Rocks and soils Rocks and soils Rock types

Rocks and soils

Rocks and soils • Rock types • Igneous rocks – Granite (žula) – Basalt (čadič) • Sedimentary rocks – – Coal (uhlie) Sandstone (pieskovec) Limestone (vápenec) Chalk (krieda) • Metamorpic rocks – Marble (mramor) – Slate (bridlica)

Rocks and soils • Rock structure • Resistance – Hard – Soft • Permeability – Permeable – impermeable • Landforms

Rocks and soils • Weathering • Physical weathering – Freeze-thatw – Exfoliation – Biological weathering • Chemical weathering – Limestone solution

Rocks and soils • Mass movement • • Rockfall Soil creep Mudflow Landslide

Rocks and soils • Mining and quarrying • Open-cast mining • Quarrying • Mining

Rocks and soils Soil profile Surface layer A horizon – humus content, organic activity B horizon – inwashing of nutrients C horizon – weathered parent material Parent rock

Rocks and soils Parent rock Time Topography SOIL Climate Flora and fauna

Rocks and soils • Soil types • Brown earths • Podsols • Tropical red earths

Rocks and soils • Brown earths • lowland areas • deciduous woodland • rapid recycling of nutrients and decay creates dark brown upper layer • chemical a biological weathering give a relatively deep and fertile soil

Rocks and soils • Podsols • higher wetter areas • coniferous forest • long time to decay • slower cycle or nutrients, • slow weathering of the parent rock • shallow soil • acidity and lack of humus - infertile

Rocks and soils • Tropical red earths • • continuous leaf fall thick litter layer, rapid decomposition, leaching of minerals, chemical weathering rapid decomposition of the bedrock deep soil, fertile soil unless the nutrient cycle is broken

Rocks and soils • Soil erosion • 400 years to form 1 cm of soil • 3000/12000 soil for farming • 11% of Earth´s surface - agricultural land • area of China + India - lost/50 y

Rocks and soils • Soil erosion • vegetation cover removed • deforestation • steep land • seasonal rainfall • removeal of hedgerows • overcultivation • overgrazing

Rocks and soils • Soil management - techniques • terracing • replacement of trees and hedges • contour farming • strip cultivation • bushes, windbreaks • mud and stone walls

Plate tectonics

Plate tectonics • Tectonic activity • • • Earthquakes and volcanic eruptions Earth´s crust, Mantle, Core Plates Continental (old and permanent) Oceanic (younger, constantly changing) Plate boundaries

Plate tectonics • Tectonic activity • Earthquakes and volcanic eruptions • Earth´s crust, Mantle, Core • Plates • Continental (old and permanent) • Oceanic (younger, constantly changing) • Plate boundaries core mantle crust

Plate tectonics • Earthquakes • distribution pattern • narrow belts • measured in Richter scale • each level 10 times stronger

Plate tectonics • Volcanoes • magma to the surface • increasing of pressure • accompanied by earthquakes • crater created • eruptions of steam and ash • most time inactive

Plate tectonics • Volcanoes • • landslide of rock, glacier ice and soil, mudflow blast waves of volcanic gas, steam and dust volcanic bombs poisonous gasses, floodwaters living organisms and forest destroyed electricity/telephone interrupted volcanic material - fertile soil

Plate tectonics Constructive margins Collision margins plate boundaries Conservative margins Destructive margins

Plate tectonics • Constructive margin • • • move away from each other magma rises new oceanic crust, the Atlantic Ocean widening by 3 cm/year new islands

Plate tectonics • Destructive margin • • • oceanic crust towards continental crust oceanic crust downwards it melts (heat and friction) severe earthquakes magma to the surface - volcanoes long chain of islands

Plate tectonics • Collision margin • • two continental plates move together cannot sink rocks are forced upwards fold mountains

Plate tectonics • Conservative margin • • plates slide past one another no crust created or destroyed no new landforms shockwaves cause earthquakes

Plate tectonics • Conservative margin • • plates slide past one another no crust created or destroyed no new landforms shockwaves cause earthquakes

Plate tectonics • Key words • Crater, poisonous gases, blast waves of volcanic gas, steam and dust, water temperature, rivers blocked, eruption of steam, landslide of rock, mudflow, explosion, cloud of fine ash, floodwaters, blast zone, setting dust, primary hazard, secondary hazards, prediction, monitoring, evacuation, resettlement, mudflow dams, fertile soil, epicentre,