@article {Arroyo2014,
	title = {{Interplate seismicity at the CRISP drilling site: The 2002 Mw 6.4 Osa Earthquake at the southeastern end of the Middle America Trench}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {15},
	number = {7},
	year = {2014},
	pages = {3035{\textendash}3050},
	publisher = {Blackwell Publishing Ltd},
	abstract = {We investigate potential relations between variations in seafloor relief and age of the incoming plate and interplate seismicity. Westward from Osa Peninsula in Costa Rica, a major change in the character of the incoming Cocos Plate is displayed by abrupt lateral variations in seafloor depth and thermal structure. Here a Mw 6.4 thrust earthquake was followed by three aftershock clusters in June 2002. Initial relocations indicate that the main shock occurred fairly trenchward of most large earthquakes along the Middle America Trench off central Costa Rica. The earthquake sequence occurred while a temporary network of OBH and land stations \~{}80 km to the northwest were deployed. By adding readings from permanent local stations, we obtain uncommon P wave coverage of a large subduction zone earthquake. We relocate this catalog using a nonlinear probabilistic approach within both, a 1-D and a 3-D P wave velocity models. The main shock occurred \~{}25 km from the trench and probably along the plate interface at 5-10 km depth. We analyze teleseismic data to further constrain the rupture process of the main shock. The best depth estimates indicate that most of the seismic energy was radiated at shallow depth below the continental slope, supporting the nucleation of the Osa earthquake at \~{}6 km depth. The location and depth coincide with the plate boundary imaged in prestack depth-migrated reflection lines shot near the nucleation area. Aftershocks propagated downdip to the area of a 1999 Mw 6.9 sequence and partially overlapped it. The results indicate that underthrusting of the young and buoyant Cocos Ridge has created conditions for interplate seismogenesis shallower and closer to the trench axis than elsewhere along the central Costa Rica margin. {\textcopyright} 2014. American Geophysical Union. All Rights Reserved.},
	keywords = {earthquake relocation, erosional margin, interplate drilling},
	issn = {15252027},
	doi = {10.1002/2014GC005359},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84906266765\&partnerID=tZOtx3y1},
	author = {Arroyo, Ivonne G. and Grevemeyer, Ingo and Ranero, Cesar R. and von Huene, Roland}
}
@article {Sallares2013a,
	title = {{Overriding plate structure of the Nicaragua convergent margin: Relationship to the seismogenic zone of the 1992 tsunami earthquake}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {14},
	number = {9},
	year = {2013},
	month = {sep},
	pages = {3436{\textendash}3461},
	abstract = {We present 2-D seismic velocity models and coincident multichannel seismic reflection images of the overriding plate and the inter-plate boundary of the Nicaragua convergent margin along two wide-angle seismic profiles parallel and normal to the trench acquired in the rupture area of the 1992 tsunami earthquake. The trench-perpendicular profile runs over a seamount subducting under the margin slope, at the location where seismological observations predict large coseismic slip. Along this profile, the igneous basement shows increasing velocity both with depth and away from the trench, reflecting a progressive decrease in upper-plate rock degree of fracturing. Upper mantle-like velocities are obtained at \~{}10 km depth beneath the fore-arc Sandino basin, indicating a shallow mantle wedge. A mismatch of the inter-plate reflector in the velocity models and along coincident multichannel seismic profiles under the slope is best explained by \~{}15\% velocity anisotropy, probably caused by subvertical open fractures that may be related to fluid paths feeding known seafloor seepage sites. The presence of a shallow, partially serpentinized mantle wedge, and the fracture-related anisotropy are supported by gravity analysis of velocity-derived density models. The downdip limit of inter-plate seismicity occurs near the tip of the inferred mantle wedge, suggesting that seismicity could be controlled by the presence of serpentinite group minerals at the fault gouge. Near the trench, the inferred local increase of normal stress produced by the subducting seamount in the plate boundary may have made this fault segment unstable during earthquake rupture, which could explain its tsunamigenic character. {\textcopyright} 2013. American Geophysical Union. All Rights Reserved.},
	keywords = {Convergent margin, travel time tomography, tsunami earthquake, wide-angle seismics},
	issn = {15252027},
