Geology and tectonics of the Baja California Peninsula and adjacent areas

Sedlock, Richard L.

doi:10.1130/0-8137-2374-4.1

Cited by 29 publications

(29 citation statements)

References 137 publications

(311 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus a Farallon-Caribbean Plate boundary is required unless the Pacific hot spots were migrating to the NW relative to the Indo-Atlantic hot spots faster than 75-100 km/Ma, which is unlikely. In the NW, this boundary was probably the site of south-dipping subduction, possibly explaining the Aptian-Albian onset of arc magmatism in the Alisitos Arc in Baja California (Sedlock 2003), which we show outboard of the Sonora-Sinaloa Arc (Henry et al 2003) and the Zihuatanejo Arc where Farallon-cum-Caribbean crust continued to be subducted. Southwards along this new boundary in Costa Rica to Panama, Farallon-Caribbean motion could have been accommodated along an oceanic transform that would become the site of east-dipping subduction only after a dramatic turn in Farallon-Americas motion at c. 84 Ma.…”

Section: Plate Reconstructions and Reference Framesmentioning

confidence: 48%

“…A good candidate is the intra-oceanic Alisitos Arc of Baja California (Sedlock 2003), which initiated at about 125 Ma probably not far from the continent (explaining the presence of older detrital zircons in associated volcaniclastic sediments) and accreted to the Mexican margin by 105 Ma. Between 125 Ma and eruption of the Caribbean LIP at c. 90 Ma the subduction of 750-1500 km of Farallon crust beneath the NW Caribbean would not prevent the eruption of plume-derived plateau basalts further south.…”

Section: Initiation Of the Western Caribbean Plate Boundarymentioning

confidence: 99%

See 1 more Smart Citation

Tectonic evolution of the Gulf of Mexico, Caribbean and northern South America in the mantle reference frame: an update

Pindell

Kennan²

2009

577

627

View full text Add to dashboard Cite

We present an updated synthesis of the widely accepted 'single-arc Pacific-origin' and 'Yucatán-rotation' models for Caribbean and Gulf of Mexico evolution, respectively. Fourteen palaeogeographic maps through time integrate new concepts and alterations to earlier models. Pre-Aptian maps are presented in a North American reference frame. Aptian and younger maps are presented in an Indo-Atlantic hot spot reference frame which demonstrates the surprising simplicity of Caribbean-American interaction. We use the Müller et al. (Geology 21: 275-278, 1993) reference frame because the motions of the Americas are smoothest in this reference frame, and because it does not differ significantly, at least since c. 90 Ma, from more recent 'moving hot spot' reference frames. The Caribbean oceanic lithosphere has moved little relative to the hot spots in the Cenozoic, but moved north at c. 50 km/Ma during the Cretaceous, while the American plates have drifted west much further and faster and thus are responsible for most CaribbeanAmerican relative motion history. New or revised features of this model, generally driven by new data sets, include: (1) refined reconstruction of western Pangaea; (2) refined rotational motions of the Yucatán Block during the evolution of the Gulf of Mexico; (3) an origin for the Caribbean Arc that invokes Aptian conversion to a SW-dipping subduction zone of a trans-American plate boundary from Chortís to Ecuador that was part sinistral transform (northern Caribbean) and part pre-existing arc (eastern, southern Caribbean); (4) acknowledgement that the Caribbean basalt plateau may pertain to the palaeo-Galapagos hot spot, the occurrence of which was partly controlled by a Proto-Caribbean slab gap beneath the Caribbean Plate; (5) Campanian initiation of subduction at the Panama-Costa Rica Arc, although a sinistral transform boundary probably pre-dated subduction initiation here; (6) inception of a north-vergent crustal inversion zone along northern South America to account for Cenozoic convergence between the Americas ahead of the Caribbean Plate; (7) a fan-like, asymmetric rift opening model for the Grenada Basin, where the Margarita and Tobago footwall crustal slivers were exhumed from beneath the southeast Aves Ridge hanging wall; (8) an origin for the Early Cretaceous HP/LT metamorphism in the El Tambor units along the Motagua Fault Zone that relates to subduction of Farallon crust along western Mexico (and then translated along the trans-American plate boundary prior to onset of SW-dipping subduction beneath the Caribbean Arc) rather than to collision of Chortis with Southern Mexico; (9) Middle Miocene tectonic escape of Panamanian crustal slivers, followed by Late Miocene and Recent eastward movement of the 'Panama Block' that is faster than that of the Caribbean Plate, allowed by the inception of east-west trans-Costa Rica shear zones. The updated model integrates new concepts and global plate motion models in an internally consistent way, and can be used to test and guide more local ...

show abstract

Section: Plate Reconstructions and Reference Framesmentioning

confidence: 48%

Section: Initiation Of the Western Caribbean Plate Boundarymentioning

confidence: 99%

Tectonic evolution of the Gulf of Mexico, Caribbean and northern South America in the mantle reference frame: an update

Pindell

Kennan²

2009

577

627

View full text Add to dashboard Cite

show abstract

“…The location of the deepest seismic events correlates perfectly with the location of the lowest heat flow. Unlike the SN, the granitic rocks of the PB are chiefly tonalites and granodiorites with very low radiogenic heat production [Sedlock, 2003]. The radiogenic heat productions values are in the range of 0.5-1.3 mW m…”

