Migration of local earthquakes in the gulf of aqaba, north red sea

ABSTRACTThe Gulf of Aqabah has been considered one of the most seismically-active regions in the Middle East during the last 15 years; a catalogue of 1,415 earthquakes (duration magnitude Md and gt; 2. 8) during 19851995, compiled by Al-Arifi (1996) and Al-Shaabi (1998), mainly based on data from King Saud University. Seismic Studies Center (SSC), Saudi Arabia, for 28°- 30°N and 30°-36°E, has been used for studying local aftershock migration . Aftershocks migrated northwards about 60 km for the 1993 sequence and about 70 km for the 1995 sequence and also to shallow focal depths (15 km focal depth for 1993 main-shock) . Depths reduced as time elapsed until reaching 2 km for the last strong aftershock (Md=5 . 2) which occurred during the late stage of the sequence . The 1993 main-shock caused a redistribution of stresses to the parallel faults' segment where the largest 1993 aftershock occurred triggering these faults' segment to become an area of stress nucleation and generated the 1995 main-shockRESUMENEl Golfo de Aqabah ha sido considerada una de las regiones con más actividad sísmica del Medio Oriente durante los últimos 15 años . Un catalogo de 1415 terremotos (magnitud de duración Md and gt;2. 8) entre 1985-1995, compilado por Al-Arifi (1996) y Al-Shaabi (1998), basado principalmente en datos de la Universidad King Saud, Centro de Estudios Sísmicos (SSC), Arabia Saudita, para la zona ubicada entre 28°- 30°N y 30°-36°E, ha sido usado para estudiar la migración de replicas locales Las replicas migraron unos 60 km al norte para la secuencia correspondiente al año 1993 y unos 70 km para la secuencia por el año 1995 y también hacia bajas profundidades focales (15km de profundidad focal para el evento principal en el año 1993) . Las profundidades se redujeron con el tiempo hasta alcanzar 2 km para la ultima replica fuerte (Md=5 2) que ocurrió durante la última etapa de la secuencia El principal evento del año 1993 causo una redistribución de los esfuerzos hacia el segmento de las fallas paralelas donde la mayor replica en el año 1993 ocurrió, desencadenando el movimiento de estas fallas para llegar a ser un área de nucleación y generando el principal evento en el año 199

Physico-chemical characteristics of Jharkhand and West Bengal thermal springs along SONATA mega lineament, India

The chemical and isotopic compositions of thermal springs located along the Son–Narmada–Tapti (SONATA) mega lineament in central India have been investigated. The issuing temperatures of the thermal waters vary from 31° to 89°C for the thermal springs and 24° to 25°C for the cold springs. These thermal springs are located on the Archean Chotanagpur Gneissic Complex (CGC) in the eastern part of peninsular India. The thermal springs are mostly alkaline in nature with pH varying from 7.5 to 9.5. Piper diagram suggests that the chemistry of the thermal waters is compatible with the granitic host rocks through which the waters circulate. Mineral saturation index suggests that the thermal waters are saturated with cristobalite and quartz at lower temperatures (less than ∼130 to 150°C), and calcite and forsterite at higher temperatures (∼160° to 250°C). The estimated reservoir temperature based on chemical geothermometers is in the range of 132°–265°C, which favours a medium enthalpy geothermal system. Oxygen isotope fractionation of Bakreswar and Tantloi thermal springs highlights a higher reservoir temperature than estimated by chemical geothermometer. Positive gravity anomalies over Bakreswar and Tantloi areas strongly suggest a basement/mantle upliftment or mafic intrusion which could account for the heat source close to the surface. However, the large negative gravity anomaly depression around the Surajkund and Katkamsandi thermal springs indicates presence of deep seated faults

The potential contribution of geothermal energy to electricity supply in Saudi Arabia

With increase in demand for electricity at 7.5% per year, the major concern of Saudi Arabia is the amount of CO2 being emitted. The country has the potential of generating 200 × 106 kWh from hydrothermal sources and 120 × 106 terawatt hour from Enhanced Geothermal System (EGS) sources. In addition to electricity generation and desalination, the country has substantial source for direct application such as space cooling and heating, a sector that consumes 80% of the electricity generated from fossil fuels. Geothermal energy can offset easily 17 million kWh of electricity that is being used for desalination. At least a part of 181,000 Gg of CO2 emitted by conventional space cooling units can also be mitigated through ground-source heat pump technology immediately. Future development of EGS sources together with the wet geothermal systems will make the country stronger in terms of oil reserves saved and increase in exports

