TOPOGRAPHY ASSOCIATED WITH HORIZONTALLY LAYERE ROCKS TOPOGRAFIE GEASSOSIEER

TOPOGRAPHY ASSOCIATED WITH HORIZONTALLY LAYERE ROCKS TOPOGRAFIE GEASSOSIEER MET HORISONTAAL GELAAGDE GESTEENTES HILLY LANDSCAPES HEUWELAGTIGE LANDSKAPPE

INTRO Over time – rocks are laid down in several ways. Sediments collects in layers at the base of rivers, compressed en cemented together = SEDIMENTARY ROCKS. Once exposed = erosion modifies it to form solidified strata Oor tyd – rotse op verskeie maniere op die Aarde neergelê. Afsaksel in lae op bodem van riviere/mere en oseane, saamgepers en saamgesementeer = SEDIMENTêRE GESTEENTES. Wanneer blootgestel = erosiekragte verander vorm en vorm gestolde strata

CHARACTERISTICS AND PROCESSES ASSOCIATED WITH DEVELOPMENT OF HILLY LANDSCAPES EIENSKAPPE EN PROSESSE GEASSOSIEER MET ONTWIKKELING VAN HEUWELAGTIGE LANDSKAPPE Landscapes erode from original horizontal rock layers – depending on structure of rocks Alternating strata (resistant and less resistant strata) produce step-like valley slopes Hard layers = plateaus / cliffs Softer layers = erode quickly – gentle slopes. Landskap erodeer vanaf die oorspronklike horisontale rotslae – afhangende van die struktuur van die rotse. Wisselende lae/strata (bestande en minder bestande strata) bring trapvormige valleihange voort. Harde lae = plato’s of kranse Sagte lae = erodeer vinnig – skotige hange

CHARACTERISTICS AND PROCESSES ASSOCIATED WITH DEVELOPMENT OF HILLY LANDSCAPES EIENSKAPPE EN PROSESSE GEASSOSIEER MET ONTWIKKELING VAN HEUWELAGTIGE LANDSKAPPE Regions where rock strata are horizontally disposed – offer more/less equal resistance to erosion = hills with steep rounded slopes. Rounded slopes = typical in areas with high rainfall. e. G Valley of Thousand Hills in KZN / Ruens region of Caledon and Bredasdorp Streke waar rotslae horisontaal is – minder/meer gelyke weerstand teen erosie bied = heuwels met steil, geronde hange. Geronde hange = tipies van areas met hoër reënval. Bv Vallei van Duisend Heuwels in KZN / Rûens-streek van Caledon en Bredasdorp.

CHARACTERISTICS AND PROCESSES ASSOCIATED WITH DEVELOPMENT OF HILLY LANDSCAPES EIENSKAPPE EN PROSESSE GEASSOSIEER MET ONTWIKKELING VAN HEUWELAGTIGE LANDSKAPPE In arid and semi-arid regions – lack of water shapes a rugged angular landscape. e. G USA = badlands: badlands of Dakota Sneeuberge in Great Karoo also have badlands Ariede en halfariede streke – gebrek aan water vorm ruwe en hoekige landskappe. Bv. VSA = Dongavelde (badlands): dongavelde van Dakota. Sneeuberge in Groot Karoo het ook dongavelde

PROCESSES AND CHARACTERISTICS OF BASALTIC PLATEAUS EIENSKAPPE EN PROSESSE VAN BASALTPLATO’S Basaltic platieaus = high lying regions raised thousands of metres above the surroundings. Product of lava flow. Resulting rock = basalt and is dark, dense volcanic rock containing high amounts of silica. Basalt plato’s is groot hoogliggende streke – meters bo omgewing uitgelig is. Produk van lawavloei. Gesteente wat gevorm word is basalt en is donker, digte vulkaniese rots wat silika bevat.

PROCESSES AND CHARACTERISTICS OF BASALTIC PLATEAUS EIENSKAPPE EN PROSESSE VAN BASALTPLATO’S Plateaus are constantly carved away by erosion. Some are flat, others have been eroded away to form mesas, buttes or domes. e. G Columbia Plateau of NW USA, Lesotho Plateau and Deccan Plateau in India Plato’s word voortdurend deur erosie weggekalf. Sommige is plat en ander erodeer oor ‘n lang tydperk om mesas, spitskoppe of koepels te vorm. Bv. Columbia-plato in NW VSA, Lesotho Plato en Dekkan Plato in Indië

CANYON LANDSCAPES / LANDSKAPPE Canyon/gorge = steep ravine between cliffs carved out by down cutting action of a river. Layers of alternating hard and soft resistance are exposed by downward erosion. Freezing and expansion of water (physical weathering) also helps to form canyons Canyon/kloof = steil bergkloof tussen rotse wat deur ‘n rivier se afloop uitgekerf word. Lae met wisselende harde en sagte weerstand word deur die afwaartse erosie blootgestel. Vriesing en uitsetting van water (fisiese verwering) dra by tot die vorming van canyons