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Whole Lotta Shakin' Goin' On

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www.PDHcenter.com 9/23/2015 Whole Lotta Shakin’ Goin’ On Table of Contents Slide/s Part Description 1N/ATitle 2 N/A Table of Contents 3~108 1 Know Your Enemy 109~199 2 Predicting the Future 200~323 3 The Land of Fruit & Nuts 324~451 4 The Big One 452~584 5 How Safe? 585~626 6 The Jesuit Science 627~704 7 The Waiting Game 705~827 8 Quake-Proof Construction 828~961 9 The Delicate Balance 962~1000 10 Out of This World A History of Seismicity 1 2 Part 1 Since Ancient Times Know Your Enemy 3 4 “…Several cataclysmic events re- ported in the Old Testament may have been connected with earth- quakes, according to two scien- tists who have found tentative ev- idence of a fault line in the Holy “…Since ancient times man has wondered at earthquakes. Land. Geophysics Prof. Amos Nur of Stanford and geologist Ze’ev According to one primitive belief, the earth was disk-shaped Reches of Israel’s Weizmann In- and rested on the horns of an enormous bull. In turn, the bull stitute said frequent earthquakes balanced ppyrecariously on a largeegg which lay on the back may have occurred along the of a giant fish. When the bull was pestered by cosmological north-south ground fracture over insects, he shook his head or wiggled an ear – thus causing the past several thousand years, including major events every two earthquakes…” centuries or so. The last such Popular Mechanics, October 1939 quake shook the area July 11, 1927, measuring 6.5 on the Richter scale…” Popular Mechanics, September 1979 Left: caption: “The Jericho Earthquake 5 of 11 July 1927 (Isoseismic Map 6 in Sieberg Mercalli Scale)” © J.M. Syken 1 www.PDHcenter.com 9/23/2015 Above: caption: “The earth- quake of July 11, 1927. Sha- ttered remains of St. John’s Convent at the Jordan. A complete ruin.” “…‘It is very likely that the collapse of the walls of Jericho, under Joshua’s siege, Left: caption: “A house in was caused by an earthquake similar to the 1927 event,’ the investigators re- Nablus reduced to a mere ported. The fault, they said, passes about five miles east of Jericho. ‘Aside from shell by the earthquake of proximity of the fault, there is a remarkable similarity between the (biblical) description of the river-flow cutoff, and the damming of the Jordan River by July 11, 1927” 7 earthquake-induced mud-slides observed during the past millenium’…” 8 Popular Mechanics, September 1979 To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture, click Options in the Message Bar, and then click Enable external content. The Beirut Earthquake of 551 occurred on July 9th 551 A.D. It had an estimated magnitude of about 7.6 on the Moment Magnitude Scale and a maximum felt intensity of X (Intense) on the Mercalli Intensity Scale (MIS). It triggered a dev- astating tsunami which affected the coastal towns of Byzantine Phoenicia, causing great destruction; sinking many ships and killing large numbers of people. One estimate by Antoninus of Piacenza for Beirut alone was 30K dead as a result of the temblor and ensuing tsunami. “…Nur and Reches also said it was likely that Sodom and Gomorrah, east of Jericho, fell into ruin during another earth- quake some 4,000 years ago…” 9 10 Popular Mechanics, September 1979 To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture, click Options in the Message Bar, and then click Enable external content. To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture, click Options in the Message Bar, and then click Enable external content. The Crete Earthquake of 1303 occurred at dawn on August 8th 1303. It had an estimated magnitude of about 8, a maximum intensity of IX (Violent) on the MIS and triggered a major tsunami that caused severe damage and loss of life on the island of Crete and in Alexandria, Egypt. The MIS is a seismic scale used for measuring the intensity of an earthquake. It measures the effects of an earthquake and is distinct from the Moment Magnitude Scale usually reported for an earthquake (sometimes mis- reported as the “Richter Magnitude”), which is a measure of the energy released. The intensity of an earthquake is not totally determined by its magnitude; it is not based on first physical principles but is, instead, empirically based on observed effects. The MIS quantifies the effects of an earthquake on the Earth’s surface, human beings, objects of nature and man-made structures on a scale from I (not felt) to XII (total de- In 1902, the ten-degree MIS was expanded to twelve degrees by Italian struction). Values depend upon the