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Zircon geochronological and geochemical insights into pluton building and volcanic-hypabyssal-plutonic connections: Oki-Dōzen, Sea of Japan - a complex intraplate alkaline volcanoThe relationship between plutonic and volcanic components of magmatic plumbing systems continues to be a question of intense debate. The Oki-Dōzen Islands, Sea of Japan, preserve outcrops of temporally-associated plutonic, hypabyssal and volcanic rocks. Juxtaposition of these, by post-intrusion uplift, placed Miocene syenites in inferred faulted contact with volcanic trachytes that are cut by rhyolite hypabyssal dikes. This provides a window deep into the timing and origins of magma storage architecture and dynamics. Our aim is to determine what the age and composition of zircon, which is ubiquitous in all samples, can reveal about the plutonic-volcanic connection. Here we show magma source characteristics are recorded in zircon Hf isotopes whereas, in addition to source composition, differentiation processes - assimilation of heterogeneous hydrothermally altered crust and extensive fractional crystallization - are preserved in zircon O isotopes and trace elements, respectively. Combined with new U-Th-Pb SHRIMP zircon ages, 6.4–5.7 Ma, the compositional data show pluton formation was by protracted amalgamation of discrete magma pulses. The rhyolite dike preserves an evolved fraction segregated from these. Synchronous with plutonism was volcanic eruption of trachyte magma derived from the same source, but apparently stalled at a relatively shallow depth. Stalling occurred at least above the zone of amphibole stability since amphibole-compatible Sc and Ti were not depleted in the trachyte melt - resulting in elevated values of these in the volcanic, compared to the plutonic, zircon. Identifying smaller episodic magma pulses in a larger magmatic complex places constraints on potential magma fluxes and eruptible volumes. Distinct from high-flux, large volume, plume-related ocean islands with extensive vertically distributed multi-stage magmatic reservoirs or subduction-related transcrustal magma reservoirs, Oki-Dōzen was a low-flux system with incremental pluton growth and small- to moderate-scale eruptions.
The zoo of the giraffe women: a journey among the Kayan of Northern ThailandIn a village in the far north of Thailand, under the stunning light of a tropical sun, surreal women impeccably wearing their ethnic attire, smiling and motionless, offer themselves to the cameras of voracious tourists. Adorned with gorgeous necklaces of shining brass coils, they are the famous “giraffe women”, the epithet commonly used to define members of the Kayan tribe originally from eastern Burma. The vivid contrast between the myths narrating the origin of this ethnic group and their current condition as refugees from the civil war in their homeland provides an outstanding and sharp testimony to life in Thailand’s “human zoos”. A wide selection of photographs taken by the author using primitive vintage cameras from the early 1900s and a poignant short video, shot with Super-8 film, enrich the volume, visually amplifying the unique mood of the written account.
UntitledAnthropometric data are often described in terms of percentiles and too often digital human models are synthesised from such data using a single percentile value for all body dimensions. The poor correlation between body dimensions means that products may be evaluated against models of humans that do not exist. Alternative digital approaches try to minimise this difficulty using pre-defined families of manikins to represent human diversity, whereas in the real world carefully selected real people take part in ‘fitting trials’. HADRIAN is a digital human modeling system which uses discrete data sets for individuals rather than statistical populations. A task description language is used to execute the evaluative capabilities of the underlying SAMMIE human modelling system as though a ‘real’ fitting trial was being conducted. The approach is described with a focus on the elderly and disabled and their potential exclusion from public transport systems.