HR: 1330h
AN: V13B-02    [Abstracts]
TI: The Core as the Third Pivotal End Member of the Earth's Plate Tectonic Cycle: A New Theory
AU: * Carman, J H
EM: jhcarman@cfl.rr.com
AF: Care-Man Enterprises, 518 Pennsylvania Av, Saint Cloud, FL 34769 United States
AB: Existing data and use of a hypothetical model, post-Stishovite-Magnesiowustite-Iron, indicate that the Earth's core could be the the convertor end member of the Earth's Plate Tectonic Cycle (EPTC): a new theory. This third pivitol end member, the core, is the place where the cycle begins and ends, to begin again. The first pivotal end member of the EPTC, for a three end member system, is the global MORB end member where new oceanic crust and lithosphere are created. Sea-floor spreading connects it to the second end member, the subduction end member, where oceanic crust and lithosphere disappear to become cold lithospheric-crust complexes descending through the mantle toward the Earth's core. When complexes break into it they are slowed, turned and endothermally ingested. Partial melting frees lower mantle phases and iron while forming metallic liquid and a densified immiscible silicate liquid, of which 17 vol.% reduces the bulk density of a convecting outer core by 10 %. Freed crystalline phases form micro-phases of micrometer to millimeter in size that more or less fill mega-bodies of <83 vol.% metallic liquid and <17 vol.% immiscible silicate liquid, both of centimeters to kilometers in size. Excess core energy starting each cycle comes mainly from irreversible exothermal reactions at numerous unstable phase contacts by stable phases within and between mega-bodies to yield stable products of lower Gibbs free energy, only to make new contacts and react...and react again. Other sources of exothermal energy come from radioactive silicate liquid and friction at stable phase contacts during mega-body convection. Heat accumulated from these energy sources tends to expand the outer core as univariant boundary reactions of the core and the lower mantle reverse, with +5.0 cm³g^-1comming from the inner core boundary reaction alone. The outer core's pervasive expansion against the passively resisting strength of the mantle results in explosive ejection of silicate liquid along a line of weakness or at a point of weakness of the CMB when it fails, as it must. Superheated actions of this liquid with lower mantle phases result in hybrid, hot and solid domains that ascent as hot basic plumes in a cooler and denser ultrabasic mantle. Decompression melting of the plume above 290 km contributes new basalt crust at mid-oceanic ridges, the MORB end member, from a line source of the CMB. New crust for oceanic islands basalts arrives there, after similar processes yield plumes from point sources of the CMB. Both of these basalt types are thought to be linked with silicate liquid ejected fron the Earth's outer core as expressed by the ubiquitous and unexplained C-component of Pb isotope ratios of Atlantic-, Indian- and Pacific mid-oceanic basalts, major segments of the MORB end member of the EPTC, and by its corresponding FOZO isotope component of oceanic island basalts. Oceanic crust and lithosphere disappear at the subduction end member before it is a twenty-third the age of the Earth, and leads to its ingestion and eventual energization in the Earth's outer core, the convertor, and third end member of the EPTC, to drive ensuing cycles. It seems unavoidable that egress features for silicate liquid on the CMB could serve as a template for the EPTC in a bottom-up dynamic, except for the actions of the subduction end member of the EPTC. There is no shortage of silicate liquid in the outer core as 17 vol.% is almost twice the volume of the entire crust of the Earth. Finally, it seems possible that some of the unexplained heat flux of the Earth, over and above the radioactivity of the mantle, may be attributed to this new paradigm that drives the Earth's Plate Tectonic Cycle.
UR: http://www.EarthsPlateTectonicCycle.us
DE: 1015 Composition of the core
DE: 1030 Geochemical cycles (0330)
DE: 1213 Earth's interior--dynamics (8115, 8120)
DE: 8115 Core processes (1507)
DE: 8125 Evolution of the Earth
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2005 Joint Assembly