Aller

Die C—S-Bindung verschiedener Organo-schwefel-Verbindungen kann elektroche-misch gespalten werdcn (zur Reduktion am Schwefel-Atom unter Erhalt aller C-S-Bin-dungen s. S. 680. 

MacKenzie and Garrels equilibrium models. Most marine clays appear to be detrital and derived from the continents by river or atmospheric transport. Authigenic phases (formed in place) are found in marine sediments (e.g. Michalopoulos and Aller, 1995), however, they are nowhere near abundant enough to satisfy the requirements of the river balance. For example, Kastner (1974) calculated that less than 1% of the Na and 2% of the K transported by rivers is taken up by authigenic feldspars. 

Michalopoulos, P. and Aller, R. C. (1995). Rapid clay mineral formation in Amazon Delta sediments reverse weathering and oceanic elemental cycles. Science 270, 614-617. 

Pumphrey RSH, Gowland MH Further fatal aller- 30 gic reactions to food in the United Kingdom, 1999-2006. J Allergy Clin Immunol 2007 119 1018-1019. 

Aller E, Buck RT, Drysdale MJ, Ferris L, Haigh D, Moody CJ, Pearson ND, Sanghera JB (1996) J Chem Soc Perkin Trans 1 2879... 

Filter pack. Filter pack is the term used to describe the materials placed in the annular space between the screen and the formation (Figure 1). Aller et al. and Driscoll provide a discussion of the purpose and selection of filter pack materials. The filter pack serves a number of important mechanical functions. During well construction, it helps to keep the well screen centered in the borehole and acts to block the sealant from entering the well screen. The filter pack also improves hydraulic conductivity between the well screen and the formation, prevents formation materials from migrating to the well screen by acting as a filter, and helps support the screen and borehole. ... 

Measurements of " Th in sediment samples (Aller and Cochran 1976 Cochran and Aller 1979) used much the same approach as outlined above. In this case, the dried sediment sample ( 10 g) was leached with strong mineral acid (HCl) in the presence of a yield monitor (generally Th, an artificial Th isotope resulting from the decay of Th that is produced by neutron capture on Th). Thorium was separated from U and purified by ion exchange chromatography, and electrodeposited onto stainless steel planchets. Counting and determination of " Th activity followed the procedure outlined above. 

Figure 7. Excess activity versus depth (left) and X-radiograph (right) in a sediment core collected from the New York Bight, showing the importance of mixing by benthic fauna in the upper part of the seabed. Abundant individnals of the small bivalve Nucula proximo may be seen in the X-radiograph near the sediment-water interface, and the light-colored areas represent bnrrows of Nephtys sp. and Ceriantheopsis sp. Reprinted from Estuarine Coastal and Shelf Science (formerly Estuarine and Coastal Marine Science) Vol. 9, Cochran and Aller, pp. 739-747, 1979, with permission from Elsevier Science.

Values of Db determined by " Th profiles commonly range from 1 to 50 cm7y in estuarine and slope sediments (Aller and Cochran 1976 Aller et al. 1980 Sun et al. 1994 Gerino et al. 1998 Green et al. 2002) to < 10 cm7y in the deep sea (Aller and DeMaster 1984 Pope et al. 1996). Although there is some overlap, mixing rates in the deep sea tend to be lower than those in nearshore sediments. This trend has been documented with °Pb profiles as well (e.g., Henderson et al. 1999). 

Aller RC, Cochran JK (1976) Th-234/U-238 disequilibrium in nearshore sediments particle reworking and diagenetic time scales. Earth Planet Sci 29 37-50... 

Aller RC, Benninger LJ, Cochran JK (1980) Tracking particle associated processes in nearshore environments by use of disequilibrium. Earth Planet Sci Lett 47 161-175... 

Aller RC, DeMaster DJ (1984) Estimates of particle-flux and reworking at the deep-sea floor using Th-234/U-238 disequilibrinm. Earth Planet Sci Lett 67 308-318 Amid D, Cochran JK, Hirschberg DJ (2002) disequihbrium as an indicator of the seasonal... 

Cochran JK Aller RC (1979) Particle reworking in sediments from the New York Bight apex evidence from disequilibrium. Estuar Coast Mar S 9 739-747... 

Green MA. Aller RC, Cochran JK, Lee C, Aller JY (2002). Bioturbation in shelf/slope sediments off Cape Hatteras, North Carolina The use of " Th, Chl-a, and Br to evaluate rates of particle and solute transport. Deep-Sea Res 1149(20) 4627-4644... 

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