5 research outputs found
Low-temperature thermochronology of francolite: Insights into timing of Dead Sea Transform motion
Cambrian siliciclastic sequences along the Dead Sea Transform (DST) margin in southern Israel and southern Jordan host both detrital fluorapatite [Dâapatite] and Uârich authigenic carbonateâfluorapatite (francolite) [Aâapatite]. Dâapatite and underlying Neoproterozoic basement apatite yield fission track (FT) data reflecting PaleozoicâMesozoic sedimentary cycles and epeirogenic events, and dispersed (UâThâSm)/He (AHe) ages. Aâapatite, which may partially or completely replace Dâapatite, yields an early Miocene FT age suggesting formation by fracturing, hydrothermal fluid ascent and intraâstrata recrystallisation, linked to early DST motion. The DST, separating the African and Arabian plates, records ~105 km of sinistral strikeâslip displacement, but became more transtensional postâ5 Ma. Helium diffusion measurements on Aâapatite are consistent with thermally activated volume diffusion, indicating Tc ~52â56±10°C (cooling rate 10°C/Myr). Aâapatite AHe data record Pliocene cooling (~35â40°C) during the transtensional phase of movement. This suggests that timing of important milestones in DST motion can be discerned using Aâapatite lowâtemperature thermochronology data alone
Low-temperature thermochronology of francolite: Insights into timing of Dead Sea Transform motion
Cambrian siliciclastic sequences along the Dead Sea Transform (DST) margin in southern Israel and southern Jordan host both detrital fluorapatite [Dâapatite] and Uârich authigenic carbonateâfluorapatite (francolite) [Aâapatite]. Dâapatite and underlying Neoproterozoic basement apatite yield fission track (FT) data reflecting PaleozoicâMesozoic sedimentary cycles and epeirogenic events, and dispersed (UâThâSm)/He (AHe) ages. Aâapatite, which may partially or completely replace Dâapatite, yields an early Miocene FT age suggesting formation by fracturing, hydrothermal fluid ascent and intraâstrata recrystallisation, linked to early DST motion. The DST, separating the African and Arabian plates, records ~105 km of sinistral strikeâslip displacement, but became more transtensional postâ5 Ma. Helium diffusion measurements on Aâapatite are consistent with thermally activated volume diffusion, indicating Tc ~52â56±10°C (cooling rate 10°C/Myr). Aâapatite AHe data record Pliocene cooling (~35â40°C) during the transtensional phase of movement. This suggests that timing of important milestones in DST motion can be discerned using Aâapatite lowâtemperature thermochronology data alone