HISTORY OF EARTHQUAKES AND TSUNAMIS IN ...

WCCE – ECCE – TCCE Joint Conference: EARTHQUAKE & TSUNAMI

HISTORY OF EARTHQUAKES AND TSUNAMIS IN THE ARABIAN GULF: POTENTIAL HAZARD FOR RECLAIMED ISLAND COMMUNITIES A. Kumar1 ABSTRACT Arabian Gulf states are developing several reclaimed islands and building offshore townships. Long term (100 ± 25 years) sustainability of these projects is questioned and assessed in view of possible geological hazards that have struck this region in the past and might strike any time in the future. Such hazards include seismic, tsunami and/or tidal waves, and constant erosion of the reclaimed islands due to surface and sub-marine currents. All these construction projects are challenging and require tremendous caution against the unpredictable yet extremely dangerous natural events over which human ingenuity has absolutely no control. It is recommended that new townships having beach side homes should be developed along the onshore coastal regions. This would be relatively safer against earthquakes and tsunamis than the offshore reclaimed island communities. Keywords: Reclaimed Islands, Earthquakes, Tsunamis, Arabian Gulf INTRODUCTION The December 26, 2004 Sumatra earthquake followed by disastrous tsunamis killed over 250,000 people in a short span of time in Indonesia, Thailand, Sri Lanka and India and caused enormous damage to land and property. This horrific act of nature has engraved a deep scar in our memory. This event has jolted scientists, engineers, planners and authorities to think seriously about the issues like building code that meets seismicity of the region, protection from coastal flooding and planning construction of new townships that are relatively safer from such unforeseen natural disasters (Harinarayana and Hirata, 2005; Murty et al. 2007). Bou-Rabee and VanMarcke (2001) suggested that risk and vulnerability assessment against earthquakes and tsunamis are needed for all the countries of the Arabian Gulf region. Several new townships are under construction on the reclaimed islands along the coastal regions of the Arabian Gulf countries (Figure 1). The city Dubai in United Arab Emirates (UAE) is developing five giant new offshore island communities (websites 1 and 2). They are ‘The Palm Jebel Ali’, ‘The Palm Jumeirah’, ‘The Palm Deira’, ‘The World’ and ‘The Universe’. Qatar (website 3) and Bahrain (website 4) are also developing similar projects on reclaimed land. These islands have been designed for maximum possible length of coastlines so that a large number of beachside luxury homes could be built. Such projects include tens of thousands of homes, apartments, hotels, marinas, golf courses, and other types of commercial and recreational complexes etc. Such projects in Qatar and Bahrain include high rise apartment complexes also. There is a general sense among people of this region that the Arabian Gulf countries are safe from natural disasters like earthquakes and tsunamis. Bou-Rabee and VanMarcke (2001) discussed threats from earthquakes and tsunamis in the countries of the Arabian Gulf region and emphasized that there is an urgent need for risk assessment of infrastructure systems, coastal developments and tall buildings in this region. They also consider that building codes in the region currently lack seismic provisions despite enormous scientific evidence for such a threat. This paper investigates long-term (100 ± 25 years) sustainability of these reclaimed island projects in view of possible geological hazards that have struck this region in the past and might strike anytime in the future. These include seismic, tsunami and/or tidal waves, and erosion due to surface and sub-marine currents.

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Center for Petroleum and Minerals, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia

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Figure 1. Bathymetry of the Arabian Gulf showing areas of offshore urban development. Stars show location of reclaimed islands and townships under construction (modified after Purser and Seibold, 1973). EARTHQUAKES Major urban centers in the Arabian Gulf coastal regions like Dubai and other cities are prone to dangers of seismic activity despite the fact that Arabian Peninsula is considered to be a relatively stable region (Figure 2). According to Al-Amri (2005, 2007) there are 25 seismogenic source zones in the Arabian Peninsula and adjacent countries. They are rift systems, strike slip and normal faults, joints, lineaments, subduction and collision zones (Figure 2). The Zagros Thrust Fault demarcates the plate boundary between the Arabian and the Eurasian tectonic plates and is a seismically active zone (Fournier et al. 2006). Large (M ≥ 5) earthquakes occur frequently along this thrust (Figure 3). Even low frequency ground motion amplification could be significant because it can excite vibrations in tall buildings (Rodgers, 2005). On September 11, 2008 a 6.2 M earthquake jolted the Iranian port city of Bandar Abbas. Its epicenter was in the Arabian Gulf 43 km west of Qeshm Island and a tsunami warning was issued. This earthquake shook buildings all over the UAE and high rise towers were specially affected. Earthquakes originating from Iranian Coastal Source Zone (100 to 400 km away) could cause catastrophic damage to high rise buildings of UAE. Seismic hazard of tall non earthquake resistant buildings pose high level of risk from distant earthquakes (Petrovski, 2005). Ambraseys et al. (1982, 1994) provide an excellent historical record of earthquakes in Iran, Egypt, Arabian region and the Red Sea. Several earthquakes originating in Iran have generated tsunamis that have severely impacted the whole Arabian Gulf region (Table 2). The danger of earthquakes would be significantly higher for the reclaimed islands and their tall buildings because reclaimed land is potentially more susceptible to liquefaction and slope failure. Reclamation material in the Arabian Gulf is mainly dredged carbonate sand and little is known about underlying or nearby fracture zones and seismicity (William, 2005). All these factors make tall buildings constructed on reclaimed islands quite dangerous and prone to seismic destruction.

