Saturday, February 5, 2011

The Island of South America – Part III

Continuing from the last two posts with the comments sent to me by a friend regarding statements made by a Baja Peninsula theorists, the next point the theorist makes is:

6. “Think about recent catastrophes: Mt. Saint Helens, San Francisco earthquake, New Orleans hurricane, Indonesia tsunami, Krakatoa, etc. All of these are extreme catastrophes definitely changed the "face of the land" and many people where killed but the people who survived where still able to recognize the landforms around them.”

Triggered by a 5.1 earthquake, the lateral blast of Mt. Saint Helens took place in less than a minute, moving some 1300 feet of earth over a 230-mile fan-shaped area of devastation reaching a distance of 17 miles from the crater in just over 4 minutes. Temperatures rose to 660º F. and the power of 24 megatons of thermal energy. The largest landslide in recorded history swept down the mountain at speeds of 70 to 150 miles per hour and buried the North Fork of the Toutle River under an average of 150 feet of debris. Some areas were covered by as much as 600 feet. In all, approximately 23 square miles of material was removed from the mountain, and pyroclastic flows rolled out of the crater for about 9 hours after the eruption, covering 6 square miles at temperatures of nearly 1300º F. However, the extent of the total devastation of the blast and earthquake lasted barely over four minutes.

The 7.7 to 8.2 San Francisco earthquake, which killed 3,000 people and injured 225,000, ranks as one of the most significant earthquakes of all time, lasted between 45 and 60 seconds, and was felt from southern Oregon to south of Los Angeles and inland as far as central Nevada. Rupturing the northernmost 296 miles of the San Andreas Fault from northwest of San Juan Bautista to the triple junction at Cape Mendocino, the earthquake tore open the ground for 270 miles along the San Andreas rift. Most of the earthquakes damage was from the resulting fires from ruptured gas lines.
The Category 3 hurricane Katrina that hit New Orleans did damage, but most of the destruction occurred from the breaches in 50 drainage and navigational canal levees which flooded about 80% of the city, with water rising as high as 15 feet. 1,464 people died. Actually, Katrina was nowhere near as devastating as the category 4 storm and hurricane that hit Galveston Island, Texas, in 1900, killing between 6,000 and 12,000 people (official estimates place the number at 8,000). More people died in that hurricane than all the hurricanes to strike the U.S. since. The mercurial barometer showed a steady decline on the barograph for 1 hour and 20 minutes covering the intensity of the storm, and waters rose to as high as 15 feet across the island for another 1 hour and 10 minutes. Three thousand homes, half of Galveston’s residence portion had been swept away.

The recent tsunami that hit Indonesia—the world’s larges archipelago located on the Pacific Ring of Fire (a series of fault lines stretching from the western Hemisphere through Japan and Southeast Asia—was from an underwater 7.7 (some claim 9.0) earthquake on Sumatra island's coast. The monster Indian Ocean tsunami killed 230,000 people in a dozen countries.

The eruption of Krakatoa in the Sunda Islands of Indonesia, in 1883, lasted for 2 ½ days, however, the initial eruption which did all the damage lasted from about 1 ½ days. The island exploded, officially killing 36,417 people (though some estimates are as high as 120,000).
The explosion, which registered 6 on the VEI, and was equivalent of 200 megatons of TNT, about 13 times greater than the nuclear yield of the bomb that devastated Hiroshima, Japan, and four times greater than the largest nuclear device ever detonated, is still considered to be the loudest sound ever heard in modern history, with reports of it being heard nearly 3,000 miles from its point of origin. The shock wave from the explosion was recorded on barographs around the globe, and wiped out 2/3 of the entire island, leaving only 30% to view. 165 villages were destroyed and 132 seriously damaged, with 21,00 killed by the blast, and another 21,000 from the following tsunami.

It is interesting that Rosenvall includes Krakatoa in his list of “surface” catastrophes that did not change the face of the earth, for most of the island of Krakatoa disappeared, and the two other nearby islands lost much of their size. Four islands have since risen in the area, but three disappeared within a couple of years, though the fourth, Anak Krakatau (Child of Krakatoa) has remained, producing lava flows faster than the waves could erode them.

(See the next post, “The Island of South America Part IV,” for the reason why these modern-day cataclysms did not change the face of the earth like described in the Land of Promise in 3 Nephi)

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