Settling and Coelescence

Sandstone layering

Particles suspended in water tend to settle from the pull of gravity before coming to rest against some barrier. The settling and coalescence of Earth's fine-grained material is called sedimentation.

Sedimentation and erosion are poetically reciprocal phenomena.

If erosion is the breaking loose, suspension, and movement of particles via water, then sedimentation is the terminal end of that movement where suspended and transported particles settle out to come to rest.

"The question is, of course, is it going to be possible to amalgamate everything, and merely discover that this world represents different aspects of one thing?"
― Richard Feynman, The Feynman Lectures on Physics

Sedimentary Rocks

Sedimentary rocks form by the settling of Earth's fine-grained material. Earth's fine-grained material occurs from weathering and erosion. Sedimentary rocks cover much of Earth's continents, yet the volumetric contribution of sedimentary rocks to the total volume of Earth's crust is only about 8 percent.

Lateral Continuity

The result of the settling of particles or deposition of particles is the formation of new depositional landforms. These landforms are often observed in a lateral or horizontal plane. The lateral plane is orthogonal to the direction of gravitational pull.

Sedimentary rocks separated by a valley

Layers of sediment extending laterally in all directions are said to have lateral continuity (cf. The Principle of Lateral Continuity). Sometimes the lateral plane appears to be tilted or has been interrupted by other forces.

"Curiosity demands that we ask questions, that we try to put things together and try to understand this multitude of aspects as perhaps resulting from the action of a relatively small number of elemental things and forces acting in an infinite variety of combinations."
― Richard Feynman, The Feynman Lectures on Physics

REFERENCES

• A Simple Formula to Estimate Settling Velocity of NaturalSediments, Jose´ A. Jime´nez1 and Ole S. Madsen, Journal of Waterway, Port, Coastal and Ocean Engineering © ASCE, March/April 2003.
• Erosion, Wikipedia.
• Principle of Lateral Continuity, Wikipedia.
• Sedimentary Rock, Wikipedia.
• Sedimentation, Wikipedia.
• The Feynman Lectures on Physics, Richard P. Feynman

The Nature of Sea Levels

Sea Surface by Petr Kratochvil

Sea level is the average height of the ocean's surface. Sea levels have fluctuated over time.

Measurement

Mean Sea Level is a way to express the elevation of the sea with wave motion and tide changes averaged out.

Geologic observation and artifacts narrate the story of the oceans.

Constant Change

Bermuda

Sea level fluctuations are preserved in the geologic record.

Sedimentary and fossil records are often the key to estimating historic sea levels. Coral reefs are also accurate markers because they grow just below the prevailing sea level of the time.

There is sedimentary and fossil evidence that sea level was more than 21 meters (70 ft) higher 400,000 years ago than it is today:

...sedimentary and fossil evidence in the walls of a limestone quarry in Bermuda that documents a rise in sea level during an interglacial period of the Middle Pleistocene in excess of 21 meters above its current level. ~ Dramatic Rise In Sea Level And Its Broad Ramifications Uncovered

Ocean and Continents

Western Interior Seaway

The notion of the familiar borders between oceans and continents seems static within the time scale of a human lifetime. Over a geologic timescale, oceans and continents appear ever-changing.

Even Castles made of sand, fall into the sea, eventually.
~ Jimi Hendrix

The Western Interior Seaway was an inland sea that divided North American into two landmasses during the Mid-to-Late Cretaceous period. Vast carbonate deposits indicate the Seaway was warm and tropical.

The shallow Western Interior Seaway supported abundant marine life and early birds.

References

• Dramatic Rise In Sea Level And Its Broad Ramifications Uncovered. ScienceDaily, February 9, 2009.
• Exceptionally Rapid Ancient Sea Level Rise Illuminates Rate of Coming Changes. TreeHugger, June 6, 2012.
• New Study Lowers Estimate of Ancient Sea-Level Rise. ScienceDaily, March 14, 2012.
• Sea Levels Much Less Stable Than Earlier Believed, New Coral Dating Method Suggests. ScienceDaily, September 11, 2011.
• Significant Sea-Level Rise in a Two-Degree Warmer World. ScienceDaily, June 24, 2012.
• Western Interior Seaway. Wikipedia.