Zvi Ben-Avraham | Tel Aviv University (original) (raw)
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Papers by Zvi Ben-Avraham
Fifth International Conferention on Ground Penetrating Radar, 1994
Tectonophysics, 2020
Abstract The cities of Elat, Israel and neighboring Aqaba, Jordan are major economic, cultural, a... more Abstract The cities of Elat, Israel and neighboring Aqaba, Jordan are major economic, cultural, and seaport centers. They are located on the northern shore of the Gulf of Aqaba/Elat (GAE) directly on the Dead Sea Transform. Yet the precise location of the fault trace and its tectonic activity are lacking. The interpretation of seismic reflection profiles across the GAE beach and paleoseismic trench data located 2.2 km north of the shoreline provide evidence that the active offshore mapped Avrona Fault extends onland along the eastern side of the Elat Sabkha (mudflat), where three prominent fault strands crosscut the sedimentary fill. Mismatch of reflector geometry across the faults and flower structures indicate strike-slip faulting with a normal-slip component. Subsurface data from two trenching sites provide evidence for a minimum of two surface ruptures and two paleoliquefaction events. Faulting is constrained by radiocarbon dating for an Event 1 between 897 and 992 CE and Event 2 after 1294 CE. We suggest that the historically documented 1068 CE, and at least one later earthquake in 1458 or 1588 CE, ruptured the Elat Sabkha site. Based on fault mapping, we suggest a minimum value of M 6.6 for the 1068 CE earthquake. Whereas no surface rupture was observed for the 1212 CE historical earthquake, fluidized strata radiocarbon dated to before 1269–1389 CE identified as paleoliquefaction may be attributed to it. Two liquefaction sand-blows mapped in the trench likely formed after 1337 CE and before 1550 CE, which possibly occurred at the same time as in the second faulting event. Our data suggest that no large event occurred along the Avrona segment in the past ~430–550 years. Given a ~ 5 mm/yr slip rate, we conclude that a significant period of time passed since the last surface rupturing on the Avrona Fault, increasing its seismic potential.
AGU Fall Meeting Abstracts, Dec 1, 2013
AGU Fall Meeting Abstracts, Dec 1, 2012
Quaternary Science Reviews, Apr 1, 2019
EGU General Assembly Conference Abstracts, Apr 1, 2017
Basin Research, Jul 30, 2019
Tectonophysics, Dec 1, 1994
Geo-Marine Letters
The Eastern Mediterranean continental slope offshore Israel became a focus of exploration for, an... more The Eastern Mediterranean continental slope offshore Israel became a focus of exploration for, and production of, natural gas in recent years. The 2010–2011 Nautilus ROV expedition performed detailed video recordings and sampling in two areas offshore Israel: the Palmachim disturbance, southwest of Tel Aviv, and an area offshore Acre, north of Haifa. An analytical programme regarding the carbonate structures was carried out, examining the overall mineralogy, stable C and O isotopes, and Ca, Mg, and Mn concentrations. This provided information on their composition and as a result, an indication of the carbon sources and temperature of formation. The major authigenic minerals identified comprised magnesian calcite, dolomite, aragonite, and kutnohorite. The detrital minerals included quartz, clays, feldspars, and rare augite and enstatite, likely transported from the Nile estuary. The carbon isotope composition of aliquots taken from nineteen samples from these areas have an overall δ1...
EGU General Assembly Conference Abstracts, Apr 1, 2017
AGU Fall Meeting Abstracts, Dec 1, 2015
The Kinneret-Bet She’an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She’an... more The Kinneret-Bet She’an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She’an sub-basins. The complex developed at the intersection between two major tectonic boundaries: the Oligo-Miocene AzraqSirhan failed rift, that later developed into the southern Galilee basins and Carmel-Gilboa fault system; and the Dead Sea fault (DSF) plate boundary that developed since the Miocene. Despite numerous studies, KBS still remains one of the enigmatic basin complexes. Its structure, stratigraphy and development are vaguely understood – both inside the basin and in correlation with its surroundings. Our study presents a new and comprehensive 3D model for the structure of KBS complex. It is based on all available gravity measurements, adopted from the national gravity database, and new gravity measurements, collected in cooperation with the Geological Survey of Israel and funded by the Ministry of National Infrastructure, Energy and Water Resources. The gravity data were integr...
