Trend Assessment of Global, UVB, UVA Irradiation and Dry Bulb Temperature at the Lowest Terrestrial Site on Earth: Dead Sea, Israel

The Dead Sea basin is lowest terrestrial site on the globe. A meteorological station monitoring the global, UVB and UVA irradiation and the dry bulb temperature was established in 1995 in conjunction with a study of bio-climatological properties of the region with regard to photoclimatherapy treatment of dermatological diseases. The availability of such irradiation and dry bulb temperature databases has been utilized to perform a study to determine if any trends regarding either irradiation or dry bulb temperature exist at this unique site. There was no indication of any trends, based upon a p-value analysis, regarding the global, UVB and UVA irradiation. The global irradiation database included the time interval 1995-2020; whereas the corresponding time interval for the UVB and UVA irradiation databases was 1995-2018. The dry bulb temperature database consisted of the time interval 1995-2020 and, once again, no trends were observed throughout the year with the exception of the nocturnal time interval, between 18:00 to 06:00, during the month of October which exhibited a warming trend of 0.78°C/decade

A new approach to constrain the seismic origin for prehistoric turbidites as applied to the Dead Sea Basin

<p>Seismogenic turbidites are widely used for geohazard assessment. The use of turbidites as an earthquake indicator requires a clear demonstration that an earthquake, rather than non-seismic factors, is the most plausible trigger. The seismic origin is normally verified either by correlating the turbidites to historic earthquakes, or by demonstrating synchronous deposition over large areas of a basin. Correlating historic earthquakes could potentially constrain the seismic intensities necessary for triggering turbidites, however this method is not applicable to prehistoric events. In addition, the synchronous deposition of turbidites cannot be verified for a single core record.</p><p>Here, we propose a new approach to establish the seismic origin of prehistoric turbidites that involves analyzing in situ deformation that underlies each turbidite, as recorded in a 457 m-long core from the Dead Sea depocenter. These in situ deformations have been previously verified as seismites and could thus authenticate the trigger for each overlying turbidite. We also constrain the seismic intensities that triggered prehistoric turbidites by analyzing the degree of in situ deformation underlying each turbidite. Moreover, our high-resolution chemical and sedimentological data validate a long-lasting hypothesis that soft-sediment deformation in the Dead Sea formed at the sediment-water interface. In addition, we use our results to propose seven basic earthquake-related depositional scenarios preserved in depocenters located in tectonically active regions like the Dead Sea. These techniques and findings permit a more confident geohazard assessment in the region and act as a model for other similar tectonic settings, by improving the completeness of a paleoseismic archive.</p>

Cyclophosphates, a new class of native phosphorus compounds, and some insights into prebiotic phosphorylation on early Earth

Cyclophosphates are a class of energy-rich compounds whose hydrolytic decomposition (ring opening) liberates energy that is sufficient for initiation of biomimetic phosphorylation reactions. Because of that, cyclophosphates might be considered as a likely source of reactive prebiotic phosphorus on early Earth. A major obstacle toward adoption of this hypothesis is that cyclophosphates have so far not been encountered in nature. We herein report on the discovery of these minerals in the terrestrial environment, at the Dead Sea basin in Israel. Cyclophosphates represent the most condensed phosphate species known in nature. A pathway for cyclophosphate geosynthesis is herein proposed, involving simple pyrolytic oxidation of terrestrial phosphides. Discovery of natural cyclophosphates opens new opportunities for modeling prebiotic phosphorylation reactions that resulted in the emergence of primordial life on our planet.