Section: à2mentioning

confidence: 99%

Transient thermal regimes in the Sierra Nevada and Baja California extinct outer arcs following the cessation of Farallon subduction

Erkan

Blackwell

2009

J. Geophys. Res.

View full text Add to dashboard Cite

[1] We examine the thermal relaxation of the Sierra Nevada and Baja California extinct outer arc blocks following the progressive cessation of Farallon subduction under western North America beginning at $30 Ma. Being parts of the same outer arc until the inland jump of the San Andreas transform fault at $5 Ma, these two regions show many similarities in their geology, geomorphology, rigid body behavior, and their relatively low seismicity. In the thermal model, we combine results of different geophysical and geophysical studies to constrain the thermal state and geometry of the outer arcs before the cessation of subduction and then model the postsubduction temperature responses in these regions using the results of the tectonic reconstructions. A well-constrained regional thermal model of these blocks using the results of many earlier studies in these regions confirms that the present low heat flow values in these regions are the remnants of the very cold outer arc thermal regime of the subduction zone even as long as 30 Ma after cessation of subduction. Thus the entire Pacific boundary of the North American plate is still in a transient thermal state. The calculated low lithospheric temperatures in the Sierra Nevada and Peninsular blocks correlate very well with their rigid body behavior obtained from geodetic studies, and seismogenic layer thicknesses obtained from seismological studies. This is in contrast with the fact that both regions are surrounded by intense deformation associated with the western North America intraplate and extraplate motions. These low-temperature islands play important roles in the present interaction of the North American and Pacific plates and contribute to the broad deformation of the transform boundary. The thermal relaxation of the extinct outer arcs includes both vertical heating from the underlying asthenosphere and the lateral heating from the extinct back arc (Basin and Range), which has remained as a high heat flow region after the cessation of the subduction. We suggest that the significant lateral heat transfer from the Basin and Range in the Sierra Nevada (and from the Gulf of California spreading center in the Peninsular block since $5 Ma) may be the main driving mechanism of the postsubduction volcanism/magmatism along the extinct volcanic arc and the recent tilted uplift of the Sierra Nevada block. The low lithospheric temperatures in Sierra Nevada region may also explain the observation of the high seismic velocities in the mantle beneath the southern Sierra Nevada where the downwelling of the mantle lithosphere proposed.

show abstract

“…The proposed suture divides the magnetite-series, Early Cretaceous plutons and host crust of the Western Peninsula Ranges Batholith from the ilmenite-series mid-Cretaceous plutons and crust of the Eastern Peninsula Ranges Batholith. The significance of this suture (as with the Eastern Palmer Land Shear Zone) has been interpreted as representing exotic terrane accretion, accretion of a fringing arc or heterogeneities within a single arc (Sedlock 2003, and references therein). However, as with the Antarctic Peninsula granitoids, the similar pattern of ilmenite-and magnetite-series plutons may be related to suprasubduction-zone processes, with magnetite-series intrusions occurring in the extended crust close to the convergent margin and the ilmenite-series produced by increased crustal assimilation inland.…”

Section: Baja California and The North American Pacific Coastmentioning

confidence: 99%

Autochthonous v. accreted terrane development of continental margins: a revised in situ tectonic history of the Antarctic Peninsula

Burton‐Johnson

Riley

2015

JGS

View full text Add to dashboard Cite

The allochthonous terrane accretion model previously proposed for the geological development of the Antarctic Peninsula continental margin arc is reviewed in light of recent data and the geology is reinterpreted as having evolved as an in situ continental arc. This is based upon the following factors: (1) the presence of Early Palaeozoic basement and stratigraphic correlation of sequences between the autochthonous and previously proposed allochthonous terranes; (2) isotopic evidence for similar deep crustal structure across the different terranes; (3) ocean island basalt magmas and deep marine sedimentary rocks formed during continental margin extension within the previously proposed accretionary wedge sequence (i.e. not formed against an active oceanic arc); (4) the distribution of magnetic susceptibility measurements and aeromagnetic data locating the palaeo-subduction zone along the west of the Peninsula; (5) a lack of clear palaeomagnetic distinction between the terranes. The following alternative tectonic history is proposed: (1) amalgamation and persistence of Gondwana; (2) subsequent silicic large igneous province magmatism and extension; (3) development and history of Andean subduction until its cessation in the Cenozoic. A number of features in the Antarctic Peninsula correlate with those of other circum-Pacific margins, supporting a global evaluation of allochthonous v. autochthonous margin development to aid our understanding of crustal growth mechanisms.

show abstract

Geology and tectonics of the Baja California Peninsula and adjacent areas

Cited by 29 publications

References 137 publications

Tectonic evolution of the Gulf of Mexico, Caribbean and northern South America in the mantle reference frame: an update

Tectonic evolution of the Gulf of Mexico, Caribbean and northern South America in the mantle reference frame: an update

Transient thermal regimes in the Sierra Nevada and Baja California extinct outer arcs following the cessation of Farallon subduction

Autochthonous v. accreted terrane development of continental margins: a revised in situ tectonic history of the Antarctic Peninsula

Contact Info

Product

Resources

About