by Dept. of the Interior, Geological Survey, [Books and Open-File Reports Section, distributor] in [Denver, Colo.?] .
Written in English
Includes bibliographical references (leaves [8-10])
|Statement||by Richard A. Robie|
|Series||Open file report -- 88-663, U.S. Geological Survey open-file report -- 88-663|
|Contributions||Geological Survey (U.S.)|
|The Physical Object|
|Pagination||1 microfiche :|
The temperature dependence of elastic properties such as shear modulus, seismic velocities and Debye temperatures has been measured using Hill's averaging method and other thermodynamic methods for five silicate mantle minerals viz. MgAl 2 O 4, Mg 2 SiO 4, Fe 2 SiO 4, Mn 2 SiO 4, and Co 2 SiO 4. The results are found to be in good agreement with Cited by: 3. The contribution becomes apparent at temperatures above – K for Na and K silicates, and above – K for Li metasilicate. With strong thermal agitation, alkali-non-bridging oxygen (NBO) bonds are ruptured with the cations exiting their structural sites to occupy interstitial sites, thereby producing intrinsic Frenkel defects, which contribute to the CP of the Cited by: 1. At least 4 pressure points per mineral are available. Debye-Scherrer investigations of shocked materials re- vealed a gradual lattice breakdown of crystalline matter under shock. Individual mineral species behave selectively- Sheet silicates break down very easily, followeid by tecto silicates. The thermodynamic properties of this material, including heat capacity, entropy, enthalpy, free energy and Debye temperature were also determined as a function of temperature in the range 0 .
Evaluation of their Debye temperatures implies that their vibrational contributions to heat capacity are fully excited at ambient temperatures. The relatively small isothermal compressibilities of these garnets is related to the rigidity of their constituent silicate tetrahedra. Materials with the garnet crystal structure include silicate minerals of importance both in geology, on account of their use in geothermobarometry, and industrially as abrasives. As a consequence of the former, there is considerable published thermodynamic information concerning them. We here examine this thermodynamic information for end-member silicate garnets (some of Author: Leslie Glasser. As natural minerals, silica and silicates constitute by far the largest part of the earth's crust and mantle. They are equally important as raw materials and as mass produced items. For this reason they have been the subject of scientific research by geoscientists as well as by applied scientists in cement, ceramic, glass, and other industries. Silicate ceramics have clearly defined thermal properties and, as such, are particularly useful for advanced engineering and technology. For example, silicate ceramic tiles are used on the space shuttle to shield it from the extreme temperatures of the outer atmosphere. High and Low Technology. Silicates are the most abundant mineral class on.
Silicate weathering can exert a negative feedback on climate because mineral dissolution rates, and hence CO 2 drawdown rates, increase with increasing temperature and . The acoustic Debye temperatures, 0^, for 31 silicate minerals have been calculated from their elastic stiffness (c^'s) constants and/or their heat capacities at very low temperatures. Calculation of the 0^ values from the c^s1 were done on a Hewlett-Parkard series computer using a program written in Hewlett-Packard by: 1. (2) λ s = 2 λ 2 − λ λ p (3 v p − 1) λ p + λ (3 v s − 1) where λ is the measured thermal conductivity, λ p is the thermal conductivity of the pore phase, v p is the pore volume fraction and v s is the solid phase volume fraction. The measured values and the predicted solid phase thermal conductivities of the samples at room temperature are given in Table show a Cited by: Understanding the structure of silicate minerals makes it possible to identify 95% of the rocks on Earth. This module covers the structure of silicates, the most common minerals in the Earth's crust. The module explains the significance of the silica tetrahedron and describes the variety of shapes it takes. X-ray diffraction is discussed in relation to understanding the atomic structure .