Scenery is created by the deposition of rocks, the uplift of rocks, and the erosion of rocks. It is then modified by the vegetation that the  land supports.  Scenery can be broadly classified by the underlying geology

• Volcanic 

• Sandstone

• Metamorphic 

Eroded by 

• Fresh water 

• Ice

• Oceans

• Meteors

• Volcanic explosions

Leaving bare rock unless overgrown by 

• Evergreen forest

• Deciduous forest

• Tropical forest 

• Grassland 

• Ice

• Redeposited sand as beaches and silt ​

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Today's scenery is the latest snap shot of the  accumulation of multiple cycles of uplift and removal, dominated by the partial erosion of the last uplift. The erosion is mostly caused by liquid water creating "V shaped" valleys often following fault lines, and cliffs at the ocean. Glacier ice erodes creating "U- shaped" valleys. Secondary sources of erosion are wind, meteor impact, volcanic explosion. Where there is water, vegetation overgrows the rock. 

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Plate tectonics is the engine of change in our scenery. Volcanic activity leads to magma forming real time land growth mostly along plate boundaries such as the Cascades on the  "Ring of Fire" and at stationary hot spots such as Hawaii and Galapagos. 

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Sandstone is created from erosion debris settling out of the water. Uplift of sandstone from plate motion creates dry land that is then subject to water erosion to create places such as Zion, Grand Canyon and the Canadian Rockies. 

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Motion at plate boundaries also drive sandstone down towards the molten core. High pressure and temperature, and injections of magma causes chemical changes in sandstone to create metamorphic rock. Subsequent uplift from plate motion exposes the rock to erosion.  The youngest mountains such as the Sierras were uplifted 6-5My ago. The Himalayas and Rockies were uplifted  60My-40My ago. The Appalachians were uplifted 300My ago during the creation of Pangea. 

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The oldest rocks that are visible today are 4500My ago in western Australia, because Australia is in relative tectonic isolation. 

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UPLIFT

Uplift associated with tectonic plate boundaries creates the starting point for erosion.

Volcanism

Volcanism produces the most recent structures along the fault lines of the tectonic plates; 

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• Galapagos, Hawaii and Iceland are all "hot spot"  locations were you can observe the expulsion of liquid magma. 

• Cascade volcanoes are less than 2My old, and the highest peaks are less than 100Ky old. Beyond the eastern foothills is an arid plateau that was largely created 17My to 14My ago. 

• La Veta, the Spanish Peaks and all the other features, with few exceptions, were intruded as much as 10 km below the paleo surface that existed some 20-30 million years ago.  The processes of uplift, weathering and erosion since then have revealed what we see today.  All the features you see are referred to as “erosional remnants” because most of them are more resistant to weathering than the softer sedimentary rock they intruded. 

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Sandstone 

Sandstones and limestones are deposited in layers out of shallow seas. Away from the plate boundaries, the sandstone layers remain pristine. These are then uplifted and eroded to produce classic stair step valley walls.

• Zion was deposited 260 M (Kaibab) - 100 M years ago.  The upper half of Zion Canyon was carved between about 1 and 2 million years ago  with the Narrows  formed more recently.[27] There is a deep layer of white Navajo Sandstone.

• Escalente Staircase - White Pocket was 200-195My ago when White Navajo Sandstone was soaked in water and then subject to compression.  

• Monument  Valley was deposited in 300My - 270My ago. The floor is largely siltstone  deposited as silt by the meandering rivers that carved the valley over the last 2My. The mesa wall vivid red color comes from iron oxide exposed in the weathered "De Chelly" sandstone deposited 280My ago. The darker, blue-gray rocks in the valley get their color from manganese oxide.

• Grand Canyon was deposited  from 1.6B-270My ago have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted from  5 to 6 million years ago.

• Canadian Rockies were deposited 500My ago, and uplifted 80 and 55My ago from plate pressure analogous to pushing a rug on a hardwood floor the rug bunches up and forms wrinkles of unmodified sandstone with fossils. 

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Metamorphic 

Metamorphic rocks started as sandstones. Near plate boundaries, sandstones are driven down and magma injected in at high pressure creating new crystals structures. These rocks are typically much harder and resistant to erosion. As a result Metamorphic rocks form some of the steepest and most majestic mountains. Plutonic describes metamorphic rock that includes igneous rock formed by solidification of magma at considerable depth beneath the earth's surface. The granite igneous inclusions of  Yosemite in the metamorphic Sierra Nevada are an example. Metamorphic tectonite is a rock in which the fabric elements reflect the history of deformation, for example slate or slab.

• Sierra Nevada deposited  252My to 66My ago, uplifted less than 5My ago,  not long after the Sierra uplift began, ice ages started carving U-shaped valleys. The sheer walls and hanging valleys of Yosemite National Park are a product of this chilly past.

• Rocky Mountains were deposited  500My ago, the latest uplift between 80 and 55My ago.  In the  south, an unusual low angle subduction  produced the growth of the metamorphic Rocky Mountains in the United States, much farther inland than the normal 300 to 500 km.  Around 55My ago, the Rockies were like Tibet: a high plateau, probably 6,000 metres (20,000 ft) above sea level. Subsequent erosion stripped away the high rocks, revealing the ancestral rocks beneath, and forming the current landscape of the Rockies.  

• Appalachians first formed roughly 480 million years ago, uplifted 270My ago when Africa (Gondwana) plowed into Pangea to form mountains that stretched all the way from East US to Norway in Pangea. They once reached elevations similar to those of the Alps and the Rocky Mountains before experiencing natural erosion. It was not until the region was uplifted around 50My ago that the distinctive topography of the present was exposed.[19] Uplift rejuvenated the streams, which cleared deposits back to the 270My old structures. 

• Australia was deposited as 4500-2500My  rocks mostly in the west, 2500 to 538My  rocks in the center, and 538y to present rocks in the east. Down drive and uplift occurred due to plate movements in  Nuna, Rodinia and Pangea. Recent geologic events are confined to intraplate earthquakes, as the continent of Australia sits distant from the plate boundary. 

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REMOVAL

Water erosion

The flow of liquid water is probably makes the single biggest natural impact on our scenery. It flows downhill though any weakness in the rock forming anything from slot canyons to wide V-shaped valleys. In colder climes, ice flows much more slowly but is hard and abrasive. Glaciers from the ice ages 400Ky - 20Ky ago covered roughly half the globe creating U shaped valleys. Today's glaciers are receding due to global warning.  On the coast, ocean waves are another aggressive source of erosion. 

• Victoria Falls. 

• GC,

• Norway

• Cliffs

Meteor erosion to form craters

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• Meteor crater The object that excavated the crater was a nickel-iron meteorite about 50m (compared to 10km for the KT meteor) across created about 50,000 years ago when the local climate on the Colorado Plateau was much cooler and damper.[9][10] The area was an open grassland dotted with woodlands inhabited by mammoths and giant ground sloths 

• Chicxulub crater formed 66My ago by a 10km wide meteor was responsible for the extinction of the dinosaurs. 

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Volcanic explosion to form caldera

Caldera from volcanic explosion - Mt St Helens, Santorini, Yellowstone 

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• Mount St Helens is a explosion that occurred in 1982.

• Santorini island was the site of   the Minoan eruption (sometimes called the Thera eruption), which occurred about 3,600 years ago.  The eruption left a large caldera surrounded by volcanic ash deposits hundreds of metres deep.

• The Yellowstone Caldera, formed during the last of three supereruptions over the past 2.1M - 600K years, measures 70 by 45 km.