• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

James Hutton (1727-1797), the eminent 18th century gentleman farmer and founder of modern geoscience, authored the concept of the rock cycle, which depicts the interrelationships between igneous, sedimentary, and metamorphic rocks.

Extracts from this document...

Introduction

James Hutton (1727-1797), the eminent 18th century gentleman farmer and founder of modern geoscience, authored the concept of the rock cycle, which depicts the interrelationships between igneous, sedimentary, and metamorphic rocks. The upper part of the earth (mantle, crust and surface) can be envisioned as a giant recycling machine; matter that makes up rocks is neither created nor destroyed, but is redistributed and transformed from one rock type to another. PETROLOGY, the study of rocks and their origins, is essentially the formal process by which we resolve the interrelationships expressed in the rock cycle. Liquid (molten) rock material solidifies at depth or at the earth's surface to form IGNEOUS ROCKS . Uplift and exposure of rocks at the Earth's surface destabilizes these mineral structures (c.f. Bowen's Reaction Series). The minerals break down into smaller grains which are transported and deposited (either from solution or by lowering the hydraulic energy regime) as sediments. The sediments are lithified (compacted and cemented), and SEDIMENTARY ROCKS are formed. Changes in temperature, pressure, and/or rock or fluid chemistry can allow igneous and sedimentary rocks to change physically or chemically to form METAMORPHIC ROCKS. ...read more.

Middle

Igneous rocks form by direct crystallization of minerals from a magma melt; we see a surface expression of magmatic activity at sea-floor spreading ridges and other rift zones, volcanic arcs (subduction zones) and hot spots (intraplate volcanism).. Intrusive (plutonic) rocks crystallize at depth, whereas extrusive (volcanic and pyroclastic rocks) rocks crystallize after the magma reaches the earth's surface. In general, extrusive rocks have a finer grained texture than intrusive rocks. Igneous rocks are often classified according to the percentage of SiO2. The figure below is a general guide to igneous rock classification, showing the rock names and the differences in mineralogy. Sedimentary rocks form from pre-existing rock particles - igneous, metamorphic or sedimentary. The Parent rock undergoes WEATHERING by chemical and/or physical mechanisms into smaller particles. These particles are TRANSPORTED by ice, air or water to a region of lower energy called a sedimentary basin. DEPOSITION takes place as a result of a lowering of hydraulic energy, organic biochemical activity or chemical changes (e.g., solubility). Once deposited, the sediments are LITHIFIED (turned into rock) ...read more.

Conclusion

Think of exfoliation as flaking. Freeze-thaw weathering occurs when water gets into cracks in rock and then freezes (below 0 �C) in cold weather. Water expands when it freezes and turns to ice, and the expansion can cause the rock to split and fragment. In warmer weather (above 0 �C) the ice melts (called thawing), and new cracks are exposed allowing the process to repeat itself. Erosion is a slow process of wearing away weathered rock by action of the wind, rivers and waves. Metamorphic rocks Both slate and schist (pronounced "shist") are formed from the sedimentary rocks mudstone and shale. Mudstone and shale are formed from compacted mud or clay. They are made of very small flat particles like tiny plates, which have often become layered during the sedimentary rock formation. Metamorphic Rocks - Marble. Marble is formed from limestone. At high temperatures and pressures, the shells which formed limestone break down and recrystallize. The resultant rock is marble, which is much harder than limestone, with a smooth even texture. Marble is a valuable rock for construction and decoration. It can be polished to produce an attractive mottled surface. Marble is still calcium carbonate, and reacts chemically in the same way as limestone. Granite pics - Bsalt - ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Rocks & Weathering section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Rocks & Weathering essays

  1. The Economic Value of Igneous Activity.

    The stone is also very cheap to purchase as there is no demand to the actual presence of the material and it is being made all the time.

  2. Sedimentary Rocks

    Most of our coal was formed about 300 million years ago when the earth was covered by steamy swamps. As plants and trees died, their remains sank to the bottom of the swampy areas building up in layers. Due to the heat and pressure, the particles are compressed together is coal is formed.

  1. Rock types.

    Limestone (a base) reacts with acid to make salt and water in a neutralisation reaction. * When heated in a furnace, it breaks down to quick lime (calcium oxide) and carbon dioxide as metal carbonates decompose on heating. Quick lime (Calcium oxide)

  2. Dovedale - Limestone rocks.

    Karst offers opportunities for scientific study and education, allowing us a window into past environments that may not have changed for thousands of years.

  1. Construct two Graphic Log Sections, one on the eastern exposure (ST 3375 6645) and ...

    Some had been eroded and weathered away making it difficult to recognise them How we collected our fieldwork data is shown in the table below. Analysis and Conclusions Location 1 Eastern Exposure, Middle Hope (ST 3375 6645) Rock Unit Rock Type/ Colour/ Grain size Sedimentary Structures/ Fossils/ Other Explanation on

  2. Gullet Quarry- Igneous Investigation.

    Predictions. I predict that the intrusions were formed at different times and are from different magma sources. Safety. When I am carrying out this investigation I must remember that the quarry is a potentially dangerous environment. A helmet must be worn at all times during the experiment.

  1. Determining the paleoenviroment and tectonic history of a small area (Cocklawburn Beach)

    there have been any compression or tension forces acting on the rock, and also the direction that the forces were coming from. To test these methods I have constructed a short sedimentary log of beach called Cullernose point, which is near Cocklawburn beach, I have found that these methods work

  2. 'I think that sedimentary stones will be more affected by weathering than igneous stones.' ...

    I also discovered some things that I would need on the day: - Clipboard: to lean on/hold paper. - Paper: to write on. - Pen: to write with. - Pencil: to write with in case it rains. - Lens: to help identify stones.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work