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Mexican CordilleraMexican Cordillera

References:DNAG volume A, Ch. 9 Condie, K.C., 1993, Plate Tectonics and Crustal Evolution, pp. 266-269

Plate Evolution of Mexico Plate Evolution of Mexico and Caribbeanand Caribbean

� Separation of North America from Africa and South America

� Opening of the North Atlantic� Development of the Antilles arc� Growth of the Panama arc and Cayman

transform� Gulf of California opened; Hispaniola

and Puerto Rico moved eastward

Condie (1993)

North America, Africa, and South America were joined in Early Jurassic

Condie (1993)

North America began to rift in mid-Jurassic as North Atlantic opened

Condie (1993)

In Early Cretaceous the proto-Caribbean Basin opened

Condie (1993)

By Late Cretaceous spreading ended and Greater Antilles arc developed

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Condie (1993)

In Early Tertiary Yucatan Basin and Cayman ridge transform developed

Condie (1993)

By Late Tertiary Panama arc grew & Gulf of California opened

Morphotectonic ProvincesMorphotectonic Provinces

� Pacific Ocean Floor

� Pacific Plate

� East Pacific Rise

� Rivera Plate

� Cocos Plate

East Pacific RiseEast Pacific Rise

� En echelon transforms in Gulf of California

� Depth of ~3,000 m

� Orozco FZ

� Spreading rate 9 cm/yr (E-W motion)

Rivera PlateRivera Plate� Rivera fracture

Zone

� Tamayo Fracture Zone

� Continental thrust

� 6 cm/yr plate motion S22E

� Convergence rate 2 cm/yr

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� Middle American Trench� >5000 m deep� 6-7 cm/yr convergence

� Tehuantepec Fracture Zone

Cocos Cocos PlatePlate Gulf of CaliforniaGulf of California

� 1,200 km long and ~150 km wide

� Consists of 9 deep (4,00-5,000 m) basins

� Alluvial/marine fill of nearly 5,000 m

� M discontinuity at only 6 km depth

� ~500 km of rifting of Baja from Mexico

� Resulted from sea floor spreading and transform faulting that began in Late Miocene

Baja PeninsulaBaja Peninsula� Extends from Transverse Ranges to Cabo San

Lucas (1,450 km)� Three parts

� North: Peninsular Ranges� Middle: Sierra La Gigante volcanic plateau� South: Granite and metamorphic terrain

Sonoran Basin and RangeSonoran Basin and Range� Basement is 1.750 Ma schists, gneisses

and granites

� Youngest Proterozoic ~4 km thick quartzite and dolomite

� Paleozoic miogeocline ~2 km quartzite dolomite, limestone, sandstone.

� Mesozoic continental clastic and volcaniclastic sequences

Sierra Madre Sierra Madre OccidentalOccidental

� Volcanic Plateau 1,200 km long and ~ 3 km thick

� Lower volcanic complex ~ 100-45 Ma batholiths and associated extrusive rocks (andesites) 1,000 �1,400 m thick

� Upper volcanic supergroup ~34-27 Ma ignimbrites and calderas 600-800 m thick

Sierra Madre Sierra Madre OrientalOriental

� Folded and thrusted lower Cretaceous carbonates and upper Cretaceous flysch

� Only rare outcrops of older and deeper rocks

� High-level granitic stocks emplaced in the late Eocene

� Block faulting and some basic volcanism in the Miocene

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Sierra Madre Sierra Madre del Surdel Sur

� ~ 1 Ga granulite basement similar to that of S.M. Oriental

� Acatlán Complex (~15 km) of west-dipping metamorphic rocks and ophilolites (Cam.-Dev.) sutured to the craton

Sierra Madre del Sierra Madre del SurSur

� Jurassic continental clastic rocks and volcanics

� Late Cretaceous-Eocene deformation similar to S.M. Oriental

� Early Tertiary continental sediments and Late Tertiary volcanic rocks (andesites).

Sierra de ChiapasSierra de Chiapas� Chiapas Massif -

Devonian batholith

� Upper Paleozoic deep marine sediments

Sierra de ChiapasSierra de Chiapas

� Triassic redbeds overlain by Cretaceous limestones

� Paleocene-Miocene ls, sh, ss (12,000 m)

� Early Miocene folding and thrusting towards SW

Trans Mexican Volcanic BeltTrans Mexican Volcanic Belt� East-West belt of Quaternary volcanoes

� High plateau (~2,300 masl)

� Stratovolcanoes & monogenetic volcanic fields

StratovolcanoesStratovolcanoes� Tepic� Colima� Ceboruco� Nevado de Toluca� Popocatépetl� La Malinche� Pico de Orizaba

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Monogenetic Basaltic FieldsMonogenetic Basaltic Fields

� Michoacan-Guanajuato field

� Chichinautzin

� Scattered fields of basaltic cones and lavas