![]() Erebus offers a unique opportunity to investigate magmatic system processes from the mantle source to the surface and the enigmatic tectonic-structural controls of extensional magmatism and volatile release. However, they also provide important resources such as rare earth elements and precious metals and thus are important to understand 6, 7. Phonolite magmas in other settings have been explosively destructive 5. Compositionally uniform phonolitic lavas have dominated Erebus volcano eruptions for the last 17 ka 4 (Fig. Mount Erebus is the only phonolitic volcano with a persistent summit lava lake 3. Phonolitic-series magma is alkali-rich and highly evolved from its parental basanite. ![]() Rift settings and alkalic magmas contribute enormous amounts of CO 2 to the global exosphere budget, with climate-forcing level increases of atmospheric concentrations documented several times during Earth’s history 2. Basaltic alkalic magmas are CO 2-rich because they result from low degrees of partial melting of a mantle source often showing signs of being complexly metasomatized 1. Arc magmas typically have volatiles dominated by H 2O from dehydration of subducted oceanic crust. Unlike H 2O-rich subduction arc volcanoes, CO 2-dominated Erebus geophysically shows continuous magmatic structure to shallow crustal depths of < 1 km, as the melt does not experience decompression-related volatile supersaturation and viscous stalling.Īlkalic volcanoes in rift settings stand in stark contrast to calc-alkaline volcanoes in arcs, such as the ring of fire around the Pacific Ocean. This magmatic valve lies within an inferred, east-west structural trend forming part of an accommodation zone across the southern termination of the Terror Rift, providing a dilatant magma pathway. The lateral turn represents a structural fault-valve controlling episodic flow of magma and CO 2 vapour, which replenish and heat the high level phonolite differentiation zone. Here we show using magnetotelluric data that a steep, melt-related conduit of low electrical resistivity originating in the upper mantle undergoes pronounced lateral re-orientation in the deep crust before reaching shallower magmatic storage and the summit lava lake. Seismic studies provide limited images of the magmatic system. Erebus volcano, Antarctica, with its persistent phonolite lava lake, is a classic example of an evolved, CO 2-rich rift volcano. More information about ASTER is available at. The Terra mission is part of NASA's Science Mission Directorate, Washington, D.C. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Example applications are: monitoring glacial advances and retreats monitoring potentially active volcanoes identifying crop stress determining cloud morphology and physical properties wetlands evaluation thermal pollution monitoring coral reef degradation surface temperature mapping of soils and geology and measuring surface heat balance. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products. The instrument was built by Japan's Ministry of Economy, Trade and Industry. ASTER is one of five Earth-observing instruments launched Dec. With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. The image was acquired December 31, 2013, covers an area of 63 x 73 km, and is located at 77.5 degrees south, 167.1 degrees east. Continuous lava-lake activity with minor explosions, punctuated by occasional larger strombolian explosions that eject bombs onto the crater rim, has been documented since 1972, but has probably been occurring for much of the volcano's recent history. The glacier-covered volcano was erupting when first sighted by Captain James Ross in 1841. An elliptical 500 x 600 m wide, 110-m-deep crater truncates the summit and contains an active lava lake within a 250-m-wide, 100-m-deep inner crater. The 3794-m-high Erebus is the largest of three major volcanoes forming the crudely triangular Ross Island. Mount Erebus, the world's southernmost historically active volcano, overlooks the McMurdo research station on Ross Island.
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