distance to the earthquake (with the physicist Adolfo Cancani. It was later completely re-written by the German highest intensities being around the epicentral area). Data gathered from geophysicist August Heinrich Sieberg and became known as the Mercalli– people who have experienced the quake are used to determine an inten- Cancani–Sieberg (MCS) scale. The MCS scale was later modified and sity value for their location. Between 1884 and 1906, the Italian volcan- published in English by Harry O. Wood and Frank Neumann in 1931 as ologist Giuseppe Mercalli revised the widely used, simple ten-deg- the Mercalli–Wood–Neumann (MWN) scale. It was later improved by Cha- ree Rossi–Forel Scale, creating the MIS, which is still in use today. rles Richter, the father of the Richter Magnitude Scale (RMS). The scale is 11 known today as the Modified Mercalli (MM) scale (above) or Mod- 12 ified Mercalli Intensity scale (MMI). © J.M. Syken 2 www.PDHcenter.com 9/23/2015 To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture, click Options in the Message Bar, and then click Enable external content. The Environmental Seismic Intensity scale (ESI) is a seismic scale used for measuring the intensity of an earthquake on the basis of the effects of the earthquake on the natural environment (Earthquake Environmental Effects or EEE). The international effort to develop a new scale of macroseismic intensity that would focus exclusively on environmental effects of earthquakes began in the early 1990s and was sponsored by the International Union for Quaternary Research (INQUA). After the final draft of the scale was approved by INQUA at its XVII Congress in Cairns, Australia (in 2007), the scale became officially known as “ESI 2007.” Like many other intensity scales, ESI 2007 uses the basic structure of twelve degrees of seismic intensity and is designed for application during field surveys immediately after the seismic event. However, the definitions of intensity degrees in ESI 2007 are based on the observation of distribution and size of environmental effects produced by an earth- quake. This approach makes ESI 2007 a unique diagnostic tool for the assessment of seismic intensity levels X to XII in sparsely populated and uninhibited areas where earthquake effects on people and built environ- ment may not be easily observed. For intensity level IX and lower, the ESI 2007 scale is intended to be used as a supplement to other intensity scales. 13 14 To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture, click Options in the Message Bar, and then click Enable external content. “It was in this country impossible to keep upon our legs, or in The Earthquake of 1343 struck one place on the dancing Earth; nay, those that lay along on the Tyrrhenian Sea and Bay of the ground, were tossed from side-to-side, as if on a rolling Naples on November 25th 1343. billow.” Underground shocks were felt Vincentius Bonajutus in Naples and caused signif- RE: contemporary account of the Sicily Earthquake of 1693 which struck icant damage and loss of life. Of parts of southern Italy near Sicily, Calabria and Malta on January 11th 1693 major note was a tsunami cre- at 9:00 p.m. This earthquake was preceded by a damaging foreshock on ated by the earthquake which January 9th. It had an estimated magnitude of 7.4 on the Moment Mag- destroyed many ships in Naples nitude Scale (the most powerful in Italian history) and a maximum inten- and destroyed many ports along sity of XI (Extreme) on the MIS, destroying at least seventy towns and the Amalfi Coast, including Am- cities, seriously affecting an area of 2,200 square miles and causing the alfi itself. The effects of the tsu- death of about 60K people. The earthquake was followed by tsunamis that nami were observed by the devastated the coastal villages on the Ionian Sea and in the Straits of poet Petrarch, whose ship was Messina. Almost two thirds of the entire population of Catania were killed. forced to return to port and The epicenter of the disaster was probably close to the coast, possibly recorded in the fifth book of offshore, although the exact position remains unknown. The extent and his Epistolae familiares. degree of destruction caused by the earthquake resulted in extensive 15 rebuilding of the towns and cities of southeastern Sicily. 16 A Better Understanding 17 18 © J.M. Syken 3 www.PDHcenter.com 9/23/2015 “…Probably the most important work that has been done in the observation of the causes and nature of earthquakes has been accomplished since the beginning of the twentieth century.
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