@article {Dannowski2011,
	title = {{Crustal structure of the propagating TAMMAR ridge segment on the Mid-Atlantic Ridge, 21.5{\textdegree}N}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {12},
	number = {7},
	year = {2011},
	month = {jul},
	pages = {n/a{\textendash}n/a},
	abstract = {Active ridge propagation frequently occurs along spreading ridges and profoundly affects ridge crest segmentation over time. The mechanisms controlling ridge propagation, however, are poorly understood. At the slow spreading Mid-Atlantic Ridge at 21.5{\textdegree}N a seismic refraction and wide-angle reflection profile surveyed the crustal structure along a segment controlled by rapid ridge propagation. Tomographic traveltime inversion of seismic data suggests that the crustal structure along the ridge axis is controlled by melt supply; thus, crust is thickest, 8 km, at the domed segment center and decreases in thickness toward both segment ends. However, thicker crust is formed in the direction of ridge propagation, suggesting that melt is preferentially transferred toward the propagating ridge tip. Further, while seismic layer 2 remains constant along axis, seismic layer 3 shows profound changes in thickness, governing variations in total crustal thickness. This feature supports mantle upwelling at the segment center. Thus, fluid basaltic melt is redistributed easily laterally, while more viscose gabbroic melt tends to crystallize and accrete nearer to the locus of melt supply. The onset of propagation seems to have coincided with the formation of thicker crust, suggesting that propagation initiation might be due to changes in the melt supply. After a rapid initiation a continuous process of propagation was established. The propagation rate seems to be controlled by the amount of magma that reaches the segment ends. The strength of upwelling may govern the evolution of ridge segments and hence ultimately controls the propagation length. Copyright 2011 by the American Geophysical Union.},
	keywords = {Crustal structure, mid-ocean ridges, ridge propagation, seismic traveltime tomography},
	issn = {15252027},
	doi = {10.1029/2011GC003534},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-79960696393\&partnerID=tZOtx3y1},
	author = {Dannowski, A. and Grevemeyer, I. and Phipps Morgan, J. and Ranero, C. R. and Maia, M. and Klein, G.}
}
@article {PhippsMorgan2008,
	title = {{Intra-arc extension in Central America: Links between plate motions, tectonics, volcanism, and geochemistry}},
	journal = {Earth and Planetary Science Letters},
	volume = {272},
	number = {1-2},
	year = {2008},
	pages = {365{\textendash}371},
	abstract = {This study revisits the kinematics and tectonics of Central America subduction, synthesizing observations of marine bathymetry, high-resolution land topography, current plate motions, and the recent seismotectonic and magmatic history in this region. The inferred tectonic history implies that the Guatemala-El Salvador and Nicaraguan segments of this volcanic arc have been a region of significant arc tectonic extension; extension arising from the interplay between subduction roll-back of the Cocos Plate and the \~{} 10-15mm/yr slower westward drift of the Caribbean plate relative to the North American Plate. The ages of belts of magmatic rocks paralleling both sides of the current Nicaraguan arc are consistent with long-term arc-normal extension in Nicaragua at the rate of \~{} 5-10mm/yr, in agreement with rates predicted by plate kinematics. Significant arc-normal extension can {\textquoteright}hide{\textquoteright} a very large intrusive arc-magma flux; we suggest that Nicaragua is, in fact, the most magmatically robust section of the Central American arc, and that the volume of intrusive volcanism here has been previously greatly underestimated. Yet, this flux is hidden by the persistent extension and sediment infill of the rifting basin in which the current arc sits. Observed geochemical differences between the Nicaraguan arc and its neighbors which suggest that Nicaragua has a higher rate of arc-magmatism are consistent with this interpretation. Smaller-amplitude, but similar systematic geochemical correlations between arc-chemistry and arc-extension in Guatemala show the same pattern as the even larger variations between the Nicaragua arc and its neighbors. {\textcopyright} 2008 Elsevier B.V. All rights reserved.},
	keywords = {arc geochemistry, Central America, extension, magmatism, Plate Tectonics},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2008.05.004},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-47749095517\&partnerID=tZOtx3y1},
	author = {Phipps Morgan, J. and Ranero, C.R. and Vannucchi, P.}
}
