Seismic evidence of a regional sublithospheric low velocity layer beneath the Canary Islands

Martı́nez-Arévalo, Carmen; Mancilla, Flor de Lis; Helffrich, George; García, Alicia García

doi:10.1016/j.tecto.2013.08.021

Cited by 40 publications

(39 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the case of El Hierro, bathymetric studies4143, suggest that the volcanic pile is about 5,500 m thick, reaching 1,500 a.s.l. The pre-volcanic sediments would have a thickness of about 500 m, while the oceanic crust would extend down to 12–15 km depth and the lithospheric-asthenosphere boundary would be located at about 50–60 km4445. No evidence of underplating at the crust/mantle discontinuity has been reported at El Hierro94044, as well as no evidence of lithospheric flexure39.…”

Section: Discussionmentioning

confidence: 99%

Stress barriers controlling lateral migration of magma revealed by seismic tomography

Martı́

Villaseñor

Geyer

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Understanding how monogenetic volcanic systems work requires full comprehension of the local and regional stresses that govern magma migration inside them and why/how they seem to change from one eruption to another. During the 2011–2012 El Hierro eruption (Canary Islands) the characteristics of unrest, including a continuous change in the location of seismicity, made the location of the future vent unpredictable, so short term hazard assessment was highly imprecise. A 3D P-wave velocity model is obtained using arrival times of the earthquakes occurred during that pre-eruptive unrest and several latter post-eruptive seismic crises not related to further eruptions. This model reveals the rheological and structural complexity of the interior of El Hierro volcanic island. It shows a number of stress barriers corresponding to regional tectonic structures and blocked pathways from previous eruptions, which controlled ascent and lateral migration of magma and, together with the existence of N-S regional compression, reduced its options to find a suitable path to reach the surface and erupt.

show abstract

Section: Discussionmentioning

confidence: 99%

Stress barriers controlling lateral migration of magma revealed by seismic tomography

Martı́

Villaseñor

Geyer

et al. 2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The advantage of the last method is that it works on the correlated signal and mitigates against noise on the RFs. It has been recommended in the case of oceanic island studies, such as the Cape Verde islands , the Seychelles islands (Hammond et al, 2013), and the Canary islands (Lodge et al, 2012;Martinez-Arevalo et al, 2013), and in our case we choose it for its capacity to remove anthropic noise. To estimate the Moho depth below the island of Haiti, we use the Extended-Time Multitaper Frequency domain Cross-Correlation ReceiverFunction (ETMTRF) technique of Helffrich (2006), which is based on the MTRF method of Park and Levin (2000).…”

Section: Receiver Function Techniquementioning

confidence: 99%

Crustal structure of western Hispaniola (Haiti) from a teleseismic receiver function study

et al. 2017

View full text Add to dashboard Cite

Haiti, located at the northern Caribbean plate boundary, records a geological history of terrane accretion from Cretaceous island arc formations to the Eocene to Recent oblique collision with the Bahamas platform. Little is presently known about the underlying crustal structure of the island. We analyze P-waveforms arriving at 27 temporary broadband seismic stations deployed over a distance of 200 km across the major terrane boundaries in Haiti to determine the crustal structure of western Hispaniola. We compute teleseismic receiver functions using the Extended-Time Multi-Taper method and determine crustal thickness and bulk composition (V p /V s ) using the H-к stacking method. Three distinctive and fault-bounded crustal domains, defined by their characteristic Moho depth distributions and bulk crustal V p /V s , are imaged across Haiti. We relate these domains to three crustal terranes that have been accreted along the plate boundary during the northeastwards displacement of the Caribbean plate and are presently being deformed in a localized fold and thrust belt. In the northern domain, made up of volcanic arc facies, the crust has a thickness of~23 km and Vp/Vs of 1.75 ± 0.1 typical of average continental crust. The crust in the southern domain is part of the Caribbean Large Igneous Province (Caribbean LIP), and is~22 km thick with Vp/Vs of 1.80 ± 0.03 consistent with plume-related rocks of late Cretaceous age. Significantly thicker, the crust in central Haiti has values of Moho depths averaging~41 km and with Vp/Vs of 1.80 ± 0.05. We propose that the central domain is likely constructed of an island arc upper crust with fragments of dense material originating from mafic lavas or LIP material. We produce a crustal profile along a N-S transect across Haiti accounting for the surface geology, shallow structural history, and new seismological constraints provided by variations of crustal thickness and bulk composition.

show abstract

“…The Canary archipelago is an oceanic intraplate hotspot (Morgan, 1972), located ~100 km off the north-west coast of Africa. Although the Canaries have been extensively studied using seismic methods (Bonnin et al, 2014;Lodge et al, 2012;Martinez-Arevalo et al, 2013;Miller et al, 2015;Montelli et al, 2006;van der Meijde et al, 2003), the origin of its underlying anomalous low-velocity mantle is still debated. Global seismic models feature low P-wave velocities suggesting a ~400 km wide mantle plume that extends down into the lowermost mantle (Montelli et al, 2006(Montelli et al, , 2004Zhao, 2004).…”

Section: Introductionmentioning

confidence: 99%

A common deep source for upper-mantle upwellings below the Ibero-western Maghreb region from teleseismic P-wave travel-time tomography

Civiero

Strak

Custódio

et al. 2018

Earth and Planetary Science Letters

View full text Add to dashboard Cite

Upper-mantle upwellings are often invoked as the cause of Cenozoic volcanism in the Ibero-western Maghreb region. However, their nature, geometry and origin are unclear. This study takes advantage of dense seismic networks, which cover an area extending from the Pyrenees in the north to the Canaries in the south, to provide a new high-resolution P-wave velocity model of the upper-mantle and topmost lower-mantle structure. Our images show three subvertical upper-mantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc, which appear to be rooted beneath the upper-mantle transition zone (MTZ). Two other mantle upwellings beneath the eastern Rif and eastern Betics surround the Gibraltar subduction zone. We propose a new geodynamic model in which narrow uppermantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc rise from a laterally-propagating layer of material below the MTZ, which in turn is fed by a common deep source below the Canaries. In the Gibraltar region, the deeply rooted upwelling interacts with the Gibraltar slab. Quasi-toroidal flow driven by slab rollback induces the hot mantle material to flow around the slab, creating the two low-velocity anomalies below the eastern Betics and eastern Rif. Our results suggest that the Central Atlantic plume is a likely source of hot mantle material for upper-mantle upwellings in the Ibero-western Maghreb region.

show abstract

Seismic evidence of a regional sublithospheric low velocity layer beneath the Canary Islands

Cited by 40 publications

References 58 publications

Stress barriers controlling lateral migration of magma revealed by seismic tomography

Stress barriers controlling lateral migration of magma revealed by seismic tomography

Crustal structure of western Hispaniola (Haiti) from a teleseismic receiver function study

A common deep source for upper-mantle upwellings below the Ibero-western Maghreb region from teleseismic P-wave travel-time tomography

Contact Info

Product

Resources

About