Slip rate on the Dead Sea transform fault in northern Araba valley (Jordan (original) (raw)
Related papers
Slip rate on the Deas sea transform fault in northern Araba valley ( Jordan)
The Araba valley lies between the southern tip of the Dead Sea and the Gulf of Aqaba. This depression, blanketed with alluvial and lacustrine deposits, is cut along its entire length by the Dead Sea fault. In many places the fault is well defined by scarps, and evidence for left-lateral strike-slip faulting is abundant. The slip rate on the fault can be constrained from dated geomorphic features displaced by the fault. A large fan at the mouth of Wadi Dahal has been displaced by about 500 m since the bulk of the fanglomerates were deposited 77-140 kyr ago, as dated from cosmogenic isotope analysis (10Be in chert) of pebbles collected on the fan surface and from the age of transgressive lacustrine sediments capping the fan. Holocene alluvial surfaces are also clearly offset. By correlation with similar surfaces along the Dead Sea lake margin, we propose a chronology for their emplacement. Taken together, our observations suggest an average slip rate over the Late Pleistocene of between 2 and 6 mm/yr, with a preferred value of 4 mm/yr. This slip rate is shown to be consistent with other constraints on the kinematics of the Arabian plate, assuming a rotation rate of about 0.396)/Myr around a pole at 31.1°N, 26.7°E relative to Africa.
Late Pleistocene and Holocene slip rate of the northern Wadi Araba fault, Dead Sea transform, Jordan
Journal of seismology, 2001
The Wadi Araba Valley is a morphotectonic depression along part of the Dead Sea Transform (DST) plate boundary that separates the Arabian plate on the east from the Sinai subplate on the west. The Wadi Araba fault (WAF) is one of the main strike-slip faults between the Gulf of Aqaba and the E-W trending Khunayzira (Amatzayahu) fault that bounds the southern end of the Dead Sea. Just south of the Dead Sea, the WAF cuts across several generations of alluvial fans that formed on tributaries to the Wadi Dahal after the regression of Late Pleistocene Lake Lisan ca. 15 ka. Geomorphic and stratigraphic evidence of active faulting, including left-laterally offset stream channels and alluvial-fan surfaces, yielded fault slip-rate data for the northern segment of WAF. Typical cumulative displacements of 54 m, 39 m, and 22.5 m of stream channels and alluvial-fan surfaces across the fault were measured from detailed geologic and topographic mapping. The 54 m offset of the oldest alluvial-fan surface (Q f 1) occurred after the final lowering of Lake Lisan (16-15 ka) and before 11 ka yielding a slip-rate range of 3.4 mm/yr to 4.9 mm/yr. Based on radiocarbon ages of charcoal and landsnail shell samples from the buried Q f 2 alluvial-fan deposits exposed in trenches excavated across the fault, the 39 m and 22.5 m offsets occurred after 9 ka and 5.8 ka, respectively. These data yield a slip-rate range between 3.9 mm/yr and 6.0 mm/yr. The small variability in these slip-rate estimates for different time periods suggests that the northern Wadi Araba fault has maintained a relatively constant slip rate in the past 15 ka. We calculate an average slip rate of 4.7 ± 1.3 mm/yr since 15 ka based on the three separate displacements and age estimates. Five separate offsets of 3 m were measured from gully bends and the offset of small fault-scarp alluvial fans. These