Rock sample, properties

Samples. Three immature sulfur-rich sedimentary rock samples were selected for study of both the kerogens and extractable bitumens. Selected properties of the specific samples together with references to previous descriptions and investigations of these deposits are as follows ... 

Fountain D. M., and Salisbury M. H. (1995) Seismic properties of rock samples from the Pikwitonei granuhte belt—God s lake domain crustal cross section, Manitoba. Can. J. Earth Sci. 33(5), 757-768. 

While a full-scale field loading test, properly performed and interpreted, will reliably define the foundation soil interaction, such tests are generally not feasible. Thus, the way a soil or rock mass responds to being stressed is usually determined by previous experience in similar conditions, by extrapolating the results of small load tests or by using specific soil properties in various empirical formulae. These soil properties are sometimes inferred from previous experience, but more often reflect the results of laboratory and field tests on soil and rock samples. 

Samples of rock can only be obtained by coring , that is, by drilling into a rock mass with a hollow drill bit. Bits are available in many sizes, with the cutting edges made of tempered steel or of steel in which many tiny industrial diamonds are imbedded. The solid portions of the rock cores obtained are considered undisturbed , and representative of the properties of the in-situ rock. The makeup of a rock sample is a function of the relation between the sample size and the joint or fracture system, as shown in Figure 1.3. 

Background How do scientists identify unknowns What about an unidentified rock sample from the moon, for example Scientists compare the moon rock s properties with those of known rocks on earth. By seeking correlations—and ideally, a match—scientists can determine the moon rock s composition. In this lesson, students follow a similar process to discover the Identities of their five chemical unknowns. They compare the data they have collected through observing and testing the unknowns (contained in their test summary tables from Lesson 11) with data from a reliable source of information (contained in Record Sheet 12-A Chemical Information Sheet). 

The discovery of buckyball generated tremendous interest within the scientific community. Here was a new allotrope of carbon with an intriguing geometry and unknown properties to investigate. Since 1985 chemists have created a whole class of fullerenes, with 70, 76, and even larger numbers of carbon atoms. Moreover, buckyball has been found to be a natural component of soot, and the fullerenes Ceo and C70 turned up in a rock sample from northwestern Russia. 

Figure 17. Comparison of 5 O values with MgO concentrations in whole-rock samples from Krafla, a central volcano complex in Iceland s northern neovolcanic zone data from Nicholson et al. (1991). MgO-poor, low-5 0 rhyolites and dacites are interpreted as melts of hydrothermally altered crustal rocks mixing between these melts and basalts generates the trend of decreasing 5 0 with decreasing MgO. It is not clear from studies of such highly evolved suites whether subtle differences in between the most magnesian lavas (MgO of between 8 and 9 wt %) and typical terrestrial basalts are caused by subtle crustal contamination or are instead a property of the sub-Icelandic mantle.

In this case, the crucial data appears to require higher precision than the " °Ar- Ar technique was capable of when the problem was first attacked. Using mineral separates, instead of whole rock samples (Pb-Pb and 1-Xe), was the other key step. Although " °Ar- Ar experiments are capable of the required precision, whether any minerals within the meteorites will have remained closed systems for the entire 4.5 Ga remains to be seen. If so, the logical next step is to use mineral separates so that the extensive terrestrially-derived database on diffusion properties can be used to define closure temperatures (McDougall and Harrison 1999). 

In the DECOVALEX I project, modeling was conducted on three hypothetical BMTs and six TCs, involving three small laboratory tests of rock samples and fractures, and three large field tests. Details may be found in Jing et al. (1995). One of the BMTs simulated a Swedish KBS-3 disposal concept in a fractured granitic rock with a fracture network system and properties similar to those of the Stripa granite. This case will be presented in more detail in section 5. 

The suction pressure is not uniform because of the heterogeneity in pore size and the humidity gradient existing inside the rock samples during the cure consequently, the differential strains thus created may provoke micro-cracks and decrease the elastic properties of the material. There is a therefore competition between the role of the confining pressure and the creation of micro-cracks due to desiccation. 

Grouping or clustering of rock samples according to similar elemental patterns or of material samples with respect to comparable chemical composition and technological properties. 

Simple lahoratory and field strength test. Useful aid to core logging Carried out on intact samples with no discontinuities and yields data on the rock material properties. The length to diameter ratio of 2 1 is a minimum for cylinders... 

Usually carried out on intact samples with no discontinuities and yield data on rock material properties. Larger samples may contain one or more discontinuities, in which case the data relates to the properties of the rock mass... 

The rock samples show different properties and failure mechanism after peak stress under different... 

The rock samples show the property of strainsoftening after peak and coupling shear splitting failure mechanism under low confining pressure (1 MPa) while that of ideal elastoplastic after peak and dilative shear failure mechanism under high confining pressure (30 MPa). 

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