Ricardo Perez Historical Processes of Puerto Rico San Fermin Earthquake of 1918 The geological position of Puerto Rico raises a concern for earthquakes in the modern day. The island is located very close to the junction of the Caribbean and North American tectonic plates. A combination of seismic and volcanic activity created the Caribbean islands as we know them today. All of the Caribbean islands, with the exception of Barbados, were created from the fierce volcanic activity of the millions of years ago during the Antillean Revolution. Violent movements of the plates in the Post-Glacial era created the Puerto Rican Trench, nearly 24,000 feet deep, which is the deepest point in the Atlantic Ocean.
Discuss the view that the impact of earthquake hazards depends primarily on human factors [40] An earthquake is a tremor or shockwave in the earth’s crust that is caused by the sudden movement of the crust, resulting in the earth shaking. Most earthquakes are a consequence of tectonic plate movement by tension causing a sudden release of energy or rubbing. These normally occur at plate margins or along fault lines and can cause hazards which need to be prevented where possible. Earthquakes can therefore occur at all plate boundaries, destructive, constructive and conservative but the most damaging tend to happen at destructive margins where the earthquakes have a high magnitude due to the rubbing of the oceanic and continental crusts. A hazard is a natural event that has the potential to effect both life and property.
The earthquake began off of the north-eastern coast of Honshu and caused catastrophic damage. The coastal areas were hammered by a “series of large tsunami waves that devastated many coastal areas of the country, most notably in the Tōhoku region (northeastern Honshu)”. (“Japan Earthquake and Tsunami of 2011”, 1) According to Encyclopedia Britannica… The epicentre was located some 80 miles (130 km) east of the city of Sendai, Miyagi prefecture, and the focus occurred at a depth of 18.6 miles (about 30 km) below the floor of the western Pacific Ocean. The earthquake was caused by the rupture of a stretch of the subduction zone associated with the Japan Trench, which separates the Eurasian Plate from the subducting Pacific Plate. (Some geologists argue that this portion of the Eurasian Plate is actually a fragment of the North American Plate called the Okhotsk microplate.)
It increased by 7 ft a day.” Earthquakes You can predict when a volcano will erupt because you get earthquakes. This is because most volcanoes follow a regular pattern of increasing seismic activity as the eruption is about to take place, usually in the form of small earthquakes. Scientist use special equipment seismometers that tell and record earthquakes that happen underneath the volcano. Long period earthquakes- are beneath volcanoes and are believed that it is caused by magma moving through cracks that then shake the ground. Short period earthquakes- earthquakes under the volcanoes that is believed to be caused by rock breaking events Both types of
The force of one plate being dragged under another causes intense friction and the pressure increases. Eventually, there is so much pressure that the plates suddenly jolt, causing an earthquake. Where an oceanic plate meets a continental plate, sediments are thrust upwards. Due to the friction caused by the plates scraping against each other, the temperature in the mantle increases. Magma rises forming a long chain of volcanic fold mountains for example the Andes.
Movement in this fault zone resulted in the great Hanshin earthquake. A 30-50 km long rupture of a strike-slip fault occurred close to and under downtown Kobe. The eruption towards the north ruptured towards Kobe. The earthquake’s shallow depth of 16 km and close proximity to the built-up area meant that buildings and structures were subjected to much ground-shaking and soil liquefaction On Tuesday, January 17th 1995, at 5.46 am (local time), an unexpected earthquake of magnitude 7.2 on the Richter scale struck the Kobe region of south-central Japan, the shallow depth of the focus which was only about 16 kilometres below the surface and the fact that the epicentre occurred close to a very heavily populated area caused a great destruction. Seismic shockwaves travelled from Awaji Island (the epicentre) along the Nojima Fault to the cities of Kobe and Osaka.
Earthquakes are caused by the rift and abrupt movement of two rocks that suddenly slip past one another. Earthquakes occur along faults which are fractures in the lithosphere where sections of rock move past one another. There are three important parts to an earthquake: the focus, the epicenter, and seismic waves. The focus is the point on the fault where the separation occurs and from where the seismic waves are formed. The epicenter is located directly above the focus on the earth’s surface.
Cody Walters 11/29/1010 Math 144 Earthquake Intensity and the Richter Scale Earthquakes occur due to the activity of forces, energy, stored deep within the Earth's interior. These forces are constantly affecting the surface of the Earth, forming mountains, valleys, ridges etc. When the energy stored within the Earth is suddenly released, for example by shearing movements along faults in the crust of the Earth, an earthquake results. The area of the fault where the sudden rupture takes place is called the focus point or hypocenter. The point on the Earth's surface directly above the hypocenter is called the epicenter of the earthquake.
The earthquake occurred in the backarc region of the convergent boundary where the Pacific Plate subducted beneath the Eurasian Plate. The earthquake shaking caused moderately severe damage, VIII on the Mercalli scale. The jolting movement of the seabed made the water rise and fall, which set off a terrifying tsunami. The fast-moving waves spread in all directions. They hit Okushiri less than four minutes later.
Geology The Loma Earthquake 1989 Name Course Date due An earthquake is a physical occurrence where vibrations are caused by underlying rocks that are breaking under a lot of stress. The rocks are situated under the earth’s crust and are mostly caused when two tectonic plates come together, and pressure is created along the fault lines. It is then released towards the earth’s surface resulting in an earthquake. In 1989, the Loma Earthquake occurred in the region of the Santa Cruz Mountains that caused a total number of 63 fatalities, 3,557 injured related cases. It also destroyed a lot of property which is estimated to be about $6 billion.