Coastal marine systems are experiencing rapid transformations as a result of multiple human-induc... more Coastal marine systems are experiencing rapid transformations as a result of multiple human-induced stressors. Many of these transformations occur at the level of a landscape and as such it is increasingly important to detect changes at these appropriate spatial scales. Remote sensing can be a powerful tool to investigate landscape level changes, but it still requires calibration and ground-truth via field observations. In this research, classification schemes using multispectral and hyperspectral imagery were developed in order to map and monitor temporal changes in the benthos over a fifteen-year period (1999-2014) along the Levant Mediterranean rocky reefs that are made of sandstone (known as Kurkar) and are found along the northern coast of Israel. The Levant Mediterranean rocky reef has been experiencing major temporal shifts in marine biodiversity. These shifts include, but are not limited to, the creation of reefs by large oysters that invaded from the Red Sea, the addition of non-native seaweed species, and over-grazing of seaweed beds by non-native herbivorous fish. Such changes can likely be observed at the landscape level. The bathymetry of the reef is characterized by sandstone ridges that are parallel to the shoreline with emerging islands at their top and a long-shallow channel between the ridge and the shore. Using bathymetric models, a correction for the water attenuation was applied to the spectral dataset and an optical extinction depth was calculated. A recent field campaign (May, 2014) in the study area using acoustic (side scan sonar) and underwater optical measurements provided a ground truth dataset for the study. Decision trees used for the classification were developed based on in situ spectral measurements and underwater video imagery. A time series of seafloor characterization maps was derived from imagery acquired using Itres CASI, Landsat 7 and Landsat 8
Quaternary Science Reviews, 2019
Journal of Applied Geophysics, 2018
Fifth International Conferention on Ground Penetrating Radar, 1994
Tectonophysics, 2020
Abstract The cities of Elat, Israel and neighboring Aqaba, Jordan are major economic, cultural, a... more Abstract The cities of Elat, Israel and neighboring Aqaba, Jordan are major economic, cultural, and seaport centers. They are located on the northern shore of the Gulf of Aqaba/Elat (GAE) directly on the Dead Sea Transform. Yet the precise location of the fault trace and its tectonic activity are lacking. The interpretation of seismic reflection profiles across the GAE beach and paleoseismic trench data located 2.2 km north of the shoreline provide evidence that the active offshore mapped Avrona Fault extends onland along the eastern side of the Elat Sabkha (mudflat), where three prominent fault strands crosscut the sedimentary fill. Mismatch of reflector geometry across the faults and flower structures indicate strike-slip faulting with a normal-slip component. Subsurface data from two trenching sites provide evidence for a minimum of two surface ruptures and two paleoliquefaction events. Faulting is constrained by radiocarbon dating for an Event 1 between 897 and 992 CE and Event 2 after 1294 CE. We suggest that the historically documented 1068 CE, and at least one later earthquake in 1458 or 1588 CE, ruptured the Elat Sabkha site. Based on fault mapping, we suggest a minimum value of M 6.6 for the 1068 CE earthquake. Whereas no surface rupture was observed for the 1212 CE historical earthquake, fluidized strata radiocarbon dated to before 1269–1389 CE identified as paleoliquefaction may be attributed to it. Two liquefaction sand-blows mapped in the trench likely formed after 1337 CE and before 1550 CE, which possibly occurred at the same time as in the second faulting event. Our data suggest that no large event occurred along the Avrona segment in the past ~430–550 years. Given a ~ 5 mm/yr slip rate, we conclude that a significant period of time passed since the last surface rupturing on the Avrona Fault, increasing its seismic potential.
