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Dynamic simulation of multi-phase mining venture risks resolution
Published in Vladimír Strakoš, Vladimír Kebo, Radim Farana, Lubomír Smutný, Mine Planning and Equipment Selection 1997, 2020
Samuel Frimpong, Jerry M. Whiting
The Moose Gold Venture5 is listed on the TSE 300. This deposit, a large low-grade, sulfide gold orebody, is located on the Queen Charlotte Islands, British Columbia. The geological reserve, at a cut-off grade of 0.033 ounce per tonne, is 52 million tonnes of ore at an average grade of 0.054 ounce per tonne. The ore grade is lognormally distributed with a coefficient of variation of 10 percent. This deposit occurs in the Mesozoic to Tertiary volcanic-sedimentary domain of the coastal British Columbia. It occurs in the sedimentary Skonum Formation, and is bound on the west by an unconformity with the underlying Cretaceous Haida Formation. The footwall occurs within the Haida Formation and dips at about 50 degrees to the east. The formation is characterized by weakly-metamorphosed, well-bedded pyritiferrous black shales of marine origin. Primary minerals in the formation include quartz, feldspar, biotite, hornblende and magnetite. Gold occurs as submicron flakes in silicified sediments, in quartz veins, and in association with pyrites and arsenopyrites.
Characteristics of soils
Published in Yanrong Li, Handbook of Geotechnical Testing, 2019
The solid components in soils are formed by weathering, transportation and sedimentation of parent rocks. Soil-forming minerals can be classified into primary and secondary minerals according to the composition of the parent rock. The soil particles composed of primary minerals have the same properties as those of parent rocks and are usually formed by the physical weathering of parent rocks. The nature of soil particles is relatively stable, has no plasticity and is weak in absorbing water. Common primary minerals are quartz, feldspar, mica, hornblende and pyroxene. Soil particles composed of secondary minerals, whose material composition differs from that of parent rocks, are usually formed from the chemical weathering of parent rocks. Particle size is relatively small and exhibits unstable properties. Soil particles can absorb water. As a result of changes in water content, the volume of soil particles can easily expand or contract. The secondary minerals are mainly clay minerals, the most common being kaolinite, illite and montmorillonite. A small amount of organic matter and soluble salts also exist in soil. The test methods for properties of soil can be found in the specifications GB 50123-1999, BS 1377-3 and ASTM D 2974-14.
Plutonic Rocks
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
The minerals created when a rock initially forms from a crystallizing magma are the rock’s primary minerals. Primary minerals contrast with secondary minerals that form later due to weathering or other forms of alteration when the rock interacts with the environment. Usually, primary minerals do not crystallize all at once, but instead form sequentially, one or more at a time, in a series such as the one described by Bowen’s Reaction Series (discussed in Chapter 5). Evidence for sequential crystallization comes from the presence of phenocrysts that crystalized over much longer times than surrounding groundmass (see Fig. 5.30, Chapter 5, for an example). Additional evidence is provided by rock textures in which early euhedral or anhedral crystals are surrounded by a different mineral that filled in between the early-formed grains.
Effects of Abrasive Rock Type on CVF-Dependent Performance Trends of White Cast Irons in the Inner Circumference Abrasion Test
Published in Tribology Transactions, 2022
E. Demirer, Hamid Pourasiabi, L.J. McInnes, R. Knibbe, J.D. Gates
Two of the most commonly encountered rock types in the Earth’s crust are basalt and granite. Basalts are fine-grained igneous rocks in which the primary minerals are plagioclase (Na-Ca feldspars) and pyroxenes (such as augite, diopside, or spodumene). Informally, the term “granite” is often used to denote a fairly broad range of relatively coarse-grained, inhomogeneous igneous rock types. The primary minerals in granite are feldspars (both orthoclase and plagioclase) and quartz. Greywacke is a sedimentary rock type containing similar primary minerals as granite but in a compact, clay-fine matrix. This results in a slightly lower hardness for greywacke than granite. Table 1 shows the published values of Mohs hardness for these minerals.