Earth’s Lithosphere and Interior

Minerals, Magma, Non-sedimentary Rock and Plate Tectonics

Minerals and Magma

I. Composition of minerals

  1. Most ______have a number of different minerals in them, and come from cooled ______or altered ______.
  2. The element ______is the most common element found in the earth’s crust.
  3. Silicon is usually found bonded with ______in most minerals.
  4. The most common class of minerals contains the ______, the basis of which is the silicon-oxygen tetrahedra.

II. Rock-forming minerals

a. Oxides contain elements, often ______, and oxygen

b. Sulfides are usually metals and ______

c. Calcium Carbonates include ______

d. Ferrous minerals contain ______(Fe)

III. New York State Minerals

NYS minerals are often sedimentary rock minerals.

  1. ______-used as abrasives, found in metamorphic rock in Adirondacks
  2. ______, a silicate, found where ancient seas dried up in central/western NY
  3. ______and other salts, from deposits left by evaporating seas
  4. Wollastonite, an evaporite.

IV. The 5 properties of all minerals

  1. They are all ______
  1. All minerals have a basic ______, or orderly internal pattern of units
  2. All minerals have a definite ______, which means that their elements are always in the same ratio
  3. They are ______(do not come from living things or the remains of living things).
  4. They are ______, not anthropogenic

V. Mineral Identification (use with computer program)

  1. Luster- the manner in which the mineral ______in reflected light.

Metallic luster; the mineral looks like a metal

Non-metallic luster; anything that does not look like a mineral.

Ex. Pearly, earthy, dull, glassy

  1. Specific gravity- compares the density of the mineral to the density of water.
  2. Hardness is a measure of the minerals ______to being scratched.

Moh’s scale of ______compares minerals to each other. (talc is 1, ______is 10).

  1. Cleavage vs. fracture: description of the mineral’s tendency to break along definite angles and planes.

______describes clean, patterned breaks, while ______indicates a lack of pattern to the break.

  1. Streak- the color of the ______of a mineral, obtained from dragging it along an unglazed porcelain plate.
  2. Color- color is not always helpful, because one mineral may have trace amounts of metal and other impurities that will change the color.
  3. Other specific tests/indicators such as:

a. sulfur smells

b. calcite (CaCO3) ______even in weak ______

c. ______is magnetic

d. iron ______

e. halite tastes salty

f. flame tests can accurately identify minerals and elements

VI. Magma and mineral formation: hydrothermal vents article

Minerals that form from cooling magma form ______rocks.

Igneous rocks igneous pix

1. Igneous rocks are called ‘fire rocks’ because they form from ______or ______.

2. Magma is called ______because that is where the elements come together that will form minerals as magma cools.

3. Igneous rocks are called the ______of all others.

4. All igneous rocks have ______, because they form as the magma cools, and each crystal grows into the ones around them. Some crystals are so small that we can’t see this without the use of a ______.

5. Igneous rocks are classified (see page 6 of ESRT) according to:

a. the ______of the rock, which is determined by the magma or lava that forms the rock. As old rock pushes down into the mantle and melts, it mixes with magma that is already there, forming slightly different magma. Over time, different igneous rocks have formed. Minerals have different colors, and these colors help identify the type of igneous rock.

b. the ______or grain size of the rock, which is determined by how quickly or slowly the magma cools to form rock.

c. Together, mineral composition and texture identify the rock.

6. In the ______, the melting points for common igneous minerals are shown. Minerals with high melting points form crystals ______, while those with low (cool) melting points (typical of crust closer to the surface) forms crystals ______.

7. When the magma cools deep below the ground, it is called ______or plutonic, and the minerals formed will be ______grained.

When the magma cools NEAR the surface, much more ______, the crystals don’t have much time to form and the rock is called ______or volcanic, and the minerals will be ______grained. Glassy minerals form ______.

8. The three main igneous families, ______, ______and basaltic are described in the lab and lecture and text. The families are identified according to the type of ______from which they form, which are characterized by the minerals and color.

a. The GRANITE family, formed from ______magma, makes up the CONTINENTAL CRUST, which is low density (______) compared with the ocean crust (______).

b. The ______family, formed from ______magma, makes up the ocean crust. Its density explains why ______

c. The third family is the ______family, which comes from magma that is a mixture of both mafic and felsic minerals, therefore its minerals have characteristics of both granites and basalts.

9. Porphyritic textures refer to igneous rocks that have VARIOUS sized minerals, like a chocolate chip cookie. This happens when the magma ______in stages.

10. In summation, Igneous rocks are identified in the lab by comparing their:

______, which tells you what minerals are in it, and therefore what magma it came from and the ______, which indicates whether the rock cooled quickly or slowly (extrusive or intrusive).

VII. Metamorphic minerals have been changed by heat, pressure or chemicals.

Metamorphic Rocks are formed:

When magma ‘______s’ a nearby rock. (at volcanoes, mid-ocean ridges, intrusions)

At mid-ocean ridges when ______and sediments mix with hot gases

At ______boundaries when rock is ground and deformed

When mountains form by ______, compression

Overlying sediments exert so much ______they change the deep rock

1. These form when pre-existing rocks are ______due to heat and pressure.

(If the old rock melts, then it does not become metamorphic, because melted rock produces magma and igneous rock).

2. Metamorphic rocks are ______versions of pre-existing rock. The minerals often just line up differently. Intense metamorphism will really change the minerals, too.

3. Metamorphic rock are classified according to:

a. The presence or type of ______, which is seen by observing the texture of the rock. This must be observed in lab and using pictures.

b. The second identifier is the composition of the rock, especially when discussing the non-foliated rocks. For example, marble and quartzite look a lot alike, but are made of very different minerals. (the ______test identifies marble and a comparison of ______shows which is quartzite).

4. Rocks formed by intense pressure generally have the minerals align at a perpendicular to the direction of the pressure. This often forms the ______texture.

5. The type of foliation is described on page ______of the ______.

6. Rocks formed by intense heat are often called ______rocks because they are usually bands of rock that are ______due to the presence of nearby lava or magma flows, which partially ______the rock.

7. Contact metamorphic rock are found along igneous ______as the magma heats the rock. Zones of metamorphic rock usually are found between igneous rocks and other rocks.

8. Identifying metamorphic rocks is pretty tricky, and requires patience (and sometimes a good stereomicroscope)