Rock fragmentation

Boulders are rock fragments over 10 in. in diameter found in soils. 

Gravel denotes uncon.solidated rock fragments from about 2 mm to 6 in. in size. 

Mbssbauer spectra measured by the Opportunity rover at the Meridiani Planum landing site (see Fig. 8.35) revealed four mineralogical components in Meridiani Planum at Eagle crater jarosite- and hematite-rich outcrop (see Eig. 8.34), hematite-rich soil, olivine-bearing basaltic soil, and a variety of rock fragments such as... 

The clay minerals can now be discussed in terms of their relationship with the phyllosilicates (sheet silicates). It is important to keep clearly in mind here the difference between clay - the material which is dug out of the ground, and which may be a mixture of different clay minerals, together with various nonclay minerals (such as quartz, pyrite, etc), as well as unaltered rock fragments and incorporated organic material (Grim, 1968) - and the clay minerals themselves, which are crystalline compounds of specified stoichiometry and structure. At this stage, we are only considering the structure of the clay minerals. 

In Type II veins arsenopyrite is situated along the walls of the vein, with pyrite overgrowths and as vein fill. Wider veins contain angular to subrounded host rock fragments. These veins contain euhedral arsenopyrite (<4 mm) and pyrite (< 3 mm) (Fig. 3). Both minerals have Au enriched rims and cores with an intermediate zone devoid of detectable Au. 

Among the merchants, continued Lemery, we find two general species of antimony, die unworked mineral and die artificial die former is taken from the mine loaded or mixed with many rock fragments, which the artisans call gangue.. . . This kind of antimony is not very common at die apodiecaries shops because it does not sell well.. . . ... 

On one of these expeditions he may have found in a spring near his home at New London, Connecticut, the rock fragment of columbite which his grandson sent to Sir Hans Sloane (1660-1753) in London (4). ... 

Deposit of spoil, typically in the form of a large pile of rock fragments (synonyms biug I Scot land), culm bank (India), gob pile (Easlent USA), nvi.vrc rotk pile (Australia. Canada)... 

Re-1870s evolution diagram for the St. Severin LL6 chondrite. The isochron is generated from three whole-rock fragments and two metal separates. Deviations from the best-fit line are shown in part in 103 in the inset. Modified from Chen etal. (1998) using X = 1.666 x 10-11 yr ... 

F-M, L Gn-Gr, angular-subrounded, argillaceous micaceous sandstone, rock fragments (alluvial)... 

Gravel is also a popularly used term for loose accumulation of rock fragments, such as detrital sediment associated especially with streams or beaches, composed predominantly of more or less rounded pebbles and small stones, and mixed with sand that may compose 50-70% of the total mass. 

Further, pelletized TNT performed satisfactorily in wellbore shots in wells 150-385 ft deep. Fractures were created between wells as indicated by airflow tests, but numerous other evaluation techniques did not indicate the extent of rock fragmentation. 

Living surface vegetation, fresh litter, big roots and rock fragments (stones) are removed. 

Figure 1.2 Contact traces of yellowish-gray soil on the suspect s shoes (left) and the control soil specimen from the bank of a river (right), which comprises a mixture of 95% coarse gravel and rock fragments and only 5% clay and silt (< 50 pm fraction). (See color insert following p. 178.)...

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