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What are the differences between N-MORB, E-MORB and OIB with regards to: Tectonic setting Geochemical features There are several types of basalts, but I can't find a clearly explained article.
PDF | On Aug 1, 2006, A. W. Hofmann and others published The origin of E-MORB | Find, read and cite all the research you need on ResearchGate
Complementary trace element modeling yielded compositionally similar E-MORB and OIB sources with moderately incompatible element enrichments in the OIB source due to the influence of recycled oceanic crust (Prytulak & Elliott, 2007).
E-MORBs were first noted near mantle plumes so that enrichment of highly incompatible elements was initially understood in terms of infiltration of plume-related melts into the MORB plumbing system (4), but subsequent work found some E-MORBs far from plumes (5).
N-MORB, E-MORB, and OIB are like geochemical fingerprints, each pointing to a different source within the Earth's mantle. N-MORB tells us about the depleted upper mantle, E-MORB hints at recycled materials and shallower plumes, and OIB screams of deep mantle origins and ancient ingredients.
ALL MORB and N-MORB are substantially more enriched than early estimates of normal ridge basalts. The mean composition of back-arc spreading centers requires higher extents of melting and greater concentrations of fluid-mobile elements, reflecting the influence of water on back-arc petrogenesis.
This calls for a reevaluation of E-MORB origin separate from injection of deep plumes into the upper mantle. Taking into account trace-element and radiogenic isotope systematics of N- and E-MORB, we evaluate implications for average ages of upper mantle heterogeneity and rates of formation and destruction of E-MORB sources.
These E-MORB subsequently spread away from the AST, and, finally, were preserved on the seafloor through asymmetric construction of the extrusive layer.
Collections of mid-ocean ridge basalts (MORB) do not represent a perfectly random sampling of the mid-ocean ridge system. Thus, a bias is introduced into characterizations of the global MORB reservoir, and by inference geochemical models of the Depleted MORB Mantle (DMM) and the bulk silicate Earth (BSE), based on measurements of these samples. Of particular importance and a subject of ongoing ...
Of particular importance and a subject of ongoing debate is the ubiquity of ``enriched-type'' samples, or E-MORB, which represent a subordinate component of global MORB and are 5 - 10× more ...