GEOLOGY

Geology is the study of the

earth, its processes, its

materials, its history, and its

effects on humans and life in

general.

Crust

Crust

Crust

Mantle

Mantle

Mantle

Nucleus

core

Nucleus core

Internal

parts of

the

Earth.

Concepts:

Rock:

It’s a lump or mass of hard

consolidated mineral matter.

Sedimentation:

The phenomenon of sediment or

gravel accumulating.

Sediment:

Particles that form a sedimentary

rock by accumulating.

Erosion:

Is the process by which

material is removed from a one

place to another.

Agent of erosion:

wind, moving water, moving ice

and gravity.

TYPES OF

ROCKS

Igneous rocks:

Are called fire rocks and are

formed either underground or

above the ground.

They are formed when

volcanoes erupt causing the

magma to rise above the

Earth surface, this lava form

them when it’s cold.

volcano

IGNEOUS

ROCKS

ANDESITE

Grey, with black and white flecks

DUNITE

• Green, rock form of olive

(Phanerictic and intrusive)

RHYDILE

• Light, sandy and pinkish (Aphanitic

and extrusive)

PUMICE

• Tan and Gray, small pores (Vesicular and

extrusive)

SCORIA

• Almost back, bubbly (Vesicular and

extrusive)

OBSIDIAN

• Glassy, red and black

BASAT

• Dark, black

PEGMATITE

• Large, white crystals

(Phanerictic and intrusive)

GABBRO

• Darker, fewer white spots

(Phanerictic and intrusive)

GRANITE

Light, colored (Phanerictic and

intrusive)

GRANITE PORPHYRY

Pink and Grey (Porphyritic and

intrusive)

DIORITE

Light, peppered with white (Phanerictic

and intrusive)

DIORITE

Metamorphic rocks:

It’s the transformation of an

existing rock type, in a

process called metamorphism

which means change in form.

These rocks were once

igneous or sedimentary rocks.

The rocks are under tons of

pressure and this causes them

to change.

They are subjected to high

pressures (about 1,500 bar),

high temperatures (between

150 and 200 ° C) or a working

fluid that causes changes in

the rock composition,

adding new substances to it.

Metamorphic rocks are

classified according to

their physicochemical properties.

Metamorphic rocks are classified

in two kinds according with their

textures: foliated and non

foliated.

Foliated texture:

Some of them are

the slate (breaking

are obtained

sheets) the shale

(breaks easily), and

gneiss (composed

of light and

dark minerals).

Non foliated texture:

Some of them

are marble (crystalline

appearance and are

formed by

metamorphism of

limestone and

dolomite), quartzite

(is white but can be

changed by impurities)

METAMORPHIC ROCKS

TWO TEXTURES FOLICITED AND

NON-FOCILIATED

QUARTIZITE

• White, tan , or reddish-brown, granny (Non.foliated).

METACONGLOMERATE

White quartz crystals handing together gray

particles (Non- foliated)

MARBLE

• Pink, but not always (Non-

foliated)

GNEISS

• Black and white layering, slight glitter

(Foliated)

SCHIST

• Glittery mica (Foliated)

PHYLLITE

• Brown/ orangish sheen of mica

particles (Foliated)

SLATE

• Layered, dark gray / black , flat (Foliated)

Sedimentary rocks:

It’s a type of rock formed by

sedimentation of material at

the Earth surface and within

bodies of water.

They may be formed on the

banks of rivers, deep ravines,

valleys, lakes, seas, and at the

mouths of rivers. Are arranged

in layers or strata.

sedimentary rocks are rocks formed

by accumulation of sediment,

subjected to physical and chemical

processes (diagenesis), result

in more or less consolidated

material of a certain consistency.

SEDIMENTARY ROCKS

TWO TEXTURES, CLASTIC

AND NON-CLASTIC

CHERT

• Multicolor, possibly swirl (Non-clastic)

OOLITIC LIMESTONE

• Off color grains “EEW” (Non-

calstic)

COAL

• Black, akin to charcoal

(Non.clastic)

DOLOSTONE

• Mostly uniform in color, smooth (Non-clastic)

COQUINA

• Little shell fragments

(Non – clastic)SHALE

• Gray and flat (Clastic)

SANDSTONE

• Red , brow, or tan, sandy looking

(Clastic)

ARKOSE

• 20% pink feldspar (Clastic)

QUARTZ- PEBBLE

• (Conglomerate)

• Milky white pebbles (Clastic)

FOSSILIFEROUS LIMESTONE

• Full of “fossils” (Non- clastic)

The fundamental division

of sedimentary rocks is done

taking into account the

predominant form of deposit or

sediment occurs:

1. Detrital: in that

sedimentation takes

place by decreasing

energy transportable

agent. The sediment is

called Detrital or Clastic.

2. Chemicals: the deposition is

produced either by

concentration, such as

evaporation of solvent or super

saturation of the solution or

by precipitation, which occurs

when a chemical reaction with

formation of insoluble. In this

case the deposit is

called chemical.

3. Organic: when they

accumulate in the

sedimentation plant or

animal remains, producing

an organic deposit.

BASALT

Compiled Material by:

ArchitectCarlos Eduardo Osorio Villabona