Origin and kinematics of a basin-scale, non-polygonal, layer-bound normal fault system in the Levant Basin, eastern Mediterranean

Polygonal, layer-bound normal faults can extend over very large areas (>2,000,000 km2) of sedimentary basins. Best developed in very fine-grained rocks, these faults are thought to form during early burial in response to a range of diagenetic processes, including compaction and water expulsion. Local deviations from this idealised polygonal pattern are common; however, basin-scale, layer-bound faults with non-polygonal map view are not well-documented and accordingly, their genesis is not well understood. In this study, we use 3D seismic reflection data, biostratigraphy and well logs from the Southern Levant Basin, offshore Israel, to develop an age-constrained seismic-stratigraphic framework and determine the geometry and kinematics of such basin-scale fault system. The faults tip out downwards along an Eocene Unconformity, but unlike layer-bound faults in the Northern Levant Basin, they do not reach the base of the Messinian evaporites, instead tipping out upwards at the top Langhian. On average, the faults in the Southern Levant Basin are 6.3 km long, have an average throw of 120 m, and consistently strike NW-SE. Throw-depth plots, accompanied by thickness changes, indicate that the faults accumulated growth strata during the Late Burdigalian and are spatially and kinematically associated with a WSW-ESE-striking strike-slip fault. Unlike true polygonal faults, these faults propagated through ca. 2 km-thick sandstone-prone Oligocene-Miocene strata. Whereas previous studies from the Northern Levant Basin associate fault nucleation and growth with burial-related diagenesis, the sandstone-prone character of the Oligocene-Miocene suggests that this process cannot be readily applied to the Southern Levant Basin. Instead, we highlight potential tectonic events that occurred during and may have triggered thin-skinned extension at times of fault growth

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Late Paleocene to middle Eocene carbon isotope stratigraphy of the Northern Negev, Southern Israel: potential for paleoclimate reconstructions

Sedimentary records depicting significant variability in climate and carbon cycling across the early Paleogene have emerged over the last two decades. Continuous, long-term, high-resolution records mostly derive from deep-sea drill cores, and only few derive from continental margin locations. Here we examine lower Paleogene marls and chalks collected from a core (RH-323) in the Northern Negev Desert (Southern Israel). The studied sediments accumulated on a continental slope of the southern Tethys at ~500–700 m paleodepth and did not undergo deep burial. We analyzed bulk carbonate stable carbon and oxygen isotopes and bulk magnetic susceptibility. The resulting records can be aligned with those from elsewhere and include the Paleocene Carbon Isotope Maximum (PCIM), Paleocene Eocene Thermal Maximum (PETM) and Early Eocene Climatic Optimum (EECO). An obvious realization is a concurrence between local lithological variations and major climate and carbon cycle changes. This has been highlighted for sedimentary sequences elsewhere, but the relations differ in the Negev, such that carbonate rich intervals mark the PCIM and PETM, and a transition from marl to chalk initiates the EECO. Overall, the relatively pristine and immature sediment records in southern Israel likely provide potential for high-resolution paleoclimate and carbon cycle reconstructions during a crucial time interval and in a crucial part of the world