bigmeech85

The source of the nitrogen in most fertilizers used today is/are:

Atmospheric nitrogen

Intensely weathered soils are often red in color due to

Iron accumulation and concentration

The metal extracted in large quantities from brines, including sea water, is:

Magnesium

The principal metal for which the nodules of the deep sea floor will likely be exploited is:

Manganese

The primary elements that make sea water salty are:

Sodium and chloride

Asbestos has well -documented, hazardous effects on human health. Having said that, it is important to remember that

The most widely used variety of asbestos is safer than other varieties of asbestos, Asbestos does not pose a health risk unless the fibers become air borne

Bauxite deposits are usually found in

Tropical countries, Areas where aluminum rich rocks have been intensively weathered

The level of water in Mono Lake has decreased in recent years because of

diversion of surface streams that once flowed into Mono Lake

Mississippi Valley types deposits

Are sedimentary in origin, Are mined for lead, zinc, and other metals, Are generated in shales but actually found in limestone

The major consumptive use of silver is

As silver iodide in photographic films

An example of a mafic, layered igneous intrusion containing ores of important metals such as chromium concentrated by crystal settling is the

Bushveld Igneous Complex in South Africa

Pearls have the same chemical composition as what common mineral?

Calcite

Describe how cement is made, the mineral products needed to make cement, and their sources. What is the difference between cement and concrete?

Cement is a powdered mixture of lime (from limestone), alumina (from clay or shale), and silica (from quartz sand). To make cement, these materials are crushed, mixed, and heated to high temperatures to drive of carbon dioxide and water, producing a partially molten material. The result is cooled, powdered, and sold as cement. Concrete is produced by mixing cement with water and an aggregate such as sand, gravel, or crushed rock. As this mixture sets and dries, it produces "instant rock" with a structure of interlocking calcium silicate crystals.

Guano deposits are most likely to be found in

Coastal desert environments

Copper was the first metal to be mined and used in the ancient world for all of the following reasons except

Copper deposits are abundant in Greece and Rome

Describe the formation of a copper porphyry deposit, and explain the tectonic setting where ore deposits of this type are formed.

Copper porphyrys are formed during intrusion of water-rich magmas. As crystallization occurs, many metals, being incompatible with common igneous minerals, are excluded and concentrated in a water rich, metaliferous fluid. If sufficient pressure exists in the crystallizing magma, explosions may shatter the intrusion, creating abundant, small fractures into which these metal rich fluids are intruded and crystallized. The resulting veins are too small to be mined directly, instead the entire deposit is mined by open-pit mining and the metals are separated during processing and smelting. Water-rich magmas are produced at subduction zones by melting of oceanic curst, consequently copper porphyry type deposits are found in geologic settings where subduction is occurring or has occurred in the past, such as the west coast of North and South America.

Earth differentiated into core, mantle, and crust based upon differences in:

Density

The major use of sulfur today is in making:

Fertilizer

Minerals used in the chemical industry are primarily obtained how?

From evaporite deposits

Which of the following reservoirs of water in the global hydrologic cycle contains the largest volume of water?

Glaciers

The major component of plaster is

Gypsum, from evaporites

Most metallic mineral deposits can be found near active or formerly active plate boundaries because:

Igneous and metamorphic processes occur in this tectonic setting

Which of the following are abundant metals?

Iron and magnesium

The clay mineral_______ is used to make porcelain.

Kaolinite

The major component of cement is

Lime, from limestone

dentify the four major types of iron ores and describe how they are formed.

Magnetite and hematite are iron oxide minerals that may become concentrated in a mafic (iron rich) igneous intrusion by crystal settling. Iron ores may also be formed when reduced iron (which is soluble in water) becomes oxidized (which is insoluble in iron) which is precipitated. There are three types of deposits of this type. Bog iron deposits are highly localized but historically important because they can be found in Europe and North America and were the first type of sedimentary iron deposit to be exploited for iron making. Ironstones form when reduced iron carried in groundwater becomes oxidized. Banded iron formations are the most important iron ore today, but were formed billions of years ago, when the earth was transformed from a reduced to an oxygenated atmosphere by the evolution of photosynthetic organisms. This caused the oxidation and precipitation of the soluble reduced iron that was present in seawater from rock weathering. Finally, because oxidized iron is insoluble, it may become concentrated by residual weathering in soils. Such soils are called lateritic, although these represent a large potential resource of iron they are not being mined currently due to environmental problems that would result from such large-scale operations.

How has the major source of nitrogen in fertilizers changed over time? How is most nitrogen used in fertilizers obtained today?

Nitrogen is an essential element for plant growth, yet is not normally found in rocks or weathered mineral matter (soils) formed from rocks. Nitrogen is found in organic matter, and so the fertility of soils can be enhanced by adding organic matter, such as manure or crop residues. Guano is an organic source of nitrogen from accumulations of bird or bat droppings and was once mined for use as fertilizers. Caliches are deposits of nitrate minerals formed in certain hyper-arid environments such as the Channel Islands or Atacama Desert. Neither guano nor caliches are major sources of nitrogen for fertilizer production today. Instead most nitrogen in fertilizers today is artificially fixed from atmospheric nitrogen using the Haber-Bosch processes. The process reacts carbon monoxide (from the controlled combustion of a fossil fuel like coal or natural gas) with atmospheric nitrogen to make ammonia. The ammonia is then oxidized to nitrate.

