Magnetic rocks

This book is devoted to the fabrication, characterization, experimental investigation, theoretical understanding, and utilization of advanced magnetic nanostructures. Focus is on various types of bottom-up and top-down artificial nanostructures, as contrasted to naturally occurring magnetic nanostructures, such as iron-oxide inclusions in magnetic rocks, and to structures such as perfect thin films. 

Becker, J. K., Siegesmund, S. Jelsma, H. A. 2000. The Chinamora batholith, Zimbabwe structure and emplacement-related magnetic rock fabric. Journal of Structural Geology, 22, 1837-1853. 

Magnetic minerals have fascinated man since they were first used as compasses by the Chinese over 4000 years ago. Their scientific study has given rise to the interrelated disciplines of mineral magnetism, rock magnetism, and paleomagnetism, which have contributed to some of the most important scientific discoveries of the last century and continue to be at the forefront of scientific investigation at the beginning of this one. 

Most fluids are diamagnetic and have only a very small influence on the magnetic rock properties. For liquids, Kobranova (1989) gives the following susceptibility values ... 

Keywords plate tectonics, sedimentary basins, source rocks, maturation, migration, reservoir rocks, traps, seismic, gravity survey, magnetic survey, geochemistry, mudlogs, field studies. 

Finally, selective separation and dewatering of one suspended substance in a slurry containing different minerals or precipitates is possible by selectively adsorbing a magnetic material (usually hydrophobic) onto a soHd that is also naturally or chemically conditioned to a hydrophobic state. This process (Murex) was used on both sulfide ores and some oxides (145). More recently, hydrocarbon-based ferrofluids were tested and shown to selectively adsorb on coal from slurries of coal and mineral matter, allowing magnetic recovery (147). Copper and zinc sulfides were similarly recoverable as a dewatered product from waste-rock slurries (148). 

The life of a cage may be a few months and may produce 9000 Mg (10,000 tons) of quany rock. A gray-iron cage is used for alumina grinding, with metal particles removed magnetically. The advantage of... 

A shaker tube equipped with a 1200-atm. rupture-disk assembly was used by the submitters. The checkers used a 1270-ml. stainless steel rocking autoclave fitted with a thermocouple well that extended into the reaction mixture and a stainless steel 5000-p.s.i. rupture disk. The agitation rate was 58 cycles per second. Attempts to use a magnetically stirred autoclave were unsuccessful. 

Magnetic susceptibility data are inferred to have been reflected by hydrothermal activity. The magnetic susceptibility data on the sedimentary rocks are shown in... 

Figure 1.160. Magnetic susceptibility value of studied rock samples. Most younger two samples (NK-12 and -13) of Nishikurosawa shale have anomalously high magnetic susceptibility value.

Latham AG, Ford DC (1993) The paleomagnetism and rock magnetism of cave and karst deposits. In Applications of Paleomagnetism to Sedimentary Geology. Aissaoui DM, McNeill DF, Hurley NF (eds). SEPM Special Publications. 49 149-155... 

Natural rocks seldom have a single pore size but rather a distribution of pore sizes. If all pores are in the fast-diffusion limit, have the same surface relaxivity and have no diffirsional coupling, then the pores will relax in parallel with a distribution of relaxation times that corresponds to the distribution of the pore sizes. The magnetization will decay as a sum of the exponentials as described by Eq. (3.6.4). 

L. L. Latour, R. L. Kleinberg, A. Sezginer 1992, (Nuclear magnetic resonance properties of rocks at elevated temperatures), JCIS 150 (2), 535-548. 

E. J. Fordham, W. E. Kenyon, D. J. Wilkinson 1999, (Forward models for nuclear magnetic resonance in carbonate rocks), Log Analyst 40 (4), 260-270. 

A large portion of titanium minerals (ilmenite, rutile) are produced from heavy mineral sands using physical preconcentration methods including gravity, magnetic and electrostatic separation. Over the past 30 years, advances have been made using flotation, where ilmenite, mtile and perovskite can be effectively recovered from both heavy mineral sands and hard rock ores using flotation methods. 

Blichert-Toft J, Chauvel C, Albarede F (1997) Separation of Hf and Lu for high-precision isotope analysis of rock samples hy magnetic sector-multiple collector ICP-MS. Contrih Mineral Petrol 127 248-260 Cameron AE, Smith DH, Walker RL (1969) Mass spectrometry of nanogram-size samples of lead. Anal Chem 41 525-526... 

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