AGU Fall Meeting Abstracts, Dec 1, 2013
AGU Fall Meeting Abstracts, Dec 1, 2012
Quaternary Science Reviews, Apr 1, 2019
EGU General Assembly Conference Abstracts, Apr 1, 2017
Basin Research, Jul 30, 2019
Tectonophysics, Dec 1, 1994
Geo-Marine Letters
The Eastern Mediterranean continental slope offshore Israel became a focus of exploration for, an... more The Eastern Mediterranean continental slope offshore Israel became a focus of exploration for, and production of, natural gas in recent years. The 2010–2011 Nautilus ROV expedition performed detailed video recordings and sampling in two areas offshore Israel: the Palmachim disturbance, southwest of Tel Aviv, and an area offshore Acre, north of Haifa. An analytical programme regarding the carbonate structures was carried out, examining the overall mineralogy, stable C and O isotopes, and Ca, Mg, and Mn concentrations. This provided information on their composition and as a result, an indication of the carbon sources and temperature of formation. The major authigenic minerals identified comprised magnesian calcite, dolomite, aragonite, and kutnohorite. The detrital minerals included quartz, clays, feldspars, and rare augite and enstatite, likely transported from the Nile estuary. The carbon isotope composition of aliquots taken from nineteen samples from these areas have an overall δ1...
EGU General Assembly Conference Abstracts, Apr 1, 2017
AGU Fall Meeting Abstracts, Dec 1, 2015
The Kinneret-Bet She’an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She’an... more The Kinneret-Bet She’an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She’an sub-basins. The complex developed at the intersection between two major tectonic boundaries: the Oligo-Miocene AzraqSirhan failed rift, that later developed into the southern Galilee basins and Carmel-Gilboa fault system; and the Dead Sea fault (DSF) plate boundary that developed since the Miocene. Despite numerous studies, KBS still remains one of the enigmatic basin complexes. Its structure, stratigraphy and development are vaguely understood – both inside the basin and in correlation with its surroundings. Our study presents a new and comprehensive 3D model for the structure of KBS complex. It is based on all available gravity measurements, adopted from the national gravity database, and new gravity measurements, collected in cooperation with the Geological Survey of Israel and funded by the Ministry of National Infrastructure, Energy and Water Resources. The gravity data were integr...
Coastal marine systems are experiencing rapid transformations as a result of multiple human-induc... more Coastal marine systems are experiencing rapid transformations as a result of multiple human-induced stressors. Many of these transformations occur at the level of a landscape and as such it is increasingly important to detect changes at these appropriate spatial scales. Remote sensing can be a powerful tool to investigate landscape level changes, but it still requires calibration and ground-truth via field observations. In this research, classification schemes using multispectral and hyperspectral imagery were developed in order to map and monitor temporal changes in the benthos over a fifteen-year period (1999-2014) along the Levant Mediterranean rocky reefs that are made of sandstone (known as Kurkar) and are found along the northern coast of Israel. The Levant Mediterranean rocky reef has been experiencing major temporal shifts in marine biodiversity. These shifts include, but are not limited to, the creation of reefs by large oysters that invaded from the Red Sea, the addition of non-native seaweed species, and over-grazing of seaweed beds by non-native herbivorous fish. Such changes can likely be observed at the landscape level. The bathymetry of the reef is characterized by sandstone ridges that are parallel to the shoreline with emerging islands at their top and a long-shallow channel between the ridge and the shore. Using bathymetric models, a correction for the water attenuation was applied to the spectral dataset and an optical extinction depth was calculated. A recent field campaign (May, 2014) in the study area using acoustic (side scan sonar) and underwater optical measurements provided a ground truth dataset for the study. Decision trees used for the classification were developed based on in situ spectral measurements and underwater video imagery. A time series of seafloor characterization maps was derived from imagery acquired using Itres CASI, Landsat 7 and Landsat 8
Quaternary Science Reviews, 2019
Journal of Applied Geophysics, 2018