Sepiolite and Palygorskite in Japan

A New Approach to Compositional Limits for Sepiolite and Palygorskite

“…Japan (Imai et al, (1969) Bakkasetter, Shetland Isles, Scotland (Stephen, 1954) Tafraout, Morocco (Caill6re andHenin, 1957) Mr. Flinders, Queensland, Australia (Rogers et at., 1954) Eastern Saudi Arabia (Shadfan et al, 1985) Timsanpalli, Deccan, India (Siddiqui, 1984) Mao Kou Limestone, Sichuan province, China (Zheng, 1991) Anhui province, China (Zbeng, 1991) Jiansu province, China (Zheng, 1991) Attapulgus, Georgia, USA (Bradley, 1940) Metaiine Fails, Washington, (Huggins et al, 1962) Jordan Valley, Israel (Wiersma, 1970) Attapulgus, Georgia (Robertson, 1961) Bercimuel, Segovia, Spain (Suarez et al, 1991) Umm Radhuma, Saudi Arabia (Dahab and Jarjarah, 1989) Bercimuel, Segovia (Suarez et al, 1995) Yagca formation, Turkey (Yalqin and Bozkaya, 1995) (Millot et al, 1977) Kizilyalak formation, Turkey (Yal$in and Bozkaya, 1995) Ugurlu formation, Turkey (Yal$in and Bozkaya, 1995) Taodeni, Algeria (Caill6re, 1934b) Bakkasetter, Shetland (Stephen, 1954) Dogniaska, USSR (Fersmann, 1913) Permsk, USSR (Fersmann, 1913) Northwestern Transvaal, South Africa (Botha and Huhes, 1992) Dornboom, South Africa (Heystek andSchmidt, 1953) Padasjoki, Finland (Linqvist andLaitakari, 1981) (1-5) from Newman and Brown (1987); (ll) from Imai and Otsuka (1984); (12) and (13) from Weaver and Pollard (1973); (14) and (27) from Isphording (1984); (19) from Suarez et al (1994); (22-25) from Caill6re and H~nin (1972). lies between 6.95-8.1 1 (average 7.72) for eight holes, or between 2.6-3.02 on the basis of three octahedral positions (one-half unit cell) (T...…”

Varied crystallization conditions for Neogene sepiolite and associated Mg-clays from Madrid Basin (Spain) traced by oxygen and hydrogen isotope geochemistry

“…In some shallow restricted basins with evaporitic conditions, sepiolite, Mg-rich smectites (saponite, stevensite) and kerolite are authigenic, usually together with sulfate, carbonate and salt deposits (Millot, 1964;Chamley, 1989), as can be the case in near-surface carbonate aquifers (Kautz and Parada, 1976). Sepiolite was described occasionally as resulting from interaction of low-temperature hydrothermal solutions in Japan (Imai and Otsuka, 1984) and from hydrothermal alteration of volcanics (Irkec ß and Ü nlü , 1993). It was also observed in veins of Turkish ophiolite complexes (Yeniyol, 1986).…”

Fault-Hosted Palygorskite from the Serrata De Níjar Deformation Zone (SE Spain)

“…As shown by the stability conditions for palygorskite (Imai and Otsuka, 1984), this mineral is stable below a temperature range of 220-27S"C (P '" 24.5 MPa). Above these temperatures, palygorskite transforms into trioctahedral smectite.…”