Evolution of abyssal lavas along propagating segments of the Galapagos spreading center

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

113

Scientific paper

The unusual petrological diversity of abyssal lavas erupted along some segments of the Galapagos spreading center is a direct consequence of the propagation (elongation) of these segments into older oceanic crust. With increasing distance behind propagating rift tips, relatively unfractionated MORB erupted close to the tips are joined first by FeTi basalts (bimodal assemblage) and then by a wide range of basaltic and siliceous lavas. Further behind propagating rift tips, this broad range diminishes again, approaching the narrow compositional range of adjacent normal ridge segments.
These compositional variations reflect the evolution of the subaxial magmatic system beneath the newly forming spreading center as it propagates through a pre-existing plate. We envisage this evolution as proceeding from small, isolated, ephemeral magma chambers through increasing numbers of larger, increasingly interconnected chambers to the steady-state buffered system of a normal ridge. Throughout this evolution, magma supply rates gradually increase and cooling rates of crustal magma bodies decrease. High degrees of crystal fractionation are favored only when a delicate balance between cooling rate and resupply rate of primitive magma is achieved.
At other propagating and non-propagating ridge-transform intersections the degree to which the balance is achieved and the length of ridge over which it evolves control the distribution of fractionated lavas. These effects may be evaluated provided a number of tectonic variables including transform length, spreading and propagation rates are taken into account.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Evolution of abyssal lavas along propagating segments of the Galapagos spreading center does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Evolution of abyssal lavas along propagating segments of the Galapagos spreading center, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Evolution of abyssal lavas along propagating segments of the Galapagos spreading center will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1262671

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.