones there is a conchodial fracture stones. The Aboriginal people used these stones as pre-formed blades for tool making. According to its discoverer Sturt’s account from 1840, there were on every side ‘stupendous and almost unsurmountable sand ridges of a fiery red’. Most of the sand has now been moved from the area, and have been accumulating in depressions between the plateaux that are strewn with gibbers or carried further downwind to lowlands. Burke & Wills wrote of their 1861-62 expedition, between the dunes and near residual rises and uplands, especially those with a silcrete capping, the ground is covered ‘with sharp dark brown stones that were terrible to walk on’.

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