Shock processes in porous quartzite: Transmission electron microscope observations and theory

Kieffer, S. W.; Phakey, P. P.; Christie, J. M.

doi:10.1007/bf00375110

Cited by 208 publications

(273 citation statements)

References 38 publications

Supporting

Mentioning

258

Contrasting

Unclassified

Order By: Relevance

“…Subsequent tests used Coconino Sandstone (density = 1.78 g cm −3 , typical grain size of 0.15 mm and porosity ~23%) selected for its prevalence at the Meteor Crater impact site (Shoemaker and Kieffer 1974). It has been suggested that the presence of pore water, perhaps related to the proximity of a water table to the impact site, may have influenced the mode in which the target material failed upon impact (Kieffer et al 1976).…”

Section: Methodsmentioning

confidence: 99%

Laboratory impacts into dry and wet sandstone with and without an overlying water layer: Implications for scaling laws and projectile survivability

Baldwin

Milner

Burchell

et al. 2007

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Abstract-Scaling laws describing crater dimensions are defined in terms of projectile velocity and mass, densities of the materials involved, strength of the target, and the local gravity. Here, the additional importance of target porosity and saturation, and an overlying water layer, are considered through 15 laboratory impacts of 1 mm diameter stainless steel projectiles at 5 km s −1 into a) an initially uncharacterized sandstone (porosity ~17%) and b) Coconino Sandstone (porosity ~23%). The higher-porosity dry sandstone allows a crater to form with a larger diameter but smaller depth than in the lower-porosity dry sandstone. Furthermore, for both porosities, a greater volume of material is excavated from a wet target than a dry target (by 27-30%). Comparison of our results with Pi-scaling (dimensionless ratios of key parameters characterizing cratering data over a range of scales) suggests that porosity is important for scaling laws given that the new data lie significantly beneath the current fit for ice and rock targets on a π v versus π 3 plot (π v gives cratering efficiency and π 3 the influence of target strength). An overlying water layer results in a reduction of crater dimensions, with larger craters produced in the saturated targets compared to unsaturated targets. A water depth of approximately 12 times the projectile diameter is required before craters are no longer observed in the targets. Previous experimental studies have shown that this ratio varies between 10 and 20 (Gault and Sonett 1982). In our experiments ~25% of the original projectile mass survives the impact.

show abstract

Section: Methodsmentioning

confidence: 99%

Laboratory impacts into dry and wet sandstone with and without an overlying water layer: Implications for scaling laws and projectile survivability

Baldwin

Milner

Burchell

et al. 2007

Meteorit & Planetary Scien

View full text Add to dashboard Cite

show abstract

“…Inferred peak pressures for the bulk meteorite are <20 GPa (Nakamura et al 1992), which would not be expected to lead to widespread melting. Shock waves are, however, notorious for producing local melting along grain boundaries and highly variable effects in heterogeneous, especially porous, materials by frictional heating (e.g., Kieffer et al 1976;Sharp and DeCarli 2006;Stöffler et al 1988). Where a shock wave passes through a porous material, or through a grain boundary between two dissimilar materials, considerable increases in peak pressures may be attained relative to ambient values nearby due to compaction effects and differences in the mechanical impedance of materials at grain boundaries (e.g., Sharp and DeCarli 2006).…”

Section: Formation Of Leoville Glass Veinsmentioning

confidence: 99%

The formation of boundary clinopyroxenes and associated glass veins in type B1 CAIs

Paque

Beckett

Ishii

et al. 2009

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Allende spinels display either direct spinel-melilite contact or an intervening boundary clinopyroxene between the two phases. Spinel-melilite interfacial regions in a Leoville B1 are more complex, with boundary clinopyroxene, as observed in Allende, but also variable amounts of glass, secondary calcite, perovskite, and an Mg-, Al-, OH-rich and Ca-, Si-poor crystalline phase that may be a layered double hydrate. One possible scenario of formation for the glass veins is that open system alteration of melilite produced a porous, hydrated aggregate of Mg-carpholite or sudoite + aluminous diopside that was shock melted and quenched to a glass. The hydrated crystalline phase we observed may have been a shocked remnant of the precursor phase assemblage, but is more likely to have formed later by alteration of the glass. In the mantle, boundary clinopyroxenes may have been crystallized from Ti-rich liquids formed by the direct dissolution of perovskite and an associated Sc-Zr-rich phase or as a reaction product between dissolving perovskite and liquid. In the core, any perovskite and associated Ti-enriched liquids that may have originally been present disappeared before the growth of boundary clinopyroxene, and the observed boundary clinopyroxene may have nucleated and grown from the liquid, along with the larger core clinopyroxene.

show abstract

“…structure of the original crystalline quartz is severely deformed, so that the quartz has been transformed into a distinct amorphous phase (Miiller, 1969;Kieffer et al, 1976a;Goltrant et al, 1991Goltrant et al, , 1992.…”

Section: 52mentioning

confidence: 99%

“…4.16, 4.18, and 4.27). Kie_;, Kieffer et al, 1976a. Despite :hese similarities, a growing amount of data now indicates tk at sedimentary rocks, especially porous ones, respond diffe rently to shock waves than do nonporous crystalline rock.…”

Section: Pdf Orientationsmentioning

confidence: 99%

“…A more important difference between porous and nonporous rocl:s is that a shock wave passing through porous sediments _¢ill generate more heat than in passing through crystalline ocks, chiefly because more of the shock-wave energy is ab _orbed by the numerous grain interfaces and pore spaces in tte sediment (Kieffer, 1971;Kieffer et al, 1976a;Kiefferand 9imonds, 1980;StOffler, 1984). As a result, extensive meltint ;will occur at lower shock pressures in sediments than in cry talline rocks, i.e., at about 15-20 GPa in sandstone vs. 50 -60 GPa in crystalline rocks (stoJ:Jler, 1972(stoJ:Jler, ,1984.…”

Section: Pdf Orientationsmentioning

confidence: 99%

See 1 more Smart Citation

Traces of catastrophe: a handbook of shock-metamorphic effects in terrestrial meteorite impact structures

French

1999

Choice Reviews Online

View full text Add to dashboard Cite

Shock processes in porous quartzite: Transmission electron microscope observations and theory

Cited by 208 publications

References 38 publications

Laboratory impacts into dry and wet sandstone with and without an overlying water layer: Implications for scaling laws and projectile survivability

Laboratory impacts into dry and wet sandstone with and without an overlying water layer: Implications for scaling laws and projectile survivability

The formation of boundary clinopyroxenes and associated glass veins in type B1 CAIs

Traces of catastrophe: a handbook of shock-metamorphic effects in terrestrial meteorite impact structures

Contact Info

Product

Resources

About