	doi = {10.1002/ggge.20214},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84886671506\&partnerID=tZOtx3y1},
	author = {Sallares, Valenti and Mel{\'e}ndez, Adri{\`a} and Prada, Manuel and Ranero, Cesar R. and McIntosh, Kirk and Grevemeyer, Ingo}
}
@article {Dannowski2010,
	title = {{Seismic structure of an oceanic core complex at the Mid-Atlantic Ridge, 22{\textdegree}19'N}},
	journal = {Journal of Geophysical Research},
	volume = {115},
	number = {B7},
	year = {2010},
	month = {jul},
	pages = {B07106},
	abstract = {We present results from a seismic refraction and wide-angle experiment surveying an oceanic core complex on the Mid-Atlantic Ridge at 2219N. Oceanic core complexes are settings where petrological sampling found exposed lower crustal and upper mantle rocks, exhumed by asymmetric crustal accretion involving detachment faulting at magmatically starved ridge sections. Tomographic inversion of our seismic data yielded lateral variations of P wave velocity within the upper 3 to 4 km of the lithosphere across the median valley. A joint modeling procedure of seismic P wave travel times and marine gravity field data was used to constrain crustal thickness variations and the structure of the uppermost mantle. A gradual increase of seismic velocities from the median valley to the east is connected to aging of the oceanic crust, while a rapid change of seismic velocities at the western ridge flank indicates profound differences in lithology between conjugated ridge flanks, caused by un-roofing lower crust rocks. Under the core complex crust is approximately 40\% thinner than in the median valley and under the conjugated eastern flank. Clear PmP reflections turning under the western ridge flank suggest the creation of a Moho boundary and hence continuous magmatic accretion during core complex formation.Copyright 2010 by the American Geophysical Union.},
	issn = {0148-0227},
	doi = {10.1029/2009JB006943},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955209693\&partnerID=tZOtx3y1},
	author = {Dannowski, Anke and Grevemeyer, Ingo and Ranero, Cesar R. and Ceuleneer, Georges and Maia, Marcia and Morgan, Jason Phipps and Gente, Pascal}
}
@article {Harris2010a,
	title = {{Thermal regime of the Costa Rican convergent margin: 1. Along-strike variations in heat flow from probe measurements and estimated from bottom-simulating reflectors}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {11},
	number = {12},
	year = {2010},
	month = {dec},
	pages = {n/a{\textendash}n/a},
	abstract = {The thermal structure of convergent margins provides information related to the tectonics, geodynamics, metamorphism, and fluid flow of active plate boundaries. We report 176 heat flow measurements made with a violin bow style probe across the Costa Rican margin at the Middle America Trench. The probe measurements are collocated with seismic reflection lines. These seismic reflection lines show widespread distribution of bottom-simulating reflectors (BSRs). To extend the spatial coverage of heat flow measurements we estimate heat flow from the depth of BSRs. Comparisons between probe measurements and BSR-derived estimates of heat flow are generally within 10\% and improve with distance landward of the deformation front. Together, these determinations provide new information on the thermal regime of this margin. Consistent with previous studies, the margin associated with the northern Nicoya Peninsula is remarkably cool. We define better the southern boundary of the cool region. The northern extent of the cool region remains poorly determined. A regional trend of decreasing heat flow landward of the deformation front is apparent, consistent with the downward advection of heat by the subducting Cocos Plate. High wave number variability at a scale of 5-10 km is significantly greater than the measurement uncertainty and is greater south of the northern Nicoya Peninsula. These heat flow anomalies vary between approximately 20 and 60 mW m-2 and are most likely due to localized fluid flow through mounds and faults on the margin. Simple one-dimensional models show that these anomalies are consistent with flow rates of 7-15 mm yr-1. Across the margin toe variability is significant and likely due to fluid flow through deformation structures associated with the frontal sedimentary prism. Copyright 2010 by the American Geophysical Union.},
	keywords = {fluid flow, heat flow, Middle America Trench, subduction zones},
	issn = {15252027},
	doi = {10.1029/2010GC003272},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-78650544794\&partnerID=tZOtx3y1},
	author = {Harris, Robert N. and Grevemeyer, Ingo and Ranero, Cesar R. and Villinger, Heinrich and Barckhausen, Udo and Henke, Thomas and Mueller, Christian and Neben, Soenke}