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Figure 2. Tectonic features of the Arabian Peninsula and the adjoining regions (modified after Seber et al. 2000). TSUNAMIS AND TIDAL WAVES: Since the Arabian Gulf is an inland sea with an opening to the Arabian Sea through the narrow Strait of Hormuz, it is to an extent protected from tidal waves, storm surges and tsunamis generated in the Arabian Sea or the Indian Ocean. Thus the Arabian Gulf and surrounding regions are often saved from tsunamis and tidal waves that originate in the Indian Ocean and the Arabian Sea. However some tsunami energy would always leak into the Arabian Gulf region (Murty et al. 2007). Bhaskaran et al. (2007) calculated tsunami travel time for 250 locations in 35 countries around the Indian Ocean for the December 26, 2004 Sumatra Earthquake. The authors included Manama (Bahrain), Bandar Abbas, Bander-e-Bushehr and Jask (Iran), Kuwait City (Kuwait), Doha and Dukhan (Qatar), Abu Dhabi, Dubai, and Sharjah (UAE) from the Arabian Gulf region. The Kachchh region of Gujarat in western India and the Makran coast of southern Iran and Pakistan have experienced tsunamigenic earthquakes in the past.

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Figure 3. The boundary and seismicity of the Arabian Plate (after Pararas-Carayan, 2006). Rastogi (2007) and Rastogi and Jaiswal (2006) compiled a comprehensive list of tsunamis of the Indian Ocean region and listed tsunamigenic earthquakes in the Arabian Sea that potentially had impacted the coastal regions of the Arabian Gulf (Table 1). Table 1. List of tsunamis generated by earthquakes of Indian Subcontinent that potentially had impacted the Arabian Gulf region.

DATE

LOCATION

CAUSE

326 BC

Kachchh region/ Indus Delta

Earthquake

April 1- May 9, 1008

Iranian coast in Arabian Gulf

Earthquake

1524 AD

Off Dabhol coast, Maharashtra, India

Earthquake

June 16, 1819

Kachchh region, Gujarat, W. India

Earthquake

June 19, 1845

Kachchh region, Gujarat, W. India

Earthquake

Nov. 28, 1945

Makran Coast, Southern Pakistan

Earthquake

Similarly Bou-Rabee and VanMarcke (2001), Jordan et al. (2006) and Jordan (2008) compiled lists of earthquakes and possibly related tsunami events in the Arabian Gulf (Table 2). Bou-Rabee and VanMarcke (2001) specially mention the September, 1871 ‘Al-Tabah’ tsunami event in which most Kuwaiti trading ships (and most likely ships belonging to other countries also) were sunk in the Arabian Gulf and the Arabian Sea causing massive coastal flooding all along the Arabian Gulf leading to high human mortality. Most probably ‘Al-Tabah’ tsunami event was caused by an earthquake at Bushehr, Iran on the same date.

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Table 2. List of tsunamis generated by earthquakes with in the Arabian Gulf region. DATE

