theImage.com     Notes on Basic Geology
Notes created & information organization based on the book:
"The Dynamic Earth - an introduction to physical geology"
Brian Skinner & Stephen C. Porter   (further book information here)
also look at www.wiley.com for additional resource information
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Dynamic Earth - Page 5

The 3 interlocking cycles of geology
1.) Hydrology Cycle This cycle follows water in its three states, gaseous, liquid, and solid. It is powered by solar energy and gravity, and is responsible for weathering and erosion.
2.) Rock Cycle This cycle describes the basic building blocks of the earth, and how they are formed, changed, and reformed. It is powered by internal processes and solar processes (sedimentation).
3.) Tectonic Cycle A description of the internal mechanisms at work in forming new crust, and changing modifying the existing crust via internal processes in the lower reaches of the planet.
The three processes overlap with one another and create the entire environment that describes the science of Physical Geology.

Hydrology Cycle

Solar energy provides the heat necessary to evaporate water and create a gaseous phase. The water moves up into the earth's atmosphere and partially condenses to form a layer of clouds.

After further condensation, the water (liquid phase) forms droplets or ice which fall back to the earth in the form of rain or snow.

The water strikes the ground and coalesces to form streams, rivers, snow fields or glaciers. Gravity pulls the water from higher elevation to lower elevation providing it with the energy to erode solid surfaces.

Eventually the water is stored in a reservoir (the ocean, a glacier, or lake) where it may continue its action of erosion by wave action or percolation (dissolution).

Water is also captured by plants which my return it to the air via transpiration.

It may be part of a freeze and thaw cycle which can break rock by expanding and contracting in small fissures.

Finally the largest reservoir, the ocean, is responsible for most of the weather patterns on the earth which also produce wind and provide a means for further erosion.
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