Results 131 to 140 of about 3,414 (186)
Some of the next articles are maybe not open access.
The Process of Formation of Ocean Crust
Science, 1983Ocean crust is the outermost layer of earth under the oceans. It is separated from the underlying mantle by a seismic transition zone called the Moho. A widely held view is that the Moho represents a petrologic change from basaltic-type rocks to a mantle composed mostly of olivine and pyroxene.
openaire +2 more sources
The oceanic crust as a bioreactor
2004Various lines of evidence suggest that large portions of hydrothermal systems in the oceanic crust acts like a giant bioreactor that mediates water-rock exchange and buffers the chemical composition of seawater. We review the current literature and present new chemical, biological and petrographic data on microbially mediated alteration of glass in the
Hubert Staudigel +6 more
openaire +1 more source
1993
The mantle contains 84% of the volume and 68% of the mass of the Earth, but because it is separated from direct observation by the thin crust — only about 6 km thick beneath the oceans and an average of 35 km beneath the continental surface — there are many unsolved problems.
G. C. Brown, A. E. Mussett
openaire +1 more source
The mantle contains 84% of the volume and 68% of the mass of the Earth, but because it is separated from direct observation by the thin crust — only about 6 km thick beneath the oceans and an average of 35 km beneath the continental surface — there are many unsolved problems.
G. C. Brown, A. E. Mussett
openaire +1 more source
AAPG Bulletin, 1979
The model presented is based on the interpretation of marine geophysical data, studies of dredged rocks, theoretical modeling, geologic investigations of ophiolite complexes on the continents, and results of deep-sea crustal drilling by JOIDES/IPOD. Along the axis of the midoceanic ridge system a zone of upwelling asthenosphere extends from the base of
openaire +1 more source
The model presented is based on the interpretation of marine geophysical data, studies of dredged rocks, theoretical modeling, geologic investigations of ophiolite complexes on the continents, and results of deep-sea crustal drilling by JOIDES/IPOD. Along the axis of the midoceanic ridge system a zone of upwelling asthenosphere extends from the base of
openaire +1 more source
Evidence for Crust in the Deep Ocean derived from Continental Crust
Nature, 1971FIG. 1 shows the profile of a free-air gravity anomaly obtained by HMS Hecate in the Bay of Biscay in 1967 (with two gravi-meters back-to-back to eliminate cross-coupling error). The track is shown in Fig. 2 together with the available deep-water refraction stations; D12 was shot by Ewing and Ewing1 and A by RRS Discovery in 1968 (R. B.
M, Bacon, F, Gray
openaire +2 more sources
2014
Magma generated by decompression melting of the upwelling mantle beneath mid-ocean ridges (MORs) rises buoyantly and accumulates in crustal magma chambers (e.g., Forsyth, 1992). The long-held view is that oceanic crust is built from in situ crystallization of melts in these reservoirs, as well as from melts extracted from the magma chamber(s) in the ...
openaire +1 more source
Magma generated by decompression melting of the upwelling mantle beneath mid-ocean ridges (MORs) rises buoyantly and accumulates in crustal magma chambers (e.g., Forsyth, 1992). The long-held view is that oceanic crust is built from in situ crystallization of melts in these reservoirs, as well as from melts extracted from the magma chamber(s) in the ...
openaire +1 more source
Magnetization of the oceanic crust
Reviews of Geophysics, 1979The Vine‐Matthews [1963] model of the magnetic structure of the igneous oceanic crust, in which basement is considered to be made up of alternating normal and reverse magnetic polarity blocks with a one‐to‐one match with linear marine magnetic anomalies, has received wide acceptance in the geological and geophysical community. Comparison of the results
openaire +1 more source
1991
In this chapter studies on Indian Ocean abyssal basalts are used as a vehicle to discuss magmatic lineages and melting processes, largely derived from detailed petrographic observations and mineral chemistry. The mineralogical aspects and the magmatic processes envisaged can be considered as adjunct topics to Chapters 5 and 7, respectively, in Part II.
openaire +1 more source
In this chapter studies on Indian Ocean abyssal basalts are used as a vehicle to discuss magmatic lineages and melting processes, largely derived from detailed petrographic observations and mineral chemistry. The mineralogical aspects and the magmatic processes envisaged can be considered as adjunct topics to Chapters 5 and 7, respectively, in Part II.
openaire +1 more source
1991
The Pacific Ocean basin comprises about one third of the earth’s surface, or 49.8% by area of our planet’s oceans and seas. It includes the earth’s largest and fastest moving plate, the Pacific plate, in addition to the smaller Nazca, Cocos, Rivera, Juan de Fuca, Gorda and Explorer plates, three so-called microplates (Galapagos, Easter and Juan ...
openaire +1 more source
The Pacific Ocean basin comprises about one third of the earth’s surface, or 49.8% by area of our planet’s oceans and seas. It includes the earth’s largest and fastest moving plate, the Pacific plate, in addition to the smaller Nazca, Cocos, Rivera, Juan de Fuca, Gorda and Explorer plates, three so-called microplates (Galapagos, Easter and Juan ...
openaire +1 more source
1989
Significant differences between ophiolites (table 8.1) led us to distinguish a harzburgite ophiolite type (HOT) and a lherzolite ophiolite type (LOT) which were ascribed respectively to fast and slow spreading situations (chapter 8). Similarly, significant differences between fast and slow spreading ridges encourage comparisons with these two types of ...
openaire +1 more source
Significant differences between ophiolites (table 8.1) led us to distinguish a harzburgite ophiolite type (HOT) and a lherzolite ophiolite type (LOT) which were ascribed respectively to fast and slow spreading situations (chapter 8). Similarly, significant differences between fast and slow spreading ridges encourage comparisons with these two types of ...
openaire +1 more source