Sample Test Questions Flashcards
Describe a volcanic eruption.
The mots violen volcanic eruptions happen at destructive pate boundaries or hot spots. Before an eruption magma and gases build up in the magma chamber. When the pressure become too great , the volcano erupts through a pipe called a vent , ejecting hot lava , gases , ash and rock pieces. These materials are know as pyroclasts. The top of the volcano be be blown off , the hole left is called a crater. Eg. Mount St.Helens 1980 eruption , Washington state , USA
Describe how an earthquake takes place.
Most major earthquakes happen at destructive plate boundaries. These too lates collide and over decades pressure builds p at a point called a fault line. When pressure becomes too great one plates slips releasing energy know as an earthquake. The point where energy is realised is called the focus. Energy radiates from all different directions, these are called shockwaves. Most damage is done in the epicentre , which is directly above the focus on the earths surface. When an earthquake occurs under the ocean it can cause a huge wave called a tsunami. Eg. Japan 2011 earthquake and tsunami.
Explain how fold mountains occur.
Folding occurs at destructive plate boundaries. Great pressure leads to extreme heat. This soften the layer of rock among them more bendable. Over millions of years, in a very slow process, the rock are pushed upwards and folded creating fold mountains. Te upward fold is called an anticline and the downward fold is called a syncline. An example of fold mountains are the Himalayans where the Indian and Eurasia plate collide
Explain the formation of one igneous rock.
Basalt is an igneous rock. It forms when magma comes out from a Locarno or fissure. The lava then cool quickly , as it is exposed to the elements ( wind , air , water) . It’s solidifies forming tiny crystals. Basalt is an extrusive igneous rock as is forms on the earths surface. It’s is found at the Gaints causeway in Co.Antrim . Basalt can be used for road chipping and construction.
Describe the formation of one sedimentary rock.
Limestone is a sedimentary rock. It is formed when layer of dead plants and animal build up on the ocean floor , meaning it is organic. Over millions of years the lower layers become compressed due to the weight of the layers above. This pressure compacted the layers and minerals like calcite , acted as cement to blend the layer together. Fossils can be found in limestone. The Burren in Co.Clare is a limestone region. Limestone is used in the construction industry , mainly for making cement.
Explain the formation of one metamorphic rock.
Marble is a metamorphic rock formed when limestone undergoes changes due to greta heat and pressure. The changes from heat alone is called thermal metamorphism. Heat from magma , reaches temperatures up to 2,000 degrees Celsius , changing the make-up of the rock it comes in contact with. Pure arable is white , while coloured varieties results from impurities. Green marble is found in Connemara Co.Galway. Marble is commonly used as a decorative stone in kitchen countertops and bathroom tiles
Describe two ways humans interact with the rock cycle.
Quarries supply various essential material for the construction industry , including sand , gravel , concrete , blocks and decorative stone like granite and sandstone. They also create employment , such as for truck drivers and engineers who manage extraction operation
