thumbnail

Hydrothermal studies in a new diamond anvil cell up to 10 GPa and from -190??C to 1200??C

Pure and Applied Geophysics PAGEOPH

By:
, , ,
DOI: 10.1007/BF00998341

Links

Abstract

The new hydrothermal diamond anvil cell (HDAC) has been designed for optical microscopy and X-ray diffraction at pressures up to 10 GPa and temperatures between -190??C and 1200??C. Laser light reffected from the top and bottom anvil faces and the top and bottom solid sample faces produce interference fringes that provide a very sensitive means of monitoring the volume of sample chamber and for observing volume and refractive index changes in solid samples due to transitions and reactions. Synchrotron radiation has been used to make X-ray diffraction patterns of samples under hydrothermal conditions. Individual heaters and individual thermocouples provide temperature control with an accuracy of ??0.5??C. Liquid nitrogen directly introduced into the HDAC has been used to reduce the sample temperature to -190??C. The ??-?? phase boundary of quartz has been used to calculate the transition pressures from measured transition temperatures. With this method we have redetermined 5 isochores of H2O up to 850??C and 1.2 GPa at which the solution rate of the quartz became so rapid that the quartz dissolved completely before the ??-?? transition could be observed. When silica solutions were cooled, opal spherules and rods formed. ?? 1993 Birkha??user Verlag.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Hydrothermal studies in a new diamond anvil cell up to 10 GPa and from -190??C to 1200??C
Series title:
Pure and Applied Geophysics PAGEOPH
DOI:
10.1007/BF00998341
Volume
141
Issue:
2-4
Year Published:
1993
Language:
English
Publisher location:
Birkha??user-Verlag
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
487
Last page:
495
Number of Pages:
9