tectonics Flashcards
(4 cards)
Massive destruction by volcanic materials
Volcanic materials include lava, rock fragments, gases, & volcanic bombs which damage properties
Low silica lava flows quickly & over long distances causing damage to a large area
Pyroclastic flow destroys everything in its path with hot rock fragments ranging from ash to boulders at great speeds, more than 200m/s
Volcanic bombs of heated rocks can fall in areas surrounding the volcano causing damage to property, (homes & highways) e.g. ongoing eruption of Kilauea in Hawaii in 1983
Landslides occur due to structural collapse of a volcanic cone & may block roads, flood rivers, & burry villages & farmlands
E.g. eruption of Nevado del Ruiz in Andes Mountains in SA in 1985 released pyroclastic flow. The mixing of pyroclasts & glacial ice triggered lahars (wet volcanic debris) which engulfed the town of Amero & killed more than 20000 people
Distribution of mid-oceanic ridges
The mid-oceanic ridges are found in the middle of the Atlantic Ocean, where the mid-Atlantic ridge runs through North to South in the middle of the ocean.
A stretch of mid-oceanic ridges run from the Indian Ocean near Somalia, southwards into the Southern Ocean and extends towards the south and easter part of the Pacific Ocean
Fertile volcanic soil
Cooled volcanic lava has been weathered down to form highly fertile soil material, so farming communities continue to live near volcanoes to tap on increased economic revenue from the sale of surplus crops that are grown on the nutrient-rich volcanic soils. E.g. in Java & Bali, Indonesia, fertile volcanic soils are excellent for growing crops like tea, coffee, & rice. High crop yields enables the farmers to sell them to the local market or be exported for revenue & these two islands have been able to support a large rural population over many decades
Tourism
Interesting volcanic landform can lead to development of tourism industry, an important source of revenue. E.g. Mount Fuji in Japan, it’s symmetrical volcanic cone attracts tourists. Additionally, some volcanic areas are rich in history so people visit these areas to learn more
