Igneous, sedimentary and metamorphic rocks: origins and types. What is single mo
ID: 233508 • Letter: I
Question
Igneous, sedimentary and metamorphic rocks: origins and types. What is single most characteristic feature of sedimentary rocks? Describe golden ores and gold extraction. What Is the difference between karat and can Describe mechanisms of lunar and solar eclipses, (drawing) Define renewable and nor-renewable resources. What is the difference between resources reserves? What are ores? Describe the process of ores creation by hydrothermal solution weathering and erosion. 117 Define and describe sedimentary systems, (drawing) Oil and natural gas: use, origins, types of traps, (drawing) Rock cycle - describe the process of re cycling igneous, sedimentary and metamorphic r (drawing). Id. Relative and absolute dating. Fossils and correlation of geological events. In simple test how to detect a diamond from other classy minerals. Explain the different between carat and karatExplanation / Answer
7 ) The three types of rocks are Igneous , sedimentary , metamorphic
Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.
Coarse grained intrusive igneous rocks that form at depth within the crust are termed as abyssal; intrusive igneous rocks that form near the surface are termed hypabyssal.
Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water.Sedimentary rocks can be subdivided into four groups based on the processes responsible for their formation: clastic sedimentary rocks, biochemical (biogenic) sedimentary rocks, chemical sedimentary rocks, and a fourth category for "other" sedimentary rocks formed by impacts, volcanism, and other minor processes.
Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form".The original rock (protolith) is subjected to heat (temperatures greater than 150 to 200 °C) and pressure (1500 bars), causing profound physical and/or chemical change. The protolith may be a sedimentary rock, an igneous rock or another older metamorphic rock.
Sedimentary rocks form as layer upon layer of sediment accumulate in various depositional environments. These layers, or strata, are probably the single most characteristic feature of sedimentary rocks. Lithification occurs when sediment has been deposited and accumulates at the earth's surface or in bodies of water to form a rock over time.
8) Gold occurs principally as a native metal, usually alloyed to a greater or lesser extent with silver (as electrum), or sometimes with mercury (as anamalgam). Native gold can occur as sizeable nuggets, as fine grains or flakes in alluvial deposits, or as grains or microscopic particles embedded in other rocks.
Ores in which gold occurs in chemical composition with other elements are comparatively rare. They include calaverite, sylvanite, nagyagite, petzite and krennerite.
Gold extraction or recovery from its ores may require a combination of comminution, mineral processing,hydrometallurgical, and pyrometallurgical processes to be performed on the ore. Gravity concentration has been historically the most important way of extracting the native metal using pans or washing tables. Amalgamation with mercury was used to enhance recovery, often by adding it directly to the riffle tables, and mercury is still widely used in small diggings across the world. However, froth flotation processes may also be used to concentrate the gold. In some cases, particularly when the gold is present in the ore as discrete coarse particles, a gravity concentrate can be directly smelted to form gold bars.
If the gold can not be concentrated for smelting, then it is leached by an aqueous solution:
Gold smelting is done to remove mercury and /or iron .
Gold refining or parting is primarily the removing of silver from gold and therefore increasing the purity of gold.
difference between karat and carat
One carat is equal to 200 milligrams, which is the same as 0.2 grams. A two-carat diamond would weigh 400 milligrams (0.4 grams).
A karat, on the other hand, is a measure of purity when referring to gold. “24 karat” refers to pure gold, which is not often used in jewelry because it is very soft.
9 ) All solar eclipses involve the moon passing between the Sun and the Earth, and in the process, casting a shadow upon the Earth’s surface. However, the type of eclipse that can be observed from a given location is dependable on the way the moon passes between the Earth and the Sun, whether it passes directly, or only partly between the Earth and Sun.
For a solar eclipse to occur, there are firstly 2 factors that must be fulfilled. Firstly, There must be a new moon. Secondly, the New Moon must be in the ecliptic, on the Line of nodes of the intersection of the ecliptic plane and the orbital plane of the moon.
There are 2 situations that a solar eclipse can occur.
Case 1: Shadow misses the surface of the Earth
In the first situation, the New Moon does not lie exactly on the orbital plane of the Earth between the Sun and the Earth, but is above or below the Earth’s orbital plane. This causes the moon’s umbral shadow to miss the surface of the Earth and fall away into space.
In this case, the umbra does not reach the Earth at all, resulting in a partial eclipse where the umbra will either pass North or South of the Earth.
Case 2: Shadow falls across the surface of the Earth
In the second situation, the New Moon coincides with the time when the moon crosses the orbital plane of the Earth and the umbra strikes the Earth, falling across the Earth’s surface and tracing out a path of totality (if it's a total solar eclipse) on the Earth's surface. The moon will also block off the face of the Sun totally enabling observers within the area of the umbra to experience a total solar eclipse.
A lunar eclipse can only happen at Full Moon, it is because the Earth comes between the Sun and the Moon as if the Moon slips into the shadow of the Earth. Usually, people on the Earth’s night hemisphere can see the same lunar eclipse for the whole night.
First penumbral contact occurs when the Moon first enters Earth’s penumbra, while first umbral contact marks when the Moon is first shadowed by Earth’s darker umbra.
Second umbral contact takes place at the beginning of totality, when the Moon is fully eclipsed by the Earth’s umbra, and third umbral contact occurs at totality’s end.
Last umbral contact marks when the Moon completely leaves Earth’s umbra, and second penumbral contact occurs when the Moon leaves the penumbra.