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Biochar production from organic waste offers an important alternative for waste management, also improves soil properties (bio-physico-chemical) and reduces heavy metal pollution risk caused by the...

Incision by the River Euphrates has created a dramatic erosional landscape in the northern Arabian Platform in SE Turkey. We obtain accurate heights of its terrace deposits in the Birecik area using differential GPS, and summarise evidence regarding heights of Late Miocene basalt flows and low-altitude wetland sediments. We thus estimate ∼600 m of uplift since the early Late Miocene (∼9 Ma), represented by ∼270 m of fluvial incision, the difference reflecting downstream channel-lengthening as the coastline has retreated to the Persian Gulf, ∼1400 km away. The oldest recognised sediments, inset below this level, form a thick aggradation between ∼100 and ∼130 m above the present level of the Euphrates. We estimate that this accumulated during ∼5–3 Ma when uplift rates were low, such that aggradation was necessary to maintain a downstream channel gradient in response to the coastal retreat. Palaeolithic artefacts have been reported locally in Euphrates deposits up to ∼80 m above present river level, which we tentatively date to ∼1.8 Ma. The Euphrates subsequently incised to within ∼10 m of its present level before aggrading ∼45 m higher in the late Early Pleistocene. The final ∼55 m of incision reflects the increase in uplift rates observed worldwide in the early Middle Pleistocene, following the Mid-Pleistocene Revolution.

We present the first overall synthesis of the terrace deposits of the River Euphrates in SE Turkey, northern Syria, and western Iraq, combining new observations with summaries of data sets from different reaches that had previously been independently studied on a piecemeal basis. The largest number of terraces observed in any reach of the Euphrates is 11, in western Iraq, where this river leaves the uplands of the Arabian Platform. In many other localities not more than 5 or 6 terraces have previously been identified, although we infer that some of these are resolvable into multiple terraces. These terraces are typically formed of gravel, principally consisting of Neotethyan ophiolite and metamorphic lithologies transported from Anatolia. Although older gravels are also evident, most of the Euphrates terrace deposits appear, given the chronologies that have been established for different parts of the study region, to date from the late Early Pleistocene onwards, the cold stages most often represented being interpreted as marine Oxygen Isotope Stages 22, 16, 12, 8, 6 and/or 4, and 2. The formation of this terrace staircase reflects regional uplift of the Arabian Platform. Estimated amounts of uplift since the Middle Pliocene decrease southeastward from almost 300 m in SE Turkey to ∼150 m in western Iraq. Uplift rates increased in the late Early Pleistocene, the uplift estimated since then decreasing from ∼110 m in SE Turkey to a minimum of ∼50 m in the Syria–Iraq border region, then increasing further downstream across western Iraq to ∼70 m. Numerical modelling of this uplift indicates a relatively thin mobile lower-crustal layer, consistent with the low surface heat flow in the Arabian Platform.