Jordan Rift Valley

The Jordan Rift Valley, also Jordan Valley (Hebrew: בִּקְעָת הַיַרְדֵּן Bīqʿāt haYardēn, Arabic: الغور Al-Ghor or Al-Ghawr),^{[citation needed]} also called the Syro-African Depression,^{[dubious – discuss]} is an elongated depression located in modern-day Israel, Jordan and the West Bank. This geographic region includes the entire length of the Jordan River – from its sources, through the Hula Valley, the Korazim block, the Sea of Galilee, the (Lower) Jordan Valley, all the way to the Dead Sea, the lowest land elevation on Earth – and then continues through the Arabah depression, the Gulf of Aqaba whose shorelines it incorporates, until finally reaching the Red Sea proper at the Straits of Tiran.

History and physical features

Northern section of the Great Rift Valley. The Sinai Peninsula is in center and the Dead Sea and Jordan River valley above.

The Jordan Rift Valley was formed many millions of years ago in the Miocene epoch (23.8 – 5.3 Myr ago) when the Arabian plate moved northward and then eastward away from Africa. One million years later, the land between the Mediterranean and the Jordan Rift Valley rose so that the sea water stopped flooding the area. Alternatively, it was a fall in the sea level that caused the disconnection, or a mix between the two phenomena – researchers have not yet reached a consensus.

The geological and environmental evolution of the valley since its inception in the Oligocene can be seen in a variety of sedimentary and magmatic rock units, preserved as continuous sequences in the deeper basins. The outcropping formations around the basins represent alternating deposition and erosion phases.^[1]

The lowest point in the Jordan Rift Valley is in the Dead Sea, the lowest spot of which is 790 m (2,590 ft) below sea level.^{[dubious – discuss]} The shore of the Dead Sea is the lowest dry land spot on Earth, at 400 m (1,300 ft) below sea level. With its flanks rising sharply to almost 1,000 m (3,300 ft) above sea level in the west, and similarly in the east, the rift is a significant topographic feature over which a few narrow paved roads and difficult mountain tracks lead.^[2] The valley north of the Dead Sea has long been a site of agriculture because of water available from the Jordan River and numerous springs located on the valley's flanks.

Dead Sea Transform

The plate boundary that extends through the valley is variously called the Dead Sea Transform (DST) or Dead Sea Rift. The boundary separates the Arabian plate from the African plate, connecting the divergent plate boundary in the Red Sea (the Red Sea Rift) to the East Anatolian Fault in Turkey.^[3]

The DST fault system is generally considered to be a transform fault that has accommodated a 105-kilometre (65 mi) northwards displacement of the Arabian plate.^[4]^[5] This interpretation is based on observation of offset markers, such as river terraces, gullies and archaeological features, giving horizontal slip rates of several mm per year over the last few million years.^[6] GPS data give similar rates of present-day movement of the Arabian plate relative to the Africa plate.^[7] It has also been proposed that the fault zone is a rift system that is an incipient oceanic spreading center, the northern extension of the Red Sea Rift.^[8]

In 1033, the rift valley was struck by a magnitude 7.3 earthquake, believed to have been produced along the DST fault system.^[9] It caused widespread destruction, a tsunami, and killed 70,000 people.^[10]

Seismic risk

The 1033 AD event was the last large earthquake on the Jordan Valley Fault. Given the estimated slip rate is 4.9 ± 0.2 mm (0.1929 ± 0.0079 in) per year, approximately 5 m (16 ft) of potential slip has been accumulated. An estimated 3.5–5 m (11–16 ft) of slip could be produced during a future earthquake along a 110 km (68 mi) × 20 km (12 mi) fault area. Such an event would suggest an earthquake of M_w  7.4, posing a great seismic threat to the region.^[11]

In late 2020, researchers at Tel Aviv University said that an earthquake of magnitude 6.5 is expected to occur in the area, resulting in many fatalities. Researchers also stated that the frequency of large earthquakes in the region is significantly underestimated.^[12] Previous studies suggested a recurrence interval of 10,000 years for magnitude 7.5 earthquakes, but the researchers said the figure was 1,300 to 1,400 years.^[13] Yosef Shapira, the then State Comptroller of Israel, said that a major earthquake in Israel could kill up to 7,000 people if safety recommendations are not enforced. Reports of the years 2001, 2004 and 2011 found that the Israeli government did not fund any retrofitting works to old construction. Although the government said in 2008 that it would retrofit hospitals and schools, no major changes were made.^[14]

