Geology, Human & Environment

Verònica Morillas Fernández

Comunicació CientíficaMàster de Medi Ambient

Itinerari de Biologia8-03-10

HUMAN BEING: RESOURCES PREDATOR

• The human being obtains of the environment where he lives the natural resources necessary to satisfy his social needs.

• The resources that the nature provides to us are very varied: water, soil, rocks and minerals, air and the biological resources.

• These resources can be in use in his primary condition or, without transformations, be the first matters of a later process of production.

Water

• The water is fundamental for the life.• All the alive beings are formed by a changeable, but important

percentage, of water.• Hydrological cycle:

– Evaporation for the Sun – Perspiration of the plants– Rainfall– Infiltration – superficial Run-off

• Almost the whole water that supports the society comes from the continental waters (superficial and underground) that constitute 0,60% of the water of the planet. A great part cannot be exploited for which only he remains a 0,003% within reach of the human being.

• The soil is the most superficial layer of the lithosphere formed by the interaction of the climate and the alive beings on the rocky substratum.

• The factors that determine the formation of a soil are: the original rock, the climate, the topography, the organisms and the time.

• The characteristics of the soils determine the type of natural vegetation and the possibility of establishing cultivation.

Soil

Rocks and minerals

• Metallic minerals: to obtain metals of industrial use.

• Mineral and industrial rocks: to obtain non metallic substances, of industrial use or farming.

• Quarry rocks: to obtain constructive elements for the sector of the construction.

• Rocks and energy minerals: to obtain energy.

Alternative energies• Solar energy: the one that comes to the Earth in the shape of

radiations, is some 20000 times superior to the world consumption of energy. There is one of the alternative energies with more possibility of future.

• Hydraulic energy: the water has been in use as source of energy for a lot of time thanks to the water mills. It has had a paper very emphasized in the production of electricity.

• Wind power: the wind has been in use as source of energy in the windmills. Also they are in use for produce electrical energy.

• Nuclear power of merge: the union of light atomic cores, to form heavier others, liberates big quantities of energy.

• Geothermic energy: The internal heat of the Earth is the reason of the existence of warm waters of natural origin.

• The human being must apply methods and geological principles and of civil engineering to solve the problems derived from the works of architecture or of engineering that he realizes: construction of buildings, roads, railroads, ports, etc.

HUMAN CONSTRUCTS

ENVIRONMENTAL IMPACT

• Certain actions that we realize on the environment, as the exploitation of resources (water, soils, rocks, minerals, etc.) or the construction of works of architecture or engineering, endure changes in the quality of the environment, before, during and after the development of the action. These temporary variations in the environmental quality of a territory are called environmental impacts.

Environmental impact• Hydrological impact: derivate of the subtraction, the degradation or

the pollution of the superficial or underground waters.• Soil impact: because of the subtraction, the degradation or the

pollution of the soils.• Geologic impact: as result of the subtraction or the addition of rocks

and minerals, of changes in the dynamics of erosion and sedimentation, etc.

• Geotechnical impact: as result of the alteration of the physical properties of the area because of movements of lands, of refilling quarries with residues, etc.

• Atmospheric impact: because of the atmospheric pollution produced by engines of combustion, burning of different substances, accidental leaks, etc.

• Climatic impact: derivative of the liberation of gaseous substances that could modify the climate: greenhouse gases, gases that destroy the ozone layer, etc.

• Sonorous impact: provoked by noises and vibrations.• Ecological impact: as a result of the degradation of the ecosystems:

loss of biodiversity and habitats, alteration of the relations between the different alive beings and the environment where they live, etc.

• Landscape impact: because of the loss of aesthetic visual quality.• Socioeconomic impact: as result of the social and economic

modifications produced: changes in the location of a village after have been flooded by the waters of a reservoir, negative impact on the tourism by the extractives activities of a quarry, improvement in the communications with the construction of a highway, etc.

Environmental impact

GEOLOGIC RISKS• Coexist with the nature and exploit the natural resources

endures a risk that sometimes can turn in a catastrophe.• The constituents and geologic processes are the reason of

many natural catastrophes. • We cannot eliminate the reasons that produce the geological

risks, but we can minimize the effects:– The prediction consists of knowing with accuracy where, when and

how a geological risk will be produced; its location in the space and time, its intensity and its development.

– The prevention is the set of measures that are adopted by the purpose of minimizing the damages that a geological risk could produce.

• Some geological constituents, rocks and minerals, are the reason of geological risks. The risks derived from these constituents appear slowly and they not provoke catastrophes of great magnitude.

• The expansive soils are those that experience continuous changes of volume according to the content in water. This happens when there is the presence of a high percentage of expansive clays.

Constituents

• Earthquake: consists of the sudden liberation of energy that propagates by seismic waves. The point where it originates is called hypocenter. The liberated energy is measured by the magnitude.

• Volcanic eruptions: consist in the process of emission of volcanic materials to the Earth's surface. They are classified by the eruptive mechanism.

• Hillside instability: are movements caused by direct action of gravity, displacing volumes of rocks or snow. They are natural processes or human-induced and affect the artificial slope.

Geologic processes

• Subsidence: It’s a vertical movement of the Earth's surface respect to its previous level. It’s a fast and sudden movement.

• Floods: it’s any process that covers of water a land that is usually dry. It’s the geological risk that produces more damage.

• Promenade risks: the coastal zones suffer diverse geological risks originated by the processes that come together in these spaces. This risks are tsunamis, erosion and sedimentation processes, coastal floods, etc.

Geologic processes