The hot material deep within the surface of the Earth melts to produce magma beneath the Pacific Plate. Each of the volcanoes in the Hawaiian island chain go through a series of stages in their lifetime. In short, the shield stage, postshield stage, erosional stage, rejuvenated stage, coral atoll stage, and the guyot stage. The shield stage is divided into three phases, the submarine, explosive, and subaerial. Following the gentle explosions of the pre shield stage, the submarine phase begins with pillow lava eruptions.
There are many caves though most are up on the cliffs on the island. A crater also exists in the middle of the island along with many smaller ones all over the place (Bahn and Flenley 1992:23). Just like the Hawaiian Islands, Easter Island exists over a hotspot. This means the earth’s plates are moving over a hole that leads from deeper in the planet. What this does is allow liquid rock, or magma, to come to the surface, thus creating islands.
00Earthquakes occur almost daily due to the fact that Costa Rica lies between two tectonic plates: the Carribean plate and the Coicos plate. These two plates push and shove each other causing small tremors throughout which can cause landslides,volcanic eruptions and once in a couple years, quakes with devastating results. The strongest earthquake recorded occurred in 1991 with a measure of 7.6 on the Richter scale. This earthquake left 4 dead and buildings as well as bridges and road were completely destroyed. If another Earthquake occurs, the coastal cities would be the most affected ones as they are closer to the plates.
The rocks are pebble to cobble sized basalt fragments. The samples collected ranged from 50mm to 120 mm. The rocks are angular. They have a gray, very fine ground mass. Fine plagioclase feldspars are visible throughout the ground mass and sparkle in the sunlight.
There are at least twenty seven known Votive Statues of Gudea. They originated from the Sumerian culture, one of the first known civilizations with documented history. The sculptures are sculpted from diorite, which is an igneous type of rock, though some of the earlier Votive Statues of Gudea were also carved from limestone and alabaster, but a majority use diorite as their choice of material. The diorite rock has a dark grayish complexion, though it can be seen as a greenish hue in certain lightings, giving the Votive Statues of Gudea an earthy presence to it.
Tsunamis happen when the plates on the crust of the earth move, therefore moving the entire plate so that the water rises and is pushed forward, therefore causing a tsunami (Drohan, 2009, p.21). These tectonic plates are everywhere, under everything from the biggest mountain to the smallest hill. Though it is infrequent, volcanoes have been known to cause tsunamis. It happens when to volcano begins to erupt, but instead of coming out from the top of the volcano a lateral blast shoots out from the side. Next, a quickly moving avalanche of lava pours into the water near it causing the wave to travel to distant coastlines (Springer, 2005).
Dinosaurs are the most successful of all terrestrial vertebrates. They dominated life on land for about 150 million years, which is the longest for any animal on Earth till date. Humans in comparison have been on earth for nearly, only 1 million years. Dinosaurs, owing to their gigantic size and uniqueness, have remained in the limelight since the discovery of it’s fossils. Scientists have studied and debated over it’s various characters.
*The dorsal surface of the carapace has a median row of five vertebral shields, two lateral rows of costal shields or a marginal row of twenty four or twenty five marginal shields. *There are six pairs of shields, overlying the plastron. *These shields are gular, humeral, pectoral, abdominal, femoral and anal. B) Endoskeleton – i) Skull – *The skull is heavy and strong without temporal opening (anapsid condition). * All the skull bones except the lower jaw and the hyoid bone are immovably united together.
However even more amazing is the fact that the time question is not yet solved. The main reason to this is because the fossils were not encased neither were they close to any foreign datable material. Making this even more difficult no singular organisms were, found close to the fossils that could be, used for dating. Inability to date the fossils from surrounding objects leaves only two options both of which raise the issue of accuracy. The radiocarbon dating method which could be done on the fossils is only accurate in fossils which are 50,000 years or younger.