let disscuss importance of the earth science
HOW ROCKS ARE IDENTIFIED
A piece of rock taken as a sample of analysis, under a careful view, will reveal that it made of many ‘bits’ called grains. These grains range from a small size to the size of a house.
TYPES OF GRAINS
Grains may be minerals, pieces of rock or pieces of organisms called fossils.
A naturally occurring material composed of minerals, fragments of rock, or fossils. The chemical composition of a rock depends upon the minerals it has. The ways in which the mineral grains fitted together is the ‘texture’ of the rocks. Rocks also have larger scale feature, called structures.
These are naturally occurring inorganic compounds or elements.
The traces of organisms saved in rocks usually more than 10, 000 years old.
ELEMENTS, MOLECULES, AND COMPOUNDS of earth science
A collection of atoms of one kind called a chemical element.
Atoms combine together to form molecules. The Molecules of different chemical element join together made a compound.
Diamond is an element that contains an only carbon atom. Because of its purity, it is rare. Moreover, In the Earth’s crust carbon found in the molecule Calcium Carbonate CaCO3. The most common form of the Calcium Carbonate in the Earth’s crust is Calcite.
Atoms of a chemical element bonded like building blocks in the atomic structure. In Diamond, Carbon atoms bond from four directions that are why is so hard.
the world, chemical compounds do not occur in pure form and they have various shapes.
Inorganic compounds with a definite chemical composition, a definite atomic structure but physical properties that may vary with limits.
The physical property of chemical compound is color. Diamond and Calcite exist in different colors, because of traces lots of elements present in them.
IDENTIFICATION OF MINERALS
Following properties mostly used in identifying a mineral.
- Color which is because of chemical composition
- Cleavage the way they break depending on atomic structure
- Density how heavy they feel
- Luster that is surface appearance
- Powder color which is streak in the form of a scratch left on white tile
- Some react with acid are soluble or are magnetic
Crystallization is the process by which mineral identity takes place. Minerals formed in five ways.
- Crystallizing from molten rocks as it cools
- Recrystallizing due to heat
- it from evaporating water
- it is from liquids flowing through the pores in the rocks
- this from hot fluids that cool as they flow through rocks
Minerals in the rocks start melting at 600 C, nearly all the minerals in a rock have melted at 1800 C. The atoms and molecules in a rock are released to form a ‘bath’ of liquid called magma. Magma is usually less dense than rocks; therefore, it tends to rise. Magma crystallizes with a texture of random lock crystals. The rocks that formed from crystallizing from magma called igneous rocks.
Most magma crystallizes underground, but if magma flows out to the surface it called Lava. Solidified lavas are also igneous rocks.
MINERALS IN IGNEOUS ROCKS of earth science
Following minerals are found in igneous rocks.
However, the compound of silicon oxygen (SiO2) has bonded atomic structure. In igneous rocks, it has the gray color.
Silicon and oxygen (silicate) compound with extra aluminum and calcium. this has an atomic structure almost as much bonded as in quartz. However, it is off white, pink color in rocks.
Mica is also silicon and Oxygen compound but has poorly bonded in one direction atomic structure. That is why it has strong cleavage. This soft layered in the rocks in black or colorless.
The METAMORPHIC ROCKS
Under high temperature and great pressure, the minerals in a rock recrystallized without melting, the process called metamorphic. Moreover, in this process, minerals can change into new minerals. That crystallizes to form a tough rock called metamorphic rock.
Meanwhile, rock under pressure results in a rock that will have minerals in random direction locked.
Metamorphic under pressure in the roots of mountains, so, these cause minerals recrystallize at 90 C to the direction of the pressure and sheets/bands made in the rock.
The MINERALS IN METAMORPHIC ROCK of earth science
The minerals quartz, feldspar and mica also found in meta rock, but the Garnet is a silicate mineral that is most in meta rock. Because of hard pleasing red or pink colors, it considered in gem mineral.
The Marble made by the locking of calcite crystals as meta rock first made of caco3.