Deep Ductile Shear Zone Facilitates Near?Orthogonal Strike?Slip Faulting in a Thin Brittle Lithosphere

A ductile shear zone terminating a brittle strike-slip fault: The gypsum- dominated Paluzza-Comeglians shear zone as western extension of the Fella- Save fault, Southern Alps

Compressive and extensive horsetails are common structures on the lateral termination of brittle strike-slip faults, which forms within the shallow continental crust. Here we report another possibility, the lateral termination of a brittle strike-slip fault in a formation-parallel low-temperature ductile shear zone within sulphatic, gypsum-dominated evaporites. In the Southern Alps, over a dist...

Forced tearing of ductile and brittle thin sheets.

Tearing a thin sheet by forcing a rigid object through it leads to complex crack morphologies; a single oscillatory crack arises when a tool is driven laterally through a brittle sheet, while two diverging cracks and a series of concertinalike folds forms when a tool is forced laterally through a ductile sheet. On the other hand, forcing an object perpendicularly through the sheet leads to radi...

Engineering ductile fracture in brittle-matrix composites

This letter describes a newly discovered phenomenon: ductile fracture in cementitious materials. The brittle nature of materials such as concrete and ceramics has prompted the development of various approaches to enhance their fracture toughness. Fibre reinforcement has been the common focus in the toughening of the brittle materials. Two types of fracture have been observed to date in cementit...

Ductile or Partial Ductile Mode Machining of Brittle Materials

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

Mechanics of low-angle extensional shear zones at the brittle-ductile transition