Geology

Picacho del Diablo (10,154') in the Sierra San Pedro Martir range to the west of San Felipe.

This page contains but a hint of what it took to create the place many San Felipeños think of as Paradise. It was created as a condensation of a vast amount of information normally found in public, private and university libraries. Everything appearing below was taken from Scientific American magazine, Archeology magazine, National Geographic magazine, a number of geology text books, and books published by respected scientists.

At the beginning of this presentation, it should be recognized that a significant portion of what the scientific community knows about our Earth, principally speaking of the Theory of Plate Tectonics, was gained during the twentieth century. Formerly, as stated by J. Tuzo Wilson in his Continents Adrift and Continents Aground, “…most scientists thought of the earth as a rigid body with fixed continents and permanent ocean basins although most scientists now agree the brittle surface of the earth is broken into six large plates and several smaller ones which very slowly move and jostle one another like blocks of ice on a river that is breaking up in the spring thaw. “They believe that the thin plates of this surface layer are floating on a deeper layer that is slowly deformable. Each continent does not constitute one plate, but rather each is incorporated with surrounding ocean floor into a plate that is larger than the continent, just as a raft of logs may be frozen into a sheet of ice. These plates have repeatedly collided and joined, broken apart, and rejoined in different patterns. As they have done so, ocean floors have been reabsorbed, but the continents have been modified and remain. These new discoveries have united geological and geophysical studies in a way not possible before.”

A National Geographic magazine edition, some twenty years ago, presented an article describing Alaska as an accumulation of the remains of as many as fifty ancient plates. The following was taken from the April 1992 edition of Scientific American magazine: “When German meteorologist Alfred L. Wegener proposed the idea of continental drift in 1912, he claimed that all the continents were fragments of a single, ancient landmass called Pangaea. The authors [of Mountain Belts and the Supercontinent Cycle – J Brendan Murphy and R. Damian Nance] believe such super continents have formed repeatedly in a tectonic cycle that lasts about 500 million years. They cite as evidence the location and structure of folded and volcanic mountain belts. Every 500 million years the continents assemble into a single landmass. The tectonic interactions associated with the formation and breakup of such super continents provide a new way to view the origin of mountain belts.”

The Paleozoic Era – Among the several tectonic plates forming Earth’s surface, the eastward moving Pacific and westward moving Continental plates collided in such a manner that the smaller Caribbean and Cocos plates were sandwiched between them causing the formation of southern Mexico and Central America and, ultimately, causing a change in the direction the Pacific plate was moving. Subsequently, as a direct result of this collision, the Pacific began a counterclockwise rotation largely responsible a) for the distribution of the Hawaiian Islands; b) for the creation of the San Andreas Fault; and c) the creation of the Baja California peninsula (a splinter of the Continental plate now attached to the Pacific plate and extending as far north as Point Reyes (north of San Francisco).

The Mesozoic Era – During the creation of southern Mexico and Central America, volcanic islands appeared in what may be called the ancient sea. At least one of those islands is visible today at the southern edge of Baja California’s Laguna Salada. Colored black by an estimated 200 million years of exposure to the sun, the remains of a once proud volcano stand along the east side of the highway where it connects to the land after crossing the Laguna. Another part of that same ancient volcano can be seen about a mile west of the same highway. Judging by these remnants, it is fair too estimate a volcano somewhat more than twenty miles in diameter.

The Cenozoic Era – The Geological Society of America, Inc. Memoir 140 contains a description of the tearing of the San Andreas Fault through the stalled Cocos Plate resulting in a portion of that plate becoming permanently attached to the Pacific Plate. We now call the most visible portion of the Cocos “Baja California.”. According to James Michener in his “Mexico,” indigenous man arrived some three thousand years ago during a small hunter-gatherer group’s search for a better place to live, raise children, and eke out an acceptable survival.