INGEIS   05370
INSTITUTO DE GEOCRONOLOGIA Y GEOLOGIA ISOTOPICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
DISORDERED NATROLITE OF NEUQUEN, PATAGONIA ARGENTINA
Autor/es:
MARIA ELENA VATTUONE, SABRINA CROSTA, YANINA BERBEGLIA, CARMEN MARTINEZ DOPICO Y ERNESTO GALLEGOS
Lugar:
Santa Fe, New Mexico, EEUU
Reunión:
Congreso; 44th Annual Meeting of the Clay Mineral Society; 2007
Institución organizadora:
Clay Mineral Society
Resumen:
Natrolite has been found in an alkaline zeolite assemblage in an amygdaloid basalt in Junín de los Andes, Neuquén province, Argentina, as noted Vattuone et al. (2005).  Following Gaines et al. (1997) and Deer, et al. (2004), the degree of ordering in the structure of natrolite is estimated using the difference between the b and a unit cell dimensions. In “fully ordered” natrolite b-a = 0.35 Å, and in the disordered type, “sodic rich gonnardite (ex tetranatrolite)”  b-a = 0 Å  (completly disordered type) to 0.175 Å (50% disorder). XRD analysis were performed, using the Debye Scherrer method, obtained with a goniometer, 1,5418 Å Cu Kα and a Ni filter. The XRD data of the natrolite samples analyzed (JU1-4 and  JU1-7N)   correspond to the 20-0759 and 19-1185 files of  JCPDS, of the Mineral Powder Diffraction Fill Data Book (Bayliss et al. 1986). Based on this, the cell parameters were calculated for each sample (table 1) and b-a = 0.232 (JU1-4) and 0.183 (JU1-7N). In according  to this,  Junin natrolite are near to 50% disorder.
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