displacement data suggest a coseismic slip of 3 m in the last earthquake, or a cumulative slip of 3 m in the past few earthquakes. A maximum slip of 3 m correspond to a Mw 7 earthquake that ruptures about 49 km of fault length. Using an average slip rate of 4.7 ± 1.3 mm/yr together with a 3-m slipper event suggests a maximum earthquake recurrence interval of this fault segment of 500 to 885 years. Table 1. Geologic estimates of lateral slip rates on the Dead Sea transform fault system Fault segment Evidence Amount of Age of Slip rate Authors offset datum DST offset Miocene 40-45 km 7-12 Ma 3.5-6 mm/yr Freund et al., 1968 fault system rocks 7-10 Ma 4-6 mm/yr Freund et al., 1970 3.1-3.7 Ma 9-15 mm/yr Steinitz et al., 1978 Pliocene-7-10 mm/yr Garfunkel Pleistocene et al., 1981 (4-5 Ma) Last 1,000-1.5-3.5 mm/yr Garfunkel 1,500 years (seismic slip rate) et al., 1981 Yammuneh offset Homs basalts 8 km Miocene-5-10 mm/yr Garfunkel fault Pliocene et al., 1981 offset Litani river 5 km 1-2 Ma 5-10 mm/yr South-Central Methodo offset channels 100-150 m post-Lisan 10 mm/yr Garfunkel Jordan fault et al., 1981 Central Wadi offset alluvial fans 3 km 0.3-0.6 Ma 5-10 mm/yr Garfunkel Araba fault et al., 1981 DST fault offset of E-W 2.1 mm 817 years ∼ 2.5 mm/yr Marco et al., (Hula area) trending walls in the 1997 Crusader Ateret Fortress Southern Wadi offset alluvial fans 150 m 20-23 ka 7.5 mm/yr Zak and Freund, Araba fault 1966 Arava fault offsets in 15 km Late Pliocene 3-7.5 mm/yr Ginat et al., drainage basins and or early 1998 alluvial fans Pleistocene Northern Wadi slumps 6.4 mm/yr El-Isa and Mustafa, Araba fault in Lisan deposits (seismic slip rate) 1986 Northern Wadi offset of the late 500 m 77-140 ka 2-6 mm/yr Klinger et al., Araba fault Pleistocene Dahal preferred rate 2000a alluvial fan of 4 mm/yr Northern Wadi offset gullies and 54 m 16-11 ka 3.4-4.9 mm/yr Niemi et al., Araba fault fan surfaces on 39 m 9-6.5 ka 4.3-6.0 mm/yr this paper tributaries to Wadi 22.5 m 5.8 ka 3.9 mm/yr Dahal avg. 4.7±1.3 mm/yr
A 48-kyr-long slip rate history for the Jordan Valley segment of the Dead Sea Fault
Earth and Planetary Science Letters, 2007
We investigate the late Quaternary active deformation along the Jordan Valley segment of the left-lateral Dead Sea Fault and provide new insights on the behaviour of major continental faults. The 110-km-long fault segment shows systematic offsets of drainage systems surveyed at three sites along its southern section. The isotopic dating of six paleoclimatic events yields a precise chronology for the onset of six generations of gully incisions at 47.5 ka BP, 37.5 ka BP, 13 ka BP, 9 ka BP, 7 ka BP, and 5 ka BP. Additionally, detailed mapping and reconstructions provide cumulative displacements for 20 dated incisions along the fault trace. The individual amounts of cumulative slip consistently fall into six distinct classes. This yields: i) an average constant slip rate of 4.7 to 5.1 mm/yr for the last 47.5 kyr and ii) a variable slip rate ranging from 3.5 mm/yr to 11 mm/yr over 2-kyr-to 24-kyr-long intervals. Taking into account that the last large earthquake occurred in AD 1033, we infer 3.5 to 5 m of present-day slip deficit which corresponds to a Mw ∼7.4 earthquake along the Jordan Valley fault segment. The timing of cumulative offsets reveals slip rate variations critical to our understanding of the slip deficit and seismic cycle along major continental faults.
