Pacific Ocean expansion on each side of the East Pacific Rise commenced near Antarctica and moved north to intercept the Gulf of California. To the East of the Rise, expansion moved blocks in the Basin and Range terrain in the Rockies to accommodate expansion. To the West the Pacific Ocean expanded. The Rise backfilled the Central American Trench as it neared the coast, and expansion westwards widened the Ocean. The acute angle intercept is to the East and the obtuse intercept to the West. The rise intercepted the coast at the Gulf of California and became the San Andreas Fault as it extended north into California.

The East Pacific Rise

Ernest Wilson

Bucher investigated the pattern of deformation of a spherical crust in tension. A thin spherical glass shell was filled with water and cooled slowly until it expanded on freezing and cracked the glass producing two fractures from a point that we call the North Pole (the “FOCAL BAR” in Figure 1) to the Equator.

The Expanding Earth - Figure 1

Two Hundred Million Years ago the Earth had a spherical crust overlying a plastic interior and expansion induced tension in the Crust and opened two fractures, The 40 W Meridian fracture widened to become the North Atlantic Ocean, and the East Asian fracture, about 140E Meridian, was associated with volcanism as North America to move away from Asia.

In the Southern Hemisphere expansion moved the continents radially away from Antarctica as shown in Figure 2

The Expanding Earth - Figure 2

EGW 21/05/2015