TY  - GEN
N2  - Quartz is an abundant mineral in Earth’s crust whose mechanical behavior plays a significant role in the deformation of the continental lithosphere. However, the ductile rheology of quartz is difficult to measure experimentally at low temperatures without high confining pressures due to the tendency of quartz (and other geologic materials) to fracture under these conditions. Instrumented nanoindentation experiments inhibit cracking even at ambient conditions, allowing for the measurement of the ductile rheology of hard materials over a wide range of temperatures. Here we measure the indentation hardness of four synthetic quartz specimens and one natural quartz specimen with varying water contents over a temperature range of 23ºC to 500ºC from nanoindentation experiments. Yield stress, which is calculated from hardness but is model dependent, is fit to a constitutive flow law for low-temperature plasticity to estimate the athermal Peierls stress of quartz. The yield stresses presented here are lower than those obtained by extrapolating flow laws constrained by experiments at higher temperatures. Indentation hardness and yield stress show no dependence on water content.
DO  - 10.7936/av98-vn87
DO  - DOI
AB  - Quartz is an abundant mineral in Earth’s crust whose mechanical behavior plays a significant role in the deformation of the continental lithosphere. However, the ductile rheology of quartz is difficult to measure experimentally at low temperatures without high confining pressures due to the tendency of quartz (and other geologic materials) to fracture under these conditions. Instrumented nanoindentation experiments inhibit cracking even at ambient conditions, allowing for the measurement of the ductile rheology of hard materials over a wide range of temperatures. Here we measure the indentation hardness of four synthetic quartz specimens and one natural quartz specimen with varying water contents over a temperature range of 23ºC to 500ºC from nanoindentation experiments. Yield stress, which is calculated from hardness but is model dependent, is fit to a constitutive flow law for low-temperature plasticity to estimate the athermal Peierls stress of quartz. The yield stresses presented here are lower than those obtained by extrapolating flow laws constrained by experiments at higher temperatures. Indentation hardness and yield stress show no dependence on water content.
AD  - Washington University in St. Louis
AD  - Washington University in St. Louis
AD  - Washington University in St. Louis
AD  - Washington University in St. Louis
T1  - Experimental Results of Nanoindentation in alpha-Quartz
DA  - 2021-07-22
AU  - Strozewski, Ben
AU  - Sly, Michael
AU  - Flores, Katharine
AU  - Skemer, Philip
L1  - https://data.library.wustl.edu/record/82/files/Experimental_Results_of_Nanoindentation_in_alpha_Quartz.zip
LA  - eng
PY  - 2021-07-22
ID  - 82
L4  - https://data.library.wustl.edu/record/82/files/Experimental_Results_of_Nanoindentation_in_alpha_Quartz.zip
KW  - Earth and related environmental sciences
KW  - quartz
KW  - nanoindentatoin
KW  - yield stress
KW  - SIMS
TI  - Experimental Results of Nanoindentation in alpha-Quartz
Y1  - 2021-07-22
L2  - https://data.library.wustl.edu/record/82/files/Experimental_Results_of_Nanoindentation_in_alpha_Quartz.zip
LK  - https://data.library.wustl.edu/record/82/files/Experimental_Results_of_Nanoindentation_in_alpha_Quartz.zip
UR  - https://data.library.wustl.edu/record/82/files/Experimental_Results_of_Nanoindentation_in_alpha_Quartz.zip
ER  -