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Direct observation of frictional contacts: New insights for state-dependent properties

January 1, 1994

Rocks and many other materials display a rather complicated, but characteristic, dependence of friction on sliding history. These effects are well-described by empirical rate- and state-dependent constitutive formulations which have been utilized for analysis of fault slip and earthquake processes. We present a procedure for direct quantitative microscopic observation of frictional contacts during slip. The observations reveal that frictional state dependence represents an increase of contact area with contact age. Transient changes of sliding resistance correlate with changes in contact area and arise from shifts of contact population age. Displacement-dependent replacement of contact populations is shown to cause the diagnostic evolution of friction over a characteristic sliding distance that occurs whenever slip begins or sliding conditions change. ?? 1994 Birkha??user Verlag.

Publication Year 1994
Title Direct observation of frictional contacts: New insights for state-dependent properties
DOI 10.1007/BF00874332
Authors J.H. Dieterich, B.D. Kilgore
Publication Type Article
Publication Subtype Journal Article
Series Title Pure and Applied Geophysics PAGEOPH
Index ID 70016962
Record Source USGS Publications Warehouse