}
@article {Harris2010,
	title = {{Thermal regime of the Costa Rican convergent margin: 2. Thermal models of the shallow Middle America subduction zone offshore Costa Rica}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {11},
	number = {12},
	year = {2010},
	month = {dec},
	pages = {n/a{\textendash}n/a},
	abstract = {At the Costa Rica margin along the Middle America Trench along-strike variations in heat flow are well mapped. These variations can be understood in terms of either ventilated fluid flow, where exposed basement allows fluids to freely advect heat between the crustal aquifer and ocean, or insulated fluid flow where continuous sediment cover restricts heat advection to within the crustal aquifer. We model fluid flow within the subducting aquifer using Nusselt number approximations coupled with finite element models of subduction and explore its effect on temperatures along the subduction thrust. The sensitivity of these models to the initial thermal state of the plate and styles of fluid flow, either ventilated or insulated, is explored. Heat flow measurements on cool crust accreted at the East Pacific Rise are consistent with ventilated hydrothermal cooling that continues with subduction. These models yield much cooler temperatures than predicted from simulations initialized with conductive predictions and without hydrothermal circulation. Heat flow transects on warm crust accreted at the Cocos-Nazca spreading center are consistent with models of insulated hydrothermal circulation that advects heat updip within the subducting crustal aquifer. Near the trench these models are warmer than conductive predictions and cooler than conductive predictions downdip of the trench. Comparisons between microseismicity and modeled isotherms suggest that the updip limit of microseismicity occurs at temperatures warmer than 100{\textdegree}C and that the downdip extent of microseismicity is bounded by the intersection of the subduction thrust with the base of the overriding crust. Copyright 2010 by the American Geophysical Union.},
	keywords = {fluid flow, subduction zones, thermal model},
	issn = {15252027},
	doi = {10.1029/2010GC003273},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-78650528793\&partnerID=tZOtx3y1},
	author = {Harris, Robert N. and Spinelli, Glenn and Ranero, Cesar R. and Grevemeyer, Ingo and Villinger, Heinrich and Barckhausen, Udo}
}
@article {Grevemeyer2007,
	title = {{Passive and active seismological study of bending-related faulting and mantle serpentinization at the Middle America trench}},
	journal = {Earth and Planetary Science Letters},
	volume = {258},
	number = {3-4},
	year = {2007},
	month = {jun},
	pages = {528{\textendash}542},
	abstract = {Water transported within the subducting oceanic lithosphere into the Earth{\textquoteright}s interior affects a wealth of subduction zone processes, including intraslab earthquakes and arc magmatism. In recent years growing evidence suggests that much of the hydration of oceanic plates occurs at the trench-ocean slope right before subduction. Here, normal faults are created while the rigid lithosphere bends into the trench. Offshore of Middle America, multi-channel seismic reflection imaging suggests that bending-related faults cut into the uppermost mantle, providing a mechanism for hydration and transformation of mantle peridotites into serpentinites. Seismic wide-angle reflection and refraction data were collected coincident with one of the seismic profiles where the faults have been imaged. Travel time inversion provides evidence that both crustal and uppermost mantle velocities are reduced with respect to the velocity structure found in mature oceanic crust away from deep-sea trenches. If mantle velocity reduction is solely produced by hydration, velocities indicate 10-15\% of serpentinization in the uppermost 3~km of the mantle, where seismic data provide enough resolution. A small network of ocean bottom hydrophones, deployed for about a month, detected \~{} 3 local micro earthquakes per day. Earthquake epicentres align with fault scarps at the seafloor and continuous earthquake activity might be an important process to facilitate the percolation of seawater into the upper mantle. {\textcopyright} 2007 Elsevier B.V. All rights reserved.},
	keywords = {bending-related normal faulting, earthquakes, global water cycle, seismic refraction, serpentinization, subduction},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2007.04.013},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-34249911517\&partnerID=tZOtx3y1},
	author = {Grevemeyer, Ingo and Ranero, Cesar R. and Flueh, Ernst R. and Kl{\"a}schen, Dirk and Bialas, J{\"o}rg}
}
