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Oceanic Tides: A Response to Differential Force
throughout the Earth's History

My undergraduate thesis in physics at Carleton College (2001) was an overview
of the basic forces that give rise to tides, and how the tides signature is manifested on earth,
and, consequently, in the sedimentary rock record.

Some of the analysis was incorporated into a paper published in the
Journal of Sedimentary Research by Tape, Cowan, and Runkel (pdf).

Thesis abstract:
Oceanic tides arise from a differential force on the earth due to the moon and sun, as the earth and moon revolve about their common center of mass.  I discuss how differential force arises in an object and then address the earth-moon system.  I examine tides at a global scale, an ocean scale, and a coastal scale.  Finally I show how sedimentary rock layers preserve ancient tidal cycles and provide insight into the earth-moon distance over the course of the earth's history.

The thesis (PDF) can be downloaded here:
Full thesis (16 MB) (91 p.)

A supplement of notes
(PDF) can be downloaded here:
Supplement (3 MB) (26 p.)

Other links:
Carleton College
Carleton Physics Department

Carleton Geology Department


Cambrian sandstone outcrop near Homer, Minnesota (Fig. 32 of thesis).
The systematic thickening and thinning of the layers records the ancient tidal cycles.


Reference frames and coordinate systems for the tides problem (Fig. 6 of thesis).

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