Hawaiian volcanics

Figure 1.147. Jackson s curve and arc stress reorientations. Apparent swing motion of Pacific Plate (Jackson et al., 1975) and regional stress orientation at the Northeast Honshu convergent margin are illustrated in order to show their synchronous relationship. Dashed line represents the average trend of the Hawaiian volcanic chain. Pacific plate moves along the direction with fluctuation in reference to Hawaii Hot Spot. Vertically shaded parts of the graph indicate the climax phases of clockwise episodes . Lower part of the figure shows the phases and reversals in orientation of tectonic stress fields on the inner zone of Northeast Honshu Arc (Takeuchi, 1987).

Ribe NM, Christensen UR (1999) The dynamical origin of Hawaiian volcanism. Earth Planet Sci Lett 171 517-531... 

Vigier N, Bourdon B, Joron J-L, Allegre CJ (1999) U-Th-Ra disequilibria in Ardoukoba tholeiitic basalts (Asal rift) timescales of ciystallization. Earth Planet Sci Lett 174 81-98 Watson S, McKenzie D (1991) Melt generation by plumes a study of Hawaiian volcanism. J Petrol 32 501-537... 

Watson, S. McKenzie, D. 1991. Melt generation by plumes a study of Hawaiian volcanism. Journal of Geophysical Research, 83, 5989-6004. 

Island volcanics from oceanic ridges and rises have lead isotope ratios (references in Table 17 data on Fig. 18 with selected data on Table 18) which are in general more radiogenic than those of abyssal basalts and Hawaiian volcanics (Doe, 1968a). This relationship is... 

Pacific Ocean basin Abyssal basalts (Fig. 18-20) Hawaiian volcanics (Fig. 18 — 20)... 

Soils are complex systems that require thorough examination in order to place data in a meaningful framework. For instance, Hawaiian soils from areas with essentially identical young basaltic bedrock and similar annual rainfall have been examined (Huh et al. 2002 Pistiner and Henderson 2003), but results are strikingly different. Huh et al. (2002) reported finding a 2x to 6x increase in Li concentration relative to rmweathered basalt and variations in 5 Li between +3 and +10 from lower to upper soil horizons. Pistiner and Henderson (2003) examined nine successive layers of volcanic soil that showed restricted variability in both... 

As shown in Figure 19.6, vent fields have been confirmed (or inferred) across depths ranging from 200 to 4300 m, with the most lying between 2200 and 2800 m. Very shallow systems are associated with volcanism that has built oceanic crust above sea level, such as near Iceland, the Hawaiian Islands, and the Azores. 

Figure 6.2 Primary minerals containing Fe (e.g., pyroxenes and amphiboles in basaltic volcanic rocks) are weathered, releasing Fe into solution, which is then precipitated and accumulated in oxides as illustrated when examining the composition and percentage of clay and free oxides in Hawaiian soils. (Modified from Sherman, 1952.)...

Yang H. J., Frey F. A., and Clague D. A. (2003) Constraints on the source components of lavas forming the Hawaiian north arch and honolulu volcanics. J. Petrol. 44, 603-627. 

Winner W. E. and Mooney H. A. (1980) Responses of Hawaiian plants to volcanic sulfur dioxide stomatal behavior and foliar injury. Science 210, 789-791. Zdanowicz C. M., Zielinski G. A., and Germani M. S. (1999) Mt. Mazama eruption calendrical age verified and atmospheric impact assessed. Geology 27, 621-624. 

One unique ecosystem that has yielded an unparalleled natural laboratory for the study of soil and terrestrial ecosystem development in general, and the evolution of phosphorus and other nutrient bioavailability in particular, is the Hawaiian Island chain in the central subtropical Pacific Ocean (Vitousek et al., 1997). These volcanic islands aU have a soil substrate of basaltic rock with an essentially identical initial chemistry, are similar in climate, and are arrayed along an age transect from young, active volcanoes in the southeast to the oldest islands in the northwest. This system thus offers the opportunity for contemporaneous study of soil and ecosystem development processes that have occurred on thousand-year timescales, by comparing soil chemistry, nutrient availability, and ecosystem development on each of the islands, which range in age from 0.3 kyr to 4,100 kyr (Vitousek et al., 1997). 

Volcanoes are responsible for creating several built-out coasts. In some parts of the ocean, the eruption of undersea volcanoes erected mountains of lava that eventually reached the water s surface and formed islands. As these mountains grew, their coastlines were dominated by lava flows. The Hawaiian Islands were formed from volcanic activity. 

Naughton, J. J., and K. Terada (1954). Effect of eruption of Hawaiian volcanoes on the composition and carbon isotope content of associated volcanic and fumarolic gases. Science 120, 580-581. 

There are many environments in which oxygen isotope variations are dominated by crustal contamination. Clear examples include convergent-margin volcanic centers erupted through thick and/or sediment-rich crust, continental intra-plate magmas, central volcano complexes on Iceland, and evolved, 0-enriched lavas from the Canary islands. Controversial cases that have also been argued to reflect crustal contamination are subtly 0-depleted Hawaiian and Icelandic basalts. 

Hofmann AW (1997) Mantle geochemistry The message from oceanic volcanism. Nature 385 219-229 Honda M, McDougall I, Patterson DB, Donlgeris A, Clagne DA (1991) Possible solar noble-gas component in Hawaiian basalts. Natnre 349 149-151... 

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