The SWEAT Hypothesis

The study of the structure and tectonic evolution of Antarctica was stimulated by a proposal that the East Antarctic craton was originally connected to North America (Moores 1991 Dalziel 1991 Hoffman 1991). This startling hypothesis was preceded by reports of Hartnady (1986,1991) and was prompted by the work of the Bell and Jefferson (1987) who had previously correlated the late Precambrian rocks of western Canada with similar rocks in South Australia. These authors concluded that a rift had formed between western Canada and Australia at about 1,200 Ma and that both continental fragments had developed complementary passive rift margins by about 750 Ma. 

The re-alignment of East Antarctica, Australia, India, and Noth America proposed by the SWEAT hypothesis 

Another interesting consequence of the SWEAT reconstruction is that the Yavapai-Mazatzal orogenic 

) The fragmentation of Gondwana to form the southern continents was accompanied by large-scale eruption of basalt and the intrusion of diabase sills not only along the Ross orogen of Antarctica (i.e., the Ferrar Dolerite) but also in South Africa, in Brazil, in northwest Africa, and in North America (Faure 2001). 

---

Fig. 9.5 Coats Land is located along the east coast of the Weddell Sea in East Antarctica. It consists of a low ice-covered ridge about 580 km in length north of the FUchner Ice Shelf. The only rock outcrops in Coats Land are the Littlewood, Bertrab, and Moltke nunataks (B, L, M) aU of which are inaccessible and have been rarely visited by geologists. These nunataks are composed of rhyohte and granophyre which crystaUized at 1,076 7 Ma (Storey et al. 1994). This date as well as other age determinations in Table 9.1 confirm that these nunataks lie within the belt of Grenville-age rocks of the East Antarctic craton in agreement with the SWEAT hypothesis of Moore (1991) (Adapted from Anonymous 1990)...

The SWEAT hypothesis of Moores (1991) also positions the Haag Nunatak, which is presently located close to the crustal block of the Ellsworth-Whitmore Mountains (Section 8.1.3), within the Grenville belt in the gap between Coats Land and the Yavapai-Mazatzal province of North America in Fig. 9.6. In this way, the Haag Nunatak has found a home that is consistent with... 

Additional support for the SWEAT hypothesis has come from new age determinations published by Storey et al. (1994), Gose et al. (1994, 1997), and... 

Ricci CA (ed) (1997) The Antactic region geological evolution and processes. Terra Antartica Siena, Italy Siever R (1983) The dynamic earth. Sci Am 249(3) 46-55 Smith GA (1992) Plate tectonics and continental drift. In Brown GC, Hawkesworth CJ, Wilson RCL (eds) Understanding the earth. Cambridge University Press, Cambridge, pp 187-203 Storey BC, Pankhurst RJ, Johnson AC (1994) The Grenville Province within Antarctica a test of the SWEAT hypothesis. J Geol Soc London 151 1-4... 

No studies were located regarding aluminum absorption in humans after dermal exposure to aluminum or its compounds. Aluminum compounds are common additives in underarm antiperspirants. The active ingredient is usually an aluminum chlorhydrate salt, which is thought to form an obstructive plug of aluminum hydroxide within the sweat duct (Reiber et al. 1995). The possibility that aluminum in antiperspirants may be absorbed directly through the skin has been suggested (Graves et al. 1990), but this hypothesis has not been clinically confirmed. 

Since cavitational effects in fluids vary inversely with ultrasound frequency, it is likely that cavitational effects should play an even more important role in low-frequency sonophoresis. Tachibana et al. hypothesized that application of low-frequency ultrasound results into acoustic streaming in the hair follicles and sweat ducts of the skin, thus leading to enhanced transdermal transport. Mitragotri et al. hypohesized that transdermal transport during low-frequency sonophoresis occurs across the keratinocytes rather than hair follicles. They provided the following hypothesis for the higher efficacy of low-frequency sonophoresis. 

Tessensohn F (1997) Shackleton Range, Ross orogen and SWEAT hypothesis. In Ricci CA (ed) The Antarctic Region Geological evolution and processes. Proceedings of the seventh international symposium on Antarctic Science, Terra Antrutica, Siena, Italy, pp 5-12... 

Dermal. Renshaw reported that >80% of SM applied to the skin evaporates if the application site is left unoccluded, and the rate of penetration of SM into human skin was 1-4 g cm min from unspecified contamination densities. Some authors claim that in humans the absorption is via the sweat glands, but there is no empirical evidence to support this hypothesis for SM. 

Moores EM (1991) Southwest U.S.-East Antarctic (SWEAT) connection A hypothesis. Geol 19 425-428 Mortimer G (1981) Provisional report on the geology of the basement complex between Miers rmd Seilmon Valley McMurdo Sound, Antarctica New Zeeiland Antarctic Record 3(2) 1-8... 

---