Tectonics, 2012
1] The Dead Sea strike-slip fault accommodates the northward motion of Arabia relative to Sinai at a rate of 5mm/yr.Thesouthernsegmentofthefault,theWadiArabafault,runsalongavalleyblanketedinQuaternarysediments.Wefirstfocusedonunderstandingtherelativeandabsolutetimingofemplacementofthealluvialsurfaces.WethendeterminedtheprobablesourceofthesedimentsbeforeassessingtheirlateraloffsettoconstrainthelatePleistocenefaultsliprate.Sevensuccessivemorphostratigraphiclevelswereidentified.Attwosites,werecognizedanalluvialsequenceoffivetosevensuccessivelevelswithagesgettingyoungernorthward,apatternconsistentwiththewesternblockmovingsouthwardrelativetotwofixedfeedingchannelslocatedtotheeast.Surfacesampleswerecollectedfor10Becosmogenicradionuclidedating.FansF3andF5werefoundtobesynchronousfromsitetosite,at102AE26kaand324AE22ka,respectively,whileF4couldbedatedat163AE19kaatonesiteonly.Theseareminimumages,assumingnoerosionofthealluvialsurfaces.Atleasttwooftheseperiodsarecorrelatedwithwetperiodsthatareregionallywelldocumented.Furtheranalysesoftectonicoffsetsareaffectedinmostcasesbylargeuncertaintiesduetotheconfigurationofthesites.Theyindicatemaximumoffsetsof5 mm/yr. The southern segment of the fault, the Wadi Araba fault, runs along a valley blanketed in Quaternary sediments. We first focused on understanding the relative and absolute timing of emplacement of the alluvial surfaces. We then determined the probable source of the sediments before assessing their lateral offset to constrain the late Pleistocene fault slip rate. Seven successive morphostratigraphic levels were identified. At two sites, we recognized an alluvial sequence of five to seven successive levels with ages getting younger northward, a pattern consistent with the western block moving southward relative to two fixed feeding channels located to the east. Surface samples were collected for 10 Be cosmogenic radionuclide dating. Fans F3 and F5 were found to be synchronous from site to site, at 102 AE 26 ka and 324 AE 22 ka, respectively, while F4 could be dated at 163 AE 19 ka at one site only. These are minimum ages, assuming no erosion of the alluvial surfaces. At least two of these periods are correlated with wet periods that are regionally well documented. Further analyses of tectonic offsets are affected in most cases by large uncertainties due to the configuration of the sites. They indicate maximum offsets of 5mm/yr.Thesouthernsegmentofthefault,theWadiArabafault,runsalongavalleyblanketedinQuaternarysediments.Wefirstfocusedonunderstandingtherelativeandabsolutetimingofemplacementofthealluvialsurfaces.WethendeterminedtheprobablesourceofthesedimentsbeforeassessingtheirlateraloffsettoconstrainthelatePleistocenefaultsliprate.Sevensuccessivemorphostratigraphiclevelswereidentified.Attwosites,werecognizedanalluvialsequenceoffivetosevensuccessivelevelswithagesgettingyoungernorthward,apatternconsistentwiththewesternblockmovingsouthwardrelativetotwofixedfeedingchannelslocatedtotheeast.Surfacesampleswerecollectedfor10Becosmogenicradionuclidedating.FansF3andF5werefoundtobesynchronousfromsitetosite,at102AE26kaand324AE22ka,respectively,whileF4couldbedatedat163AE19kaatonesiteonly.Theseareminimumages,assumingnoerosionofthealluvialsurfaces.Atleasttwooftheseperiodsarecorrelatedwithwetperiodsthatareregionallywelldocumented.Furtheranalysesoftectonicoffsetsareaffectedinmostcasesbylargeuncertaintiesduetotheconfigurationofthesites.Theyindicatemaximumoffsetsof5.5 km for the oldest, possibly $1 Ma old, surfaces. They lead to bracketing of the fault slip rate between 5 and 12 mm/yr, with preferred values of 5-7 mm/yr, for the last 300 ka. Citation: Le Béon, M., Y. Klinger, A.-S. Mériaux, M. Al-Qaryouti, R. C. Finkel, O. Mayyas, and P. Tapponnier (2012), Quaternary morphotectonic mapping of the Wadi Araba and implications for the tectonic activity of the southern Dead Sea fault, Tectonics, 31, TC5003,
Journal of Geophysical Research, 2010
1] Two sites located along the Wadi Araba Fault (WAF) segment of the Dead Sea Fault are targeted for tectonic-morphological analysis. 10 Be cosmogenic radionuclide (CRN) dating of embedded cobbles is used to constrain the age of offset alluvial surfaces. At the first site a 48 ± 7 m offset alluvial fan, for which 10 Be CRN model ages average 11.1 ± 4.3 ka, yield a slip rate of 5.4 ± 2.7 mm/a, with conservative bounds of 1.3-16.4 mm/a. At the second site the scattered distributions of the 10 Be CRN ages from an offset bajada attest to the complex processes involved in sediment transport and emplacement. There, two offsets were identified. The 160 ± 8 m offset of an incised alluvial fan dated at 37 ± 5 ka shows a slip rate of 4.5 ± 0.9 mm/a, with a conservative minimum value of 3.2 mm/a. A larger offset, 626 ± 37 m, is derived from a prominent channel incised into the bajada. Cobbles from the bajada surface have ages from 33 to 141 ka, with a mean of 87 ± 26 ka. A slip rate of 8.1 ± 2.9 mm/a is derived from the mean age, with conservative bounds of 3.8-22.1 mm/a. These results and other published slip rates along the linear WAF segment, from GPS to geological time scales, lack the resolution to fully resolve the question of temporal variations versus consistency of the fault slip rate of the WAF. Yet, given the uncertainties, they are not inconsistent with each other.