Geothermal energy for sustainable water resources management

With ever-increasing population and steep declining freshwater supply, the future concern of MENA and Sub-Saharan countries is food security. Egypt is more vulnerable to food security due to the increased water rights being exercised by the countries sharing the Nile River. Assuming that Egypt by 2025 will achieve 1000 m3/y per capita consumption of water, with the population growing beyond 109 millions, the water available by 2025 would be around 106 billion m3/y. With increasing pressure from the Nile River basin riparian countries, Egypt may not be able to manage with the current 58 billion m3 of water from the Aswan dam to achieve per capita goal. To maintain the current per capita water consumption of 636 m3/y Egypt may need about 1200 desalination plants and 200 × 106 kWh electricity is required to operate these plants and the CO2 emissions due to this process will be around 80–160 million tones. Electricity generated from hydrothermal sources can supply 659 × 109 m3/year of desalinated water while the EGS can generate 58,400 × 109 m3/y of desalinated water from the Red Sea. This will help the country to meet the current fresh water deficit of 48 × 109 m3/y. By the year 2025, the demand for fresh water will be of the order of 106 × 109 m3/y to maintain 1000 m3/y per capita water consumption. Egypt can set an example to MENA and Sub-Saharan countries by using geothermal energy for sustainable development and future water and food security

Characterization of a fractured basement reservoir using high-resolution 3D seismic and logging datasets: A case study of the Sab'atayn Basin, Yemen.

The Sab'atayn Basin is one of the most prolific Mesozoic hydrocarbon basins located in central Yemen. It has many oil producing fields including the Habban Field with oil occurrences in fractured basement rocks. A comprehensive seismic analysis of fractured basement reservoirs was performed to identify the structural pattern and mechanism of hydrocarbon entrapment and reservoir characteristics. A 3D post-stack time migration seismic cube and logging data of 20 wells were used and several 2D seismic sections were constructed and interpreted. Depth structure maps were generated for the basement reservoir and overlying formations. The top of the basement reservoir is dissected by a set of NW-SE step-like normal faults (Najd Fault System) and to a lesser extent, by secondary NNE-SSW oriented faults (Hadramauwt System). The Najd Fault System is dominant and dissects the reservoir in the middle of the field into two prospective uplifts. The northern and northeastern areas constitute the deep-seated downthrown side of the reservoir. Hydrocarbon emplacement is through the fault juxtaposition of the fractured basement against the organic shale source rock of the overlying Madbi Formation. Hydrocarbons are hosted in basement horsts formed by fault-controlled blocks and overlain by the regional seal of the Sab'atayn Formation. The basement reservoir rock is mainly composed of granite, quartz-feldspar, weathered silica, and mica minerals. Fractures were identified from the outcrops, cores, image logs, and the petrophysical analysis. Hydrocarbon saturation was observed in the upper and middle parts of the reservoir, more specifically in front of the highly fractured sections. The fracture porosity was less than 5% and the dead oil had an API gravity of 40° with no H2S or CO2. In conclusion, the structural highs of the Habban Field are of interest because most oil producing wells are drilled into them. We recommend extending the drilling and development activities in these uplifts

Migration of local earthquakes in the Gulf of Aqaba, North Red Sea

<p style="font-family: verdana; font-size: small;"><strong>ABSTRACT</strong></p><p style="font-family: verdana; font-size: small;">The Gulf of Aqabah has been considered one of the most seismically-active regions in the Middle East during the last 15 years; a catalogue of 1,415 earthquakes (duration magnitude Md > 2. 8) during 19851995, compiled by Al-Arifi (1996) and Al-Shaabi (1998), mainly based on data from King Saud University. Seismic Studies Center (SSC), Saudi Arabia, for 28°- 30°N and 30°-36°E, has been used for studying local aftershock migration . Aftershocks migrated northwards about 60 km for the 1993 sequence and about 70 km for the 1995 sequence and also to shallow focal depths (15 km focal depth for 1993 main-shock) . Depths reduced as time elapsed until reaching 2 km for the last strong aftershock (Md=5 . 2) which occurred during the late stage of the sequence . The 1993 main-shock caused a redistribution of stresses to the parallel faults' segment where the largest 1993 aftershock occurred triggering these faults' segment to become an area of stress nucleation and generated the 1995 main-shock</p><p style="font-family: verdana; font-size: small;"><p><strong>RESUMEN</strong></p><p>El Golfo de Aqabah ha sido considerada una de las regiones con más actividad sísmica del Medio Oriente durante los últimos 15 años . Un catalogo de 1415 terremotos (magnitud de duración Md>2. 8) entre 1985-1995, compilado por Al-Arifi (1996) y Al-Shaabi (1998), basado principalmente en datos de la Universidad King Saud, Centro de Estudios Sísmicos (SSC), Arabia Saudita, para la zona ubicada entre 28°- 30°N y 30°-36°E, ha sido usado para estudiar la migración de replicas locales Las replicas migraron unos 60 km al norte para la secuencia correspondiente al año 1993 y unos 70 km para la secuencia por el año 1995 y también hacia bajas profundidades focales (15km de profundidad focal para el evento principal en el año 1993) . Las profundidades se redujeron con el tiempo hasta alcanzar 2 km para la ultima replica fuerte (Md=5 2) que ocurrió durante la última etapa de la secuencia El principal evento del año 1993 causo una redistribución de los esfuerzos hacia el segmento de las fallas paralelas donde la mayor replica en el año 1993 ocurrió, desencadenando el movimiento de estas fallas para llegar a ser un área de nucleación y generando el principal evento en el año 1995</p></p&gt