Climate

Climate data for Dead Sea, Sedom (-390m)
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Record high °C (°F)	26.4 (79.5)	30.4 (86.7)	33.8 (92.8)	42.5 (108.5)	45.0 (113.0)	46.4 (115.5)	47.0 (116.6)	44.5 (112.1)	43.6 (110.5)	40.0 (104.0)	35.0 (95.0)	28.5 (83.3)	47.0 (116.6)
Mean daily maximum °C (°F)	20.5 (68.9)	21.7 (71.1)	24.8 (76.6)	29.9 (85.8)	34.1 (93.4)	37.6 (99.7)	39.7 (103.5)	39.0 (102.2)	36.5 (97.7)	32.4 (90.3)	26.9 (80.4)	21.7 (71.1)	30.4 (86.7)
Daily mean °C (°F)	16.6 (61.9)	17.7 (63.9)	20.8 (69.4)	25.4 (77.7)	29.4 (84.9)	32.6 (90.7)	34.7 (94.5)	34.5 (94.1)	32.4 (90.3)	28.6 (83.5)	23.1 (73.6)	17.9 (64.2)	26.1 (79.0)
Mean daily minimum °C (°F)	12.7 (54.9)	13.7 (56.7)	16.7 (62.1)	20.9 (69.6)	24.7 (76.5)	27.6 (81.7)	29.6 (85.3)	29.9 (85.8)	28.3 (82.9)	24.7 (76.5)	19.3 (66.7)	14.1 (57.4)	21.9 (71.4)
Record low °C (°F)	5.4 (41.7)	6.0 (42.8)	8.0 (46.4)	11.5 (52.7)	19.0 (66.2)	23.0 (73.4)	26.0 (78.8)	26.8 (80.2)	24.2 (75.6)	17.0 (62.6)	9.8 (49.6)	6.0 (42.8)	5.4 (41.7)
Average precipitation mm (inches)	7.8 (0.31)	9.0 (0.35)	7.6 (0.30)	4.3 (0.17)	0.2 (0.01)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	1.2 (0.05)	3.5 (0.14)	8.3 (0.33)	41.9 (1.65)
Average precipitation days	3.3	3.5	2.5	1.3	0.2	0.0	0.0	0.0	0.0	0.4	1.6	2.8	15.6
Average relative humidity (%)	41	38	33	27	24	23	24	27	31	33	36	41	32
Source: Israel Meteorological Service^[15]

Climate data for Gilgal (−255m)
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Record high °C (°F)	28.0 (82.4)	33.5 (92.3)	40.5 (104.9)	44.7 (112.5)	46.5 (115.7)	47.5 (117.5)	48.1 (118.6)	49.0 (120.2)	45.7 (114.3)	44.2 (111.6)	37.9 (100.2)	32.5 (90.5)	49.0 (120.2)
Mean daily maximum °C (°F)	20.1 (68.2)	21.6 (70.9)	25.6 (78.1)	30.3 (86.5)	35.6 (96.1)	38.7 (101.7)	40.4 (104.7)	40.0 (104.0)	37.7 (99.9)	33.8 (92.8)	27.7 (81.9)	22.1 (71.8)	31.1 (88.1)
Daily mean °C (°F)	14.5 (58.1)	15.5 (59.9)	18.7 (65.7)	22.8 (73.0)	27.3 (81.1)	30.5 (86.9)	32.4 (90.3)	32.5 (90.5)	30.5 (86.9)	26.9 (80.4)	21.1 (70.0)	16.4 (61.5)	24.1 (75.4)
Mean daily minimum °C (°F)	8.9 (48.0)	9.4 (48.9)	11.8 (53.2)	15.3 (59.5)	19.1 (66.4)	22.3 (72.1)	24.5 (76.1)	25.0 (77.0)	23.2 (73.8)	19.9 (67.8)	14.4 (57.9)	10.6 (51.1)	17.0 (62.7)
Record low °C (°F)	0.3 (32.5)	0.0 (32.0)	2.5 (36.5)	3.0 (37.4)	11.2 (52.2)	15.2 (59.4)	20.0 (68.0)	19.5 (67.1)	14.0 (57.2)	12.1 (53.8)	4.6 (40.3)	0.2 (32.4)	0.0 (32.0)
Source: Israel Meteorological Service^[16]