2010
1] Two sites located along the Wadi Araba Fault (WAF) segment of the Dead Sea Fault are targeted for tectonic-morphological analysis. 10 Be cosmogenic radionuclide (CRN) dating of embedded cobbles is used to constrain the age of offset alluvial surfaces. At the first site a 48 ± 7 m offset alluvial fan, for which 10 Be CRN model ages average 11.1 ± 4.3 ka, yield a slip rate of 5.4 ± 2.7 mm/a, with conservative bounds of 1.3-16.4 mm/a. At the second site the scattered distributions of the 10 Be CRN ages from an offset bajada attest to the complex processes involved in sediment transport and emplacement. There, two offsets were identified. The 160 ± 8 m offset of an incised alluvial fan dated at 37 ± 5 ka shows a slip rate of 4.5 ± 0.9 mm/a, with a conservative minimum value of 3.2 mm/a. A larger offset, 626 ± 37 m, is derived from a prominent channel incised into the bajada. Cobbles from the bajada surface have ages from 33 to 141 ka, with a mean of 87 ± 26 ka. A slip rate of 8.1 ± 2.9 mm/a is derived from the mean age, with conservative bounds of 3.8-22.1 mm/a. These results and other published slip rates along the linear WAF segment, from GPS to geological time scales, lack the resolution to fully resolve the question of temporal variations versus consistency of the fault slip rate of the WAF. Yet, given the uncertainties, they are not inconsistent with each other.
Stephan Mueller Special Publication Series, 2001
Detailed stratigraphic and structural study of the southeast Dead Sea basin along the Dead Sea Transform in Jordan was carried out in order to determine the deformation history and processes of pullapart basin formation. Fieldwork focused on mapping and collecting structural orientation data in the area of the intersection of the NE-trending, strike-slip Wadi Araba fault (WAF) and the NW-trending, dip-slip Khunayzira fault. The recent movement on the WAF shows spectacular polished fault planes, slickensides, and Riedel and conjugate Riedel shears. During the Late Quaternary the position of the WAF shifted west toward the basin. This is evident from a series of pressure ridges and exposed positive flower structures that do not deform the lacustrine deposits of the Lisan formation (63-15 ka). The Khunayzira fault makes a prominent, curvilinear 50 m-high scarp that trends SE-NW. In the study area, the scarp is highly eroded and sinuous. Slip on the Khunayzira fault branches onto four fault traces near the junction with the WAF. No cross-cutting relationship is observed between the Khunayzira and WAF. These data contradict the idea that strike-slip motion on the WAF terminates and is transferred to dip slip along the Khunayzira fault. Our data agree with the more complex model of the Dead Sea pull-apart basin, that explain the activity of the transverse faults as younger than the formation of the basin. Paleostress calculations based on fault-slip data of the WAF and the faults of the Upper Cretaceous rock show two stress fields. The first is characterized by WNW compression and NNE tension, which represent the Syrian Arc stress field. The second is characterized by NNW compression and ENE tension, which represents the Dead Sea stress field.
Tectonic evolution in the Wadi Araba Segment of the Dead Sea Rift, South-West Jordan
Stephan Mueller Special Publication Series, 2001
This work presents the first palaeostress results obtained from fault-slip data along the eastern margins of the Dead Sea Rift (also named Dead Sea Transform) in South-western Jordan. Stress inversion of the fault-slip data was performed using an improved Right-Dieder method, followed by rotational optimisation. Fault-slip data (totalling 2773) include fault planes, striations and sense of movements, obtained from outcrops ranging in age from Neoproterozoic crystalline basement to Holocene sediments. The data were inverted to determine 88 different palaeostress tensors. Eight palaeostress tensor groups (stages) have been identified, ranging from the Late Neoproterozoic to the Holocene period, and have been correlated with the tectonic evolution of the Dead Sea Rift.