Benioff zone

In detail, some of the trends within individual across-arc traverses are complicated. For example, within Kamchatka U/Th ratio increases with depth to the Benioff zone (Turner et al. 1998), although there is no simple correlation with (Fig. 20a). 

Kesson S. E. and Ringwood A. E. (1989) Slab-mantle interactions 1. Sheared and refertilized garnet peridotite xenoliths-samples of wadati-benioff zones Chem. Geol. 78, 89-96. 

In another mechanism of solid transfer across the Benioff zone, imbrication of the subduction thrust at shallow depth, or downward migration of the subduction shear zone at greater depth, may transfer material from the top of the downgoing... 

Mitchell A. H. G. and Garson M. S. Relationship of porphyry copper and circum-Pacific tin deposits to palaeo-Benioff zones. Trans. Instn Min. Metall. (Sect. B Appl. earth sci.), 81, 1972, BlO-25. 

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