التفاصيل البيبلوغرافية
| العنوان: |
Synchronous onset of the Messinian salinity crisis and diachronous evaporite deposition: New evidences from the deep Eastern Mediterranean basin. |
| المؤلفون: |
Manzi, V.1,2 (AUTHOR) vinicio.manzi@unipr.it, Gennari, R.2,3 (AUTHOR), Lugli, S.4 (AUTHOR), Persico, D.1 (AUTHOR), Roveri, M.1,2 (AUTHOR), Gavrieli, I.5 (AUTHOR), Gvirtzman, Z.5,6 (AUTHOR) |
| المصدر: |
Palaeogeography, Palaeoclimatology, Palaeoecology. Dec2021, Vol. 584, pN.PAG-N.PAG. 1p. |
| مصطلحات موضوعية: |
*SALINITY, *NANNOFOSSILS, *CYCLOSTRATIGRAPHY, *SALT mining, *EVAPORITES, *CRISES |
| مصطلحات جغرافية: |
MIDDLE East |
| الشركة/الكيان: |
UNITED States. Federal Bureau of Investigation |
| مستخلص: |
We present a basin-wide correlation of the pre-evaporitic succession across the deep Levant basin, based on integrated bio- and cyclostratigraphy. The onset of Messinian salinity crisis (MSC) can be placed in all studied wells where foraminifers suddenly disappear and normal marine calcareous nannofossils are replaced by opportunistic assemblages. These changes mark the base of the Foraminifers Barren Interval (FBI), a 10s-of-m-thick (below seismic resolution), evaporite-free, shale unit that records the entire duration of the first stage. Moving towards the basin margin the FBI is progressively truncated on top by the Messinian erosional surface (MES), a regional-scale discontinuity sealed by a thin clastic evaporite units overlain by thick halite deposits. Our results confirm previous hypothesis suggesting that the crisis started in deep- as well as in shallow-water settings at 5.97 Ma and pointing to a synchronous onset of the MSC but diachronous deposition of evaporites. During stage 1 of the crisis, coeval with gypsum deposition in marginal basins, the salinity in deep basins progressively increased (with possible oxygen reduction) hindering the life of marine organisms. Then, at 5.60 Ma, when salinity in deep basins exceeded halite saturation, massive halite precipitation started, and a nearly 2-km-thick salt sequence accumulated in deep basins within a short period of 60 kyr. At that time (stage 2), sedimentation rate jumped by an order of magnitude reaching a few cm/yr. Similar sedimentation rates are inferred for the Realmonte salt mine (Sicily) and observed in the modern Dead Sea and artificial salinas. • The onset of the Messinian salinity crisis was synchronous at 5.97 Ma. • In the deep Levant basin the onset is marked by the disappearance of marine biota. • Evaporite-free shales barren in foraminifers record stage 1 of the crisis. • The evaporite succession started to accumulate in deep settings only since stage 2. • A regional-scale unconformity marks the base of the evaporites. [ABSTRACT FROM AUTHOR] |
| قاعدة البيانات: |
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