Shock Effects in Minerals

Several works showed that almost all eucrites are shocked in varying degree from virtually unshocked to highly shocked (see, e.g., [1,3,25]), altliough tliere are no systematic studies of shock effects in minerals in tlie natural eucrites. Padvaminkai, ALHA81313, and A-87272 [25-27] are cliaracterized by the pres-... 

GPa with both momentum traps. These microfaults are oblique (—30-40°) to the shock front. In many cases glassy veins form at slipped boundaries and penetrate through the sample container to the sample, indicating that these veins are fonned at the time of shock loading. The melt veins are often extensions of the brecciated portion. We did not observe any difference of shock effects in minerals at the given shock pressures (see below). The sample sliocked at... 

The cratered surfaces of asteroids and terrestrial planets underscore the importance of impacts for the formation and evolution of the solar system. Early in the history of the solar system such collisions were the mechanism for accretion of planetesimals and finally the planets themselves [1], The effects of these still ongoing collisions are visible from the megascopic down to the submicroscopic length scale, i.e., they range from large impact craters and their ejecta blankets down to shock-metamorphic effects in minerals [2-4]. These effects form as a result of the interaction of strong shock waves with the affected solid matter. 

E.C.T. Chao, Shock effects in certain rock-forming minerals. Science 156, pp. 192-202 (1967). 

The first three chapters provide an account of the methods used to investigate and compare the shock effects in recovered minerals and rocks. Langenhorst et al. summarize techniques for generation of high pressures by both static and dynamic methods. They further discuss temporal and spatial changes in the dynamic high-pressure field induced by a shock wave. They compare the chemical and physical constitution of calcite samples recovered... 

Chao ECT (1967) Shock effects in certain rock-forming minerals. Science 156 192-202 Stdffler D (1972) Behavior of minerals under shock compression. Fortschr Miner 49 50-113 Stdffler D (1974) Physical properties of shocked minerals. Fortschr Miner 51 256-289 Moroz EM, Svinina SV, Batsanov SS (1972) Changes in the real structure of certain fluorides as a result of compressive impact. J Struct Chem 13 314—316... 

I. Martinez and P. Agrinier, Meteorite impact craters on Earth major shock-induced effects in rocks and minerals. C.R. Acad. Sci. Paris, Sciences de la terre et des planetes 327, pp. 75-86 (1998). 

Meteorites come from more massive parents (mainly minor planets - i.e, asteroids - but also Mars and our Moon) and to get to Earth, their immediate predecessors - meteoroids - can only be excavated from its parent body by an explosive impact. This impact almost always generates short-lived but intense shock effects, results of which are present in many individual meteorites and groups of them (7) but which I do not discuss further here. The impact also provides the impulse necessary for the meteoroid to exceed the parent body s escape velocity e.g. 5.4 km/s for Mars. Thus, meteoritic minerals provide barometers for shock pressures up to -60 GPa (6x10 atm) corresponding to post-shock temperatures >1250°C at much higher pressures (temperatures), these materials vaporize. Incidentally, this explains why Earth receives meteorites from Mars but not Venus, which is closer Venus escape velocity is... 

Some Japanese researchers at the Kyoto University of Medicines have developed a new method for removal of large stones (mineral deposits) in kidney and bladder by using micro-explosive charges without any surgery [118-120]. Recently, applications of underwater shock waves have been extended to various clinical therapies for example, in orthopedic surgery for bone formation [121, 122], in cancer therapy, for enhancement of chemotherapeutic effects [123] and in drug delivery [124, 125]. 

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