CHAPTER 6. GEOLOGY AND MINERALOGY
One cannot fully understand life without understanding geology. One cannot understand fully the process of evolution without understanding the movement of plate tectonics. Geology is intimately related to evolution and ecology, certainly two of the most powerful forces affecting human development and history.
The authors have worked a great deal on the botany of the larger New York Metropolitan Region. In this regard the study of both zoology (including humans) and botany is greatly aided by the study of the geology of the area. Where biological species are located is not an accident but varies directly with the geology of the area. We have found that the more we understand the basic geology of the larger New York Metropolitan area, the more we understand the distribution of biological species. For instance, the Great Valley runs across the western edge of the larger New York Metropolitan area. Here one finds plants associated with limestone areas. This is good to know as it helps one understand why certain plants are found here that are not found in other areas of the region.
In discussing human history, we will later see how the earth's geology has had a massive effect on the political systems of the various nations of the world. We place political theory directly within an ecological context. And this certainly explains why a chapter needs to be devoted to geology.
This chapter was recently added and needs considerable work. That's what happens with a living book on the web.
Introduction to Mineralogy
There are some 2,500 different minerals.
Elements 92 of them;
Carbonates and Borates
Phosphates, Molybdates, Vanadates
uncombined; they have a shiny luster, are heavy, and have electrical conductivity; copper, silver, gold, lead, iron,
These have a metallic luster, but oxidize easily. Examples include arsenic, antimony, selenium.
Vanadates, chromates, molybdates, tungstates
calcite, dolomite, malachite, nitrates, borates, iodates
About 75 percent by weight of the earth's crust is composed of the two elements oxygen and silicon. For the most part, oxygen and silicon occur in combination with other abundant elements such as aluminum, iron, calcium, sodium, potassium, and magnesium to form an important group of minerals called the silicates. A single family of slicate minerals, the feldspars, comprises about one half of the material of the earth's crust.
Introduction to silicates (6 spatial arrangements)
1) tectosilicates -- quartz, microcline, orthoclase
2) phyllosilicates -- biotite, muscovite, serpentine
3) iniosilicates -- hornblende
4) cyclosilicates -- beryl, axinite
5) neosilicates -- olivine, zircon
6) neosilicates -- topaz
chalcedony -- composed of extremely small fibrous crystals of
Feldspars are the most abundant constituents of rocks, composing about 60 percent of the total weight of the earth's crust.
a) orthoclase or potassium feldspar group (the potassium aluminosilicates)
b) plagioclase group (aluminosilicates of sodium and calcium)
3) Mica group
Mica is a silicate mineral having sheet structure.
Muscovite mica -- colorless or pale-colored
biotite mica -- dark colored
4) Ferromagnesian minerals
Hornblende -- amphiboles
Augite -- pyroxene family
Garnet -- almandite
Thirty-Nine of the Two Hundred Common Minerals
garnet, olivine, augite, hornblende, tremolite, serpentine, muscovite, beotite, pyrite, galena, rock crystal, sulfur, copper, graphite, gypsum, halite, microcline, opal, jasper, agate
Atoms, Space Lattices and Crystals
There are thirty-two classes of crystals, but these are grouped into six systems.
6) cubic close packing or hexagonal close packing
soluble in water
soluble in dilute hydrochloric acid
soluble in warm dilute hydrochloric acid
soluble in warm dilute nitric acid
Mineral Forming Environments
magnetite, vesuvianite, tremolite, scapolite, chrysotele, kyanite, almadine, pyrite, staurolite, tremolite, dravite, talc, graphite, ciopside, wollastonite, dravite
labradorite, diamond, gabbro
typically dark; native iron, pyrrhotite
B. Granitic Minerals
molybdenite, granite, sodalite, syenite, corundum, cancrinite
A. Simple Pegmatite
beryl, almadine, muscovite, almadine, columbite, apatile,
B. Complex Pegmatite
muscovite, apatite, beryl, petalite, rose quartz
IV. Hydrothermal Environment
a hot, fluid residue, usually of magmatic origin, that is chiefly water that contains a rich supply of metallic elements
a) hypothermal -- great depth
millerite, pyrrhotite, nickeline, flourite
b) mesothermal -- shallow depths
gold, cinnabar, mercury, barite, calcite, dolomite, orthoclase, flourite, quartz, silver, hessite
V. Hydrothermal and Metamorphic Environments
Franklin-Sterling Hill area of New Jersey
VI. Oxidation and Secondary Enrichment Environment
Hypothermal or other near to air and water may oxidize. It is chiefly the metallic elements that oxidize.
galena, wulfenite, siderite, pyrite, smithsonite, adamite,
cupurite, azurite, malachite
b) secondary enrichment
VII. Evaporite Environment
a) alkalic collection
halite, trona, gypsum
b) borate collection
VIII. Volcanic (as in Paterson, NJ area)
Basalt area is coated with minerals. They are zeolites (chabazite, heulandite, mesolite, stilbite, and others). There are more than 60 species.
a) place minerals
gold, garnet, olivine, zircon, chromite, olivine, zircon, chromite
b) general collection
baurite, aragonite, magnesite, sulphur, flourite, calcite, dolomite, gypsum, galena, hematite, pyrite, hematite, manganite
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