References

^ The Jordan Rift Valley Archived 24 September 2015 at the Wayback Machine, Tel Aviv University
^ David Eshel (3 May 2006). "Increasing Importance of the Jordan Rift Buffer". Defense Update. Archived from the original on 5 July 2008. Retrieved 5 July 2007.
^ "The Geophysical Institute". Archived from the original on 23 June 2008.
^ Freund R.; Garfunkel Z.; Zak I.; Goldberg M.; Weissbrod T.; Derin B.; Bender F.; Wellings F.E.; Girdler R.W. (1970). "The Shear along the Dead Sea Rift (and Discussion)". Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences. 267 (1181): 107. Bibcode:1970RSPTA.267..107F. doi:10.1098/rsta.1970.0027.
^ Joffe S.; Garfunkel Z. (1987). "Plate kinematics of the circum Red Sea—a re-evaluation". Tectonophysics. 141 (1–3): 5–22. Bibcode:1987Tectp.141....5J. doi:10.1016/0040-1951(87)90171-5.
^ Begin Z.B.; Steinitz G. (2005). "Temporal and spatial variations of microearthquake activity along the Dead Sea Fault, 1984–2004". Israel Journal of Earth Sciences. 54: 1–14. doi:10.1560/QTVW-HY1E-7XNU-JCLJ (inactive 1 November 2024).{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link)
^ Gomez, F., Karam, G., Khawlie, M., McClusky S., Vernant P., Reilinger R., Jaafar R., Tabet C., Khair K., and Barazangi M (2007). "Global Positioning System measurements of strain accumulation and slip transfer through the restraining bend along the Dead Sea fault system in Lebanon". Geophysical Journal International. 168 (3): 1021–1028. Bibcode:2007GeoJI.168.1021G. doi:10.1111/j.1365-246X.2006.03328.x. hdl:1885/36424.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ Mart Y.; Ryan W.B.F.; Lunina O.V. (2005). "Review of the tectonics of the Levant Rift system: the structural significance of oblique continental breakup". Tectonophysics. 395 (3–4): 209–232. Bibcode:2005Tectp.395..209M. doi:10.1016/j.tecto.2004.09.007.
^ Grigoratos, Iason; Poggi, Valerio; Danciu, Laurentiu; Rojo, Graciela (14 February 2020). "An updated parametric catalog of historical earthquakes around the Dead Sea Transform Fault Zone". Journal of Seismology. 24 (4): 803–832. Bibcode:2020JSeis..24..803G. doi:10.1007/s10950-020-09904-9. S2CID 211102430.
^ National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information (1972). "Significant Earthquake Information". NOAA National Centers for Environmental Information. doi:10.7289/V5TD9V7K. Retrieved 22 June 2022.
^ Ferry, Matthieu; Meghraoui, Mustapha; Karaki, Najib Abou; Al-Taj, Masdouq; Amoush, Hani; Al-Dhaisat, Salman; Barjous, Majdi (30 August 2007). "A 48-kyr-long slip rate history for the Jordan Valley segment of the Dead Sea Fault". Earth and Planetary Science Letters. 260 (3–4): 394–406. Bibcode:2007E&PSL.260..394F. doi:10.1016/j.epsl.2007.05.049.
^ Winer, Stuart (29 December 2020). "Major earthquake, killing hundreds, likely to hit Israel in coming years – study". The Times of Israel. Retrieved 22 June 2022.
^ Lu, Yin; Wetzler, Nadav; Waldmann, Nicolas; Agnon, Amotz; Biasi, Glenn P.; Marco, Shmuel (2020). "A 220,000-year-long continuous large earthquake record on a slow-slipping plate boundary". Science Advances. 6 (48). Bibcode:2020SciA....6.4170L. doi:10.1126/sciadv.aba4170. PMC 7695470. PMID 33246948.
^ "State comptroller: Israel unprepared for major quake, ignoring warnings". The Times of Israel. 18 July 2018. Retrieved 22 June 2022.
^ "Averages and Records for several places in Israel". Israel Meteorological Service. June 2011. Archived from the original on 14 September 2010.
^ "Averages and Records for several places in Israel" (PDF). Israel Meteorological Service. January 2016. Archived from the original (PDF) on 30 January 2016.