Define porosity and permeability, and how these aquifer properties determine the volume and rate of groundwater flow. What are aquitards and how do aquitards affect groundwater flow?

Porosity is the total volume of empty pore space and is affected by size, shape, sorting and arrangement of particles. Porosity is also expressed as a fraction or percent. Porosity determines how much water can be held in a solid, and thus affects the volume of groundwater flow. Permeability is how easily a solid allows a liquid to flow through it. It is determined by how large or small the pore spaces are and the connectivity of them. There will be low permeability if the pore spaces are not connected. Permeability affects the rate at which groundwater flows, because a solid with a high level of permeability permits the passage of water easier, allowing for swifter flow. Aquitards are non permeable layers that restrict water movement. They are often made of clay or shale. These aquitards have a bounding effect on water tables, preventing vertical movement of an aquifer in either one direction, or both. Aquitards affect the way in which groundwater flows by limiting the directions in which it can flow, for example, where an aquifer's water supply would begin to flow downwards, it would flow laterally instead when blocked by an aquitard. The groundwater may emerge as a spring where the aquitard intersects the ground surface.

Types of minerals that may be ores for scarce metals include

Silicate minerals (by solid solution), Oxide minerals, Sulfide minerals, and Native elements

Describe the Earth's internal structure in terms of both chemical composition and physical properties.

The earth is divided into three layers, a crust, a mantle and a core, that differ in their chemical composition. The crust is the thin outer layer, consisting primarily of oxygen, silicon and aluminum. It is further subdivided into continental and oceanic crust. The oceanic crust is thinner and denser, and is similar in composition to basalt (Si, O, Ca, Mg, and Fe). The continental crust is thicker and less dense, and is similar to granite in composition (Si, O, Al, K, and Na). The mantle is made of magnesium, iron and silicon. The core is almost exclusively iron and nickel. The outer core is liquid iron and the inner core is solid iron. The mantle and crust are further divided into the lithosphere, asthenosphere and mesosphere, depending on their physical properties, namely how close the material is to its melting point. The lithosphere is cold and rigid and includes the curst and uppermost part of the mantle where rocks are far below their melting point. Further down in the mantle is the asthenosphere where rocks are weak and can flow because they are close to their melting point. The deepest part of the mantle is the mesosphere where rocks are gain strong and below their melting point due to the high pressure.

How does the lithosphere differ from the asthenosphere?

The lithosphere is strong and rigid while the asthenosphere is weak and plastic

When two oceanic plates collide

The older plate will subduct

Rank the reservoirs of water in the global hydrologic cycle in order of decreasing volume of water. Explain why the atmosphere is such an important component of the global hydrologic cycle even though the atmosphere holds only a small amount of water.

The reservoirs of the global water cycle, in order from largest to smallest, are the oceans, glaciers and ice caps, groundwater, freshwater lakes and rivers, and the atmosphere. Although the atmosphere is the smallest reservoir in terms of the volume of water it contains, it plays a tremendously important role as a transport mechanism bringing water from the oceanic to the various land reservoirs (glaciers, groundwater, freshwater lakes and streams).

Mineral deposits are called "non-renewable" because

They are formed much more slowly than the rate at which they are exploited

Rutile and ilmenite are the primary mineral sources of what metal?

Titanium

Is shale a good aquitard

Yes

To be useful as a source of water (an aquifer), a rock must be

both porous and permeable

Conflicts between different instream water uses arise because

different discharge patterns are needed for each instream use

Hydrothermal ore deposits are

formed by deposition of dissolved minerals from hot fluids, associated with contact metamorphism

Accessible and usable water is found mostly as

groundwater

Describe the two basic types of igneous processes that may produce an ore deposit during the crystallization of magma, and provide examples of metals that may be concentrated by these processes.

here are two basic types of igneous processes that may produce an ore deposit. First, as magma crystallizes, heavy dense minerals that crystallize first may become concentrated near the bottom of the magma chamber. This is known as crystal settling and may produce deposits of metals such as iron and chromium. Second, as crystallization proceeds some elements are not incorporated into the crystal structure of common igneous minerals. These elements are said to be incompatible and become concentrated in the water rich fluid that remains after much of the magma has crystallized. This metal rich fluid is also rich in silica and is squeezed into veins or fractures and crystallizes as metal bearing quartz vein. Metals that may be concentrated in such a s fluid include copper and gold. The metal rich fluid may also migrate hot of the intrusion and crystallize in the zone of contact metamorphism surrounding the intrusion.

The rate of groundwater flow is proportional to the

hydraulic conductivity

A perennial stream

is a site of groundwater discharge, is also known as a gaining stream

What are potential consequences of groundwater overdraft?

land subsidence and cracked building foundations, compression of the aquifer, resulting in a permanent loss of water storage capacity, salt water intrusion

According to plate-tectonic theory, plates of rigid __________ move over a weak ___________ below.

lithosphere, asthenosphere

A natural concentration of minerals or rocks that can be mined at a profit is called a

ore

In the western U.S. the use of surface water is governed by the

prior appropriation doctrine

The minimum concentration necessary for profitable mining of an ore deposit depends on

the metal's average concentration in crustal rock, the price of the metal being recovered