Baja California and the Sea of Cortez

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Tijuana

Ensenada

San Quintin

El Rosario

Guerrero Negro

Bahia Magdalena

Cabo San Lucas

La Paz

Bahia Concepcion

Mulege

Santa Rosalia

Bahia de Los Angeles

San Felipe

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Geology of Baja California

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• Pacific Plate moves NW past N. American Plate

• San Andreas fault between

4

Murphy, 1983 as quoted in Grismer, unpublished

tropics

Early Miocene:• Part of shore or underwater• Some mountains as islands

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Murphy, 1983 as quoted in Grismer, unpublished

tropics

Middle Miocene:• Mountains rose• Mainland subsided• Gulf began to form• S. peninsula separated from mainland, became island

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Murphy, 1983 as quoted in Grismer, unpublished

tropics

Late Miocene:• Mountain chains connected, forming a contiguous peninsula

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Murphy, 1983 as quoted in Grismer, unpublished

tropics

Miocene-Pliocene:• Rapid tectonic activity• Pacific plate moved north• Mountains rose more• Sea level rose, isolating south end• Gulf extended far north

8

Murphy, 1983 as quoted in Grismer, unpublished

tropics

Late Pliocene-Present:• Mountain uplift• Desertification• Gulf regressed• Temporary land bridges to islands

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History of Baja California

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Cortez

Gúzman

Mendoza 1532

Becerra 1533

Cortez 1535

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English map1641

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English map 1641

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Cabrillo 1542

Mendoza galleons 1542Francis Drake 1578

Cavendish 1586

Vizcaino 1596

Vizcaino 1602

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