LOCATION

TSUNAMI

COMMENTS

June 17, 978

Siraf, Iran

Tsunami, coastal flooding

over 2000 people killed, sank ships

Spring, 1008

Siraf, Iran

? tsunami or a storm surge

Large waves sank ships, people killed

Nov., 1426

Near Bahrain

None recorded

Earthquake

Sept. 1871

? earthquake at Bushehr, Iran

Tsunami, coastal flooding

Al-Tabah event, ships sunk, people killed

~ 1832

Hufuf, Saudi Arabia

None recorded

Earthquake

June 13, 1858

Bushehr, Iran

None recorded

Earthquake

May 19, 1884

Qeshm Island, Iran

None recorded

Felt at Ra’s al-Khaima

Nov. 27, 2005

Qeshm Island, Iran

None recorded

Felt in Dubai, Sharjah

The Makran earthquake of November 28, 1945 and resulting tsunami was deadliest for the South Asian region that generated wave heights up to 11.5 m (Dimri and Srivastava, 2007) and run-ups up to 17 m on the Makran coast (Murty et al. 1999; Pararas-Carayan, 2006). More than 4000 people were killed along the Makran coast of southern Iran and Pakistan and few in Kachchh region of western India and the western Indian city of Mumbai also. This tsunami affected the Iranian coast in the Arabian Gulf region also (Chadha, 2007; Pararas-Carayan, 2006). Makran tsunami waves also swept into the Arabian Gulf and washed out a large sandbar at Ras al-Khaimah, UAE (Jordan, 2008). I am not aware of any written records of Makran coast tsunami in the Arabian Gulf. But as per the local anecdote several fishermen died due to a series of wave upsurges on the Arabian Gulf coastal regions of Saudi Arabia. According to Pararas-Carayan (2006), “seismotectonics of the Makran subduction zone, historical earthquakes in the region, the recent earthquake of October 8, 2005 in Northern Pakistan, and the great tsunamigenic earthquakes of December 26, 2004 and March 28, 2005, are indicative of the active tectonic collision process that is taking place along the entire southern and southeastern boundary of the Eurasian plate as it collides with the Indian plate and adjacent microplates thus “the Makran subduction zone has a relatively high potential for large tsunamigenic earthquakes”. The earthquakes occur quite frequently in Iran and adversely impact the Arabian Gulf region. But most such earthquakes are not tsunamigenic, however their recurrence in future can not be ruled out. Mokhtari et al. (2008) used 2D seismic reflection data to delineate the regional tectonic elements of the Makran region and the Gulf of Oman and concluded that this region is prone to future tsunamis. A review of archival research has shown that average repeat period of magnitude 8+ earthquakes along the Makran Subduction Zone (MSZ) is between 100 to 250 years and this region is capable of producing both tectonic and volcanic tsunami (Heiderzadeh et al. 2008). The numerical modeling of 1945 Makran tsunami indicates that in case of a similar tsunami event Iran and Pakistan will experience wave heights of up to 5-7 m, 5 m in northern coast of Oman and 2 m in the eastern coast of the United Arab Emirates (Heiderzadeh et al. 2009). In case such events occur they will definitely adversely impact reclaimed island communities being developed in the Arabian Gulf. DISCUSSIONS AND CONCLUSIONS The Arabian Gulf region is susceptible to earthquake and tsunami hazards in addition to danger from tidal waves, and coastal erosion. Due to constant subduction pressure of the Arabian Plate under the Eurasian Plate, Iran and the surrounding region including the Arabian Gulf countries are prone to high level seismic activity. In the past this region has been hit by several tsunamigenic earthquakes. Movement of waves and surface currents in the Arabian Gulf poses severe threat of erosion to these reclaimed island communities. Constant stabilization effort will be required to sustain them.

