Known As The Mangatepopo Valley example essay topic

Distribution: The manner in which phenomena are located within the environment; where things are located within an area. The Mangatepopo Valley is located on the North Western slope of Mount Ngauruhoe and on the South Western side of Mount Tongariro. A glacier formed the valley over 14,000 years ago that was eventually washed out leaving a terminal moraine and a lateral moraine on the left hand side. The glacier was formed by a build up of snow known as a cirque in South Crater, which eventually grew to occupy what is now known as the Mangatepopo Valley.

The valley has been in a continuous state of redevelopment this is through the constant eruptions of Mt Ngauruhoe sending lava flows down the valley, which have continued to re mould the land, and change the makeup of the soil. Added to this the lateral moraine is severely affected by climatic conditions such as Ice Heave which have the south facing side denude of vegetation and top soil. The Rang ipo Desert is found on the Eastern side of all three mountains, Ruapehu, Ngauruhoe and Tongariro. The desert was formed was formed by a pyroclastic flow from Taupo in the early AD's. This hot flow destroyed everything in its path and sterilizing a large area through the intense heat. The charred remains of the beech forest can be seen on the cuttings on the Desert Road.

The Tama Saddle the piece of land separating Ruapehu and Ngauruhoe is a funnel, which increases the wind speed by 20 - 30%, as the wind is unable to pass because of the two large masses either side and is forced though the narrow strip of land. Through the combination of Ice Heave / Hoar Frost which is present over 100 days of the year, the soil is lifted than taken away by the wind, known as aeolian erosion. Fluvial erosion is also present with over 1000 mm a year of rain hitting the desert, with very little and sparse vegetation the force of the drops hitting the earth are intense and make deep impact craters and gradually wash the topsoil away. The vegetation that is present is only able to hold onto a small amount the soil through their matted roots. Meanwhile the soil around these plants is taken away through aeolian and fluvial erosion. Through the continuation of the erosion pedestals are formed which can at times stand up to three metres tall.

But these do not last long as the erosional processes attack the sides and eventually collapse on themselves. Pinnacle Ridge is an example of topographical reversal. Pinnacle ridge is located on the Northern Ridge of Mt Ruapehu. Pinnacle Ridge used to be a valley that used to come off proto Ruapehu, and thousands of years ago several lava flows, flowed down the valley coating the valley floor in a solid impregnable floor. Over thousands of years the valley walls were eroded mainly due to tephra being highly susceptible to erosion. So slowly but surely the floor became even with the once steep sides and then eventually become taller than the once valley sides.

Until it lies where it is today a jagged lava coated ridge. The Crater Lake is situated on top of Mt Ruapehu, which is first in line of the three volcanoes of the Tongariro Volcanic Zone from a South to North Direction. The Crater Lake is there because is situated on an active vent. Over thousands of years and thousands of eruptions have caused a large explosion crater which ahs slowly filled up with water to what we know it as today. Examples of other explosion pits that have filled up with water are those of the Tama Lakes, which are located on the Tama Saddle. The Crater Lake is being fed by a number of ways the two main ones are; Snow melting of the glaciers near by, and by the rain that frequents the area.

The rain appears often because the mountains disrupt the airflow and displace a lot of air. The altitude at which Ruapehu is the mountain is prone to the cold winds that get colder the higher the point. So it is prone to rainfall known as orographic rainfall. Through the distribution which is the manner in which the phenomena are located, natural processes are interacting with or against the phenomena in some way, such as erosional processes aeolian or fluvial, or by volcanic..