Effects of compression direction on the plasticity and rheology of hydrolytically weakened synthetic quartz crystals at atmospheric pressure

Journal Article · Sun Jun 10 00:00:00 EDT 1984 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JB089iB06p04241· OSTI ID:6597863

Linker, M F; Kirby, S H; Ord, A; Christie, J M

A hydrothermally grown synthetic quartz crystal with 370 +- 60 ppm hydroxyl impurity was cut into right rectangular prisms in eight crystallographic orientations. We compressed the prisms under constant axial force corresponding to a uniaxial stress of 140.0 +- 0.5 MPa, and temperatures of 510/sup 0/ and 750/sup 0/C. All but one of the samples sustained permanent axial strains of 2--3%. We established the operating slip systems from specimen shape change, slip bands and dislocation etch pits on polished surfaces, crystallographic orientation changes, stress optical features in thin sections, and transmission electron microscopy. The observed creep behavior and plasticity divided the samples into three groups: (1) Crystals compressed at 45/sup 0/ to (0001) and (2110) and those compressed perpendicular(0111) and perpendicular(0111) deformed principally by slip parallel to (0001). Creep rates were relatively high and were not strongly sensitive to test temperature. Dislocation arrays approximately parallel to (2110) are common. Dislocation loops are elongate parallel to (0001), indicating that the edge segments were more mobile than the screw segements. (2) The second groups of samples were loaded normal to (0001) in three orientation: perpendicular(2110), perpendicular(0110), and at 45/sup 0/ to (1100). These samples deformed primarily by 0 )1010) slip with some evidence for secondary slip on the other systems. They were more creep resistant than the first group and displayed a much higher sensitivity of creep rate to test temperature.

• Research Organization: U.S. Geological Survey
• OSTI ID: 6597863
• Journal Information: J. Geophys. Res.; (United States), Vol. 89:B6
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
QUARTZ
HYDROTHERMAL ALTERATION
PLASTICITY
RHEOLOGY
DEFORMATION
DIFFUSION
DISLOCATIONS
HYDRATION
INTERSTITIAL WATER
MICROSTRUCTURE
SLIP
CHALCOGENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
GROUND WATER
HYDROGEN COMPOUNDS
LINE DEFECTS
MECHANICAL PROPERTIES
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
SILICON COMPOUNDS
SILICON OXIDES
SOLVATION
WATER
152003* - Geothermal Data & Theory- Rock-Water-Gas Interactions