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This paper amply demonstrates the lurking dangers posed by geological hazards to these reclaimed islands and extrovertly fancy communities. Such hazards have struck the region during the past and there is enough scientific evidence to believe that this region is likely to be struck in the future also. It is argued that the long term sustainability of these reclaimed island communities is questionable. Thus it is suggested that since the Arabian Gulf states have plenty of land and long coast line, new townships should be planned and developed on the onshore coastal regions. Onshore developments would be relatively safer than the communities developed on the offshore reclaimed islands. ACKNOWLEDGEMENTS I thank Research Institute, King Fahd University of Petroleum and Minerals, Saudi Arabia for permission to publish this paper. REFERENCES Al-Amri, A. M. (2005). Seismic source zones of the Arabian Peninsula and adjacent countries. Gulf Seismic Forum, United Arab Emirates University, Al-Ain, UAE. , Abstract pp. 2-3. Al-Amri, A. M. (2007). Characterization of seismic zones in the Arabian Peninsula. 7th Meeting of the Saudi Society for Geosciences. King Saud University, Riyadh., Abstract pp. 56. Ambraseys, N. N. and Melville, C. P. (1982). A history of Persian Earthquakes. Cambridge University Press, New York. Ambraseys, N. N., Melville, C. P. and Adams, R. D. (1994). The Seismicity of Egypt, Arabia and the Red Sea. Cambridge University Press, New York. Bhaskaran, P. K., Dube, S. K., Murty, T. S., Gangopadhyay, A., Chaudhury, A., Rao, A. D. (2007). Tsunami travel time atlas for the Indian Ocean. In. Murty, T. S., Aswathanarayana, U. and Nirupama, N. (Eds.). The Indian Ocean Tsunami. Taylor and Francis, London, pp. 273-292. Bou-Rabee, F. and VanMarcke, V. 2001. Seismic vulnerability of Kuwait and other Arabian Gulf countries: information base and research needs. Soil Dynamics and Earthquake Engineering, v. 21, pp. 181-186. Chadha, R. K. (2007). Tsunamigenic sources in the Indian Ocean: factors and impact on the Indian Landmass. In. Murty, T. S., Aswathanarayana, U. and Nirupama, N. (Eds.). The Indian Ocean Tsunami. Taylor and Francis, London, pp. 33-48. Dimri, V. P. and Srivastava, K. (2007). Modelling techniques for understanding the Indian Ocean tsunami propagation. In. Murty, T. S., Aswathanarayana, U. and Nirupama, N. (Eds.). The Indian Ocean Tsunami. Taylor and Francis, London, pp. 123-130. Fournier, M., Lepvrier, C., Razin, P. and Jolivet, L. (2006). Late Cretaceous to Paleogene post-obduction extension and subsequent Neogene compression in the Oman Mountains. GeoArabia, v. 11(4), pp. 1739. Harinarayana, T. and Hirata, N. (2005). Destructive earthquake and disastrous tsunami in the Indian Ocean, what next? Gondwana Research, v. 8(2): 246-257. Heidarzadeh, M., Pirooz, M. D., Zaker, N. H., Yalciner, A. C., Mokhtari, M. and Esmaeily, A. 2008. Historical tsunami in the Makran Subduction Zone off southern coasts of Iran and Pakistan and results of numerical modeling. Ocean Engineering, 35: 774-786. Heidarzadeh, M., Pirooz, M. D., Zaker, N. H., Yalciner, A. C. 2009. Preliminary examination of the tsunami hazards associated with the Makran subduction zone at the northwestern Indian Ocean, Nat. Hazard, 48:229-243. Jordan, B. R. (2008). Tsunamis of the Arabian Peninsula, a guide of historic events. Science of Tsunami Hazards. v. 27 (1), pp. 31- 46. Jordan, B. R., Baker, H. and Howari, F. (2006). Tsunami hazards along the coasts of the United Arab Emirates. Dubai Municipality Publication. Mokhtari, M., Fard, I. A., and Hessami, K. 2008. Structural elements of the Makran region, Oman sea and their potential relevance to tsunamigenesis. Nat. Hazards, 47: 185-199. Murty, T. S., Bapat, A., and Prasad, V. (1999). Tsunamis on the coastlines of India. Sci. Tsunami Hazards, v. 17(3): pp. 167-172.

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Murty, T. S., Aswathanarayana, U. and Nirupama, N. (2007). The Indian Ocean Tsunami. Taylor and Francis, London, pp. 1- 491. Pararas-Carayan, G. (2006).The potential of tsunami generation along the Makran Subduction Zone in the northern Arabian Sea: Case study: The earthquake and tsunami of November 28, 1945. Science of Tsunami Hazard, v. 24(5), 358-384. Petrovski, J. T. (2005). Seismic risk of tall buildings and structures caused by distant earthquakes. Gulf Seismic Forum, United Arab Emirates University, Al-Ain, UAE., Abstract pp. 35-40. Purser, H. B. and Seibold, E. (1973). The principal environmental factors influencing Holocene sedimentation and diagenesis in the Persian Gulf. In: The Persian Gulf. Holocene carbonate sedimentation and diagenesis in shallow epicontinental sea. (Ed.) B. H. Purser. Springer-Verlag, Berlin, pp. 1- 471. Rastogi, B. K. (2007). A historical account of the earthquakes and tsunamis in the Indian Ocean. In. Murty, T. S., Aswathanarayana, U. and Nirupama, N. (Eds.). The Indian Ocean Tsunami. Taylor and Francis, London, pp. 3-18. Rastogi, B. K. and Jaiswal, R. K. (2006). A catalogue of tsunamis in the Indian Ocean. Science of Tsunami Hazard, v. 25 (3): 128-143. Rodgers, A. (2005). Ground motion in the gulf region from large earthquakes in Zagros Mountains. Gulf Seismic Forum, United Arab Emirates University, Al-Ain, UAE., Abstract pp. 41. Seber, D., Steer, D., Sandvol, E. and Sandvol, C., Brindisi, C. and Barazangi, M. (2000). Design and development of information systems for the geosciences: An application to the Middle East. GeoArabia, v. 5(2): 269-295. Williams, C. T. (2005). Development and seismic stability in coastal zone. Gulf Seismic Forum, UAE University, Al-Ain, UAE., Abstract pp. 57. Internet References Website 1: http://en.wikipedia.org/wiki/Palm_Islands Website 2: http://www.nakheel.com Website 3: http://www.thepearlqatar.com/main.aspx Website 4: http://www.durratbahrain.com

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