At four minutes past one on the afternoon of July 11, 1927, a strong earthquake shook the town of Jericho in the Holy Land, causing cracks and fissures in buildings and the ground, and great panic among its people. The shaking was not confined to Jericho itself: many cities and villages in Judea, Samaria, and Galilee suffered as well.
The earthquake was large enough to be recorded at seismological stations then in existence in Europe, South Africa, North America, and the USSR. Although these records were few, they were sufficient to provide accurate arrival times for the compressional waves generated by the earthquake. From these seismologists could determine the quake’s epicentre – the point at which the earthquake rupture motion began – its time of origin and its magnitude. The epicentre was next to the Jordan river about 15 kilometres north of Jericho, under the plain which extends north of the Dead Sea. The amplitude of the recorded seismic waves indicated an earthquake of about 6.5 on the Richter scale.
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The 1927 earthquake at Jericho was followed by a series of aftershocks, many of which were also strong enough for their epicentres to be located. These aftershocks cluster along a line through the origin of the main shock and continue south into the Dead Sea, suggesting that land along the fault slipped to make the quakes run approximately from north to south within the trough drained by the Jordan river. Analysis of the seismic records using modern methods has confirmed this hypothesis and specified further details of the motion across the fault: the land mass on the east side moved north, whereas the land mass on the west moved south during the earthquake by perhaps as much as 50 centimetres.
This result fits other information supplied by geologists and geophysicists; the Jordan rift, together with the Gulf of Eilat to the south and the Bekaa region to the north, forms the boundary between the Arabian plate to the east, and the African-Sinai plate to the west (see map). According to the theory of plate tectonics, which describes movements of plates of the Earth’s crust, Arabia is moving north as the Red Sea opens in the south, and is colliding with Asia to produce the Zagros mountain belt in Iran. The Arabian plate moves northward relative to the African-Sinai plate at 0.5 to 1 centimetre per year. The 1927 earthquake is the only sizable event along this fault to have been recorded on instruments. It was only moderate in size and cannot alone be said to represent the long-term pattern of fault motion that plate tectonics predicts. But from this area we also have the historical, biblical and archaeological evidence. Unlike any other place on Earth, the historical record here extends back about 10 000 years. By comparing this record with the effects of the modern earthquake, we may infer a great deal about seismic activity in the Jericho region.
An attentive observer can easily follow the Jericho fault along the Jordan plain: it disrupts the flat sediments and there is a line of springs along it. During the 1927 earthquake, the ground cracked in several places and water poured out; this phenomenon, caused by soil liquefaction, is common in earthquakes elsewhere. The pressure changes underground can change a wet, yet coherent soil or mud into a fluid that flows and can burst out onto the surface during the quake. In other cases, the water squeezes out of the soil as springs.
During the 1927 quake, chunks of mud slid into the River Jordan near Damiya, about 40 kilometres north of Jericho, temporarily reducing its flow. The quakes and their associated phenomena destroyed numerous buildings in Jericho, and caused lesser damage that was remarkably similar to the damage inferred from historical descriptions of past earthquakes. There have been about 30 earthquakes with a similar destruction pattern in this area during the past 2000 years or so (as summarised in the Table).
The awesome fortification of Masada in the Judean desert towers over the Dead Sea. It served as the last Jewish stronghold against the Roman armies until AD 73, when its 960 inhabitants committed mass suicide after surviving a prolonged siege. The conquering Roman army breached the citadel, but an earthquake along the Jericho fault in 363 was probably responsible for the final destruction of Masada. The ruins show that the storehouse walls apparently collapsed as a single unit; this is the pattern of destruction caused by an earthquake, rather than people.
In 31 BC, a major upheaval on the Jericho fault destroyed the town of Qumran, where the Dead Sea scrolls were found a few decades ago. A remarkable and detailed description of this event appears in the writing of the Jewish historian Josephus. ‘At this time it was that the fight happened at Actium between Octavius Caesar and Anthony in the seventh year of the reign of Herod and it was also that there was an earthquake in Judea, such a one as has not happened at any other time and which earthquake brought a great destruction to the cattle in that country. About 10 000 men also perished by the fall of houses, but the army which lodged in the field recorded no damage by this sad accident.’ (Antiquities of the Jews, Book XV, chapter 5, verse 2).
——————————————————— Earthquakes on the Jericho fault for which there is historical documentation. ——————————————————— Year Recorded damage ——————————————————— BC 117 Earthquakes 64 Earthquakes 31 The year of the battle of Actium. Destruction of Kumran on the west bank of the Dead Sea. AD 30 Earthquakes 48 Earthquakes 315 Earthquakes 362 Damage to the Temple area in Jerusalem, some work-men killed. Destruction of Arepolis (the biblical Rabbat Moab, today Khirbe-en-Robbe) and Kir-Moab (El Kerak). Tsunami in the Dead Sea. 637 Earthquakes 641 Earthquakes 600 Destruction in Jericho and vicinity. Monastery of St Euthymus destroyed. 710 Jerusalem. Damage to Al-Aqsa mosque. 746 Great damage in Jerusalem and to monasteries north of the Dead Sea. 756 Damage to the Temple area in Jerusalem. 765 Damage to Al-Aqsa mosque, Jerusalem. 777 Earthquakes 802 Earthquakes 1002 Earthquakes 1016 Earthquakes 1033 Jericho destroyed, damage to Jerusalem. 1060 Destruction of St John’s monastery near Jericho (rebuilt in 1180). Monastery of Mar Elias in the Judean desert seriously damaged. 1267 A stoppage of the Jordan river at flood time 1534 Jerusalem – the tower of the Holy
Sepulchre collapsed. 1546 Tsunami in the Dead Sea. Waters of the Jordan River cut off for two days by a landslide of Lisan marls above today’s Damiya bridge. Damage and casualties in Jerusalem. Destruction and victims in Nablus and Hebron. Damage in Ramle, Gaza, Kerak, Salt. Tremors felt in Damascus. 1834 Damage in Jerusalem, Bethlehem and Mar Saba. Large blocks of asphalt floating on the Dead Sea. 1859 Damage in Jerusalem. 1863 Earthquakes 1864 Earthquakes 1868 Earthquakes 1900 Earthquakes 1903 Northern Judean hills. Damage area spread from Jenin to Bethlehem, especially severe at Nablus. 1906 Stoppage of the Jordan river near Jericho for 24 hours. 1927 15 kilometres north of Jericho,
magnitude 6.5.Many aftershocks (1928-1930) ————————————————————-
Josephus further details the consequent rupture of the central water cistern in Qumran, which forced the inhabitants to abandon the town for several decades. The 2000-year-old fault rupture in the stairs of the cistern, unearthed by archaeologists some years ago, appears as fresh as if it had happened yesterday.
Going further back in time, the Bible records Zechariah’s prophecy, based upon the description of a large earthquake which occurred during the reign of King Uzziah around 760 BC: ‘ . . . and the Mount of Olives shall cleave in the midst thereof toward the east and toward the west, and there shall be a very great valley; and half of the mountain shall remove toward the north, and half of it toward the south. And ye shall flee . . . like as ye fled from before the earthquake in the days of Uzziah king of Judah’ (Zechariah, ch 14 v 4-5).
The earthquake described happened somewhere east of Jerusalem, most probably along the Jericho fault. Apparently, the offset of the rocks across it was great enough to reveal the northward slip of the eastern side relative to the southward slip of the western side. This motion is remarkably similar to the motion observed in the 1927 Jericho earthquake, and is, of course, consistent with the north-south movement of the plates in this area.
Earlier, around 1020 BC, an earthquake hit Judea during the battle waged by King Saul and his son Jonathan against the Philistines at Michmas. But the biblical accounts of two even older, and simultaneous, events strongly suggest ancient quakes: the crossing of the Jordan by the Israelites and the collapse of the walls of Jericho at the time of Joshua’s siege around 1000 BC. There is little doubt that the walls of this city have collapsed in earthquakes several times in its 10 000-year history. It is likely that an earthquake caused their collapse during the siege by Joshua’s army, especially because the flow in the Jordan River was cut off at that time.
This is recorded in the Book of Joshua: ‘And as they that bare the ark were come unto Jordan, and the feet of the priests that bare the ark were dipped in the brim of the water, (for Jordan overfloweth all his banks all the time of harvest), that the waters which came down from above stood and rose up upon a heap very far from the city Adam, that is beside Zaretan: and those that came down toward the sea of the plain, even the salt sea, failed, and were cut off: and the people passed right against Jericho.’ (Joshua, ch 3 v 15-16)
Adam is now Damiya, the site of the mud slides that in 1927 cut off the flow of the Jordan. Such disruptions, typically lasting one or two days, have also been recorded in 1906, 1834, 1546, 1534, 1267 and 1160. The combination of the destruction of Jericho and the stoppage of the Jordan is so typical of earthquakes in this region that there is little doubt about the reality of earthquakes in Joshua’s time.
One other well-known passage from the Bible may also refer to an earthquake: the description of the destruction of Sodom and Gomorrah, in approximately 2000 BC. ‘Then the Lord . . . overthrew those cities, and all the plain, and all the inhabitants of the cities, and that which grew upon the ground.’ (Genesis, ch 20 v 24-25)
Although the exact location of these extinct cities is not known, it is quite likely that they lay in the plain north of the Dead Sea, and east of Jericho, very close to the line of the Jericho fault. Just as earthquakes in southern California produce great clouds of dust that rise from the dry ground, so an earthquake in Sodom and Gomorrah could have appeared to Abraham as great clouds of ‘smoke’: ‘And Abraham . . . looked toward Sodom and Gomorrah, and toward all the land of the plain, and beheld, and, lo, the smoke of the country went up as the smoke of a furnace.’ (Genesis, ch 19 v 27-28)
At approximately 4000 years old this is the oldest record of an earthquake in history and the start of a sequence of events with which we can reconstruct, in part, the pattern of damaging earthquakes on the Jericho fault. The greatest buildings in Judea, among them the church of the Holy Sepulchre and Al Aqsa mosque in Jerusalem, have been damaged repeatedly, and many people have died. Although the methods of recording them have altered, the events continue.
Predicting where and when such damage is likely in the future remains a major challenge for earth scientists today. The records of the past 40 centuries have proved valuable in ways their authors could never have imagined.
Amos Nur was born and raised in Israel and is now chairman of the Department of Geophysics at Stanford University, California. The film The walls came tumbling down; Earthquakes in the Holy Land is available from ESI Productions, PO Box 2365, Stanford, California 94309.