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The River Nile forms the fertile corridor that links its headwaters in equatorial Africa to its delta in the Mediterranean (Fig. 1)1. An understanding of its evolution through the Holocene is pivotal to discussions of fluvial system dynamics and ancient cultural development, which both occurred against a backdrop of major hydroclimatic change: that is, the shift from the ‘Green Sahara’ of the African Humid Period (~14.5–5.0 thousand years ago (ka))2,3,4,5 to the present hyper-arid Sahara Desert6,7. The present understanding of the Egyptian Nile’s response to climate change relies heavily on data gathered from its delta8,9, its offshore Mediterranean deep-sea fan4,10,11,12,13 and the Fayum depression14. Few studies have focused on the fluvial domain itself15,16,17, and very little is known about the Holocene development of the Egyptian Nile Valley18,19,20,21 despite its central role in ancient Egyptian history22,23. Furthermore, previous research on the Egyptian Nile is often lacking detailed chronostratigraphic and sedimentological data that make existing reconstructions highly uncertain and inconsistent22,24.

Fig. 1: Geomorphic map of the Nile Valley near Luxor, Egypt.
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Smaller black dots mark borehole locations; larger black dots mark OSL-dated core sites and are labelled with Roman numerals. a–f, Key archaeological sites: Karnak Temple complex (a), Luxor Temple (b), Medinet Habu (c), Kom el-Hettân (d), Ramesseum (e) and Valley of the Kings (f). The inset map shows the Nile Basin (dark grey) in Northeast Africa, its drainage system (blue) and the Egyptian Nile Valley (black). Methods provide more OSL dating details, and Extended Data Tables 1 and 3 provide cross references with original core-site numbering. Med., Mediterranean. Figure created using ArcGIS Pro. Credit: background World Imagery Basemap, Esri.

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To address this knowledge gap, a transect of 81 boreholes spanning the Nile Valley (~10 km wide) was drilled near Luxor (ancient Thebes) in Upper Egypt (Fig. 1). Sedimentary information from these cores (average depth ~8 m) (Supplementary Data 1) was used to study key changes in the riverine landscape, which are pinned in time by 48 optically stimulated luminescence (OSL) ages (Extended Data Figs. 1–4 and Extended Data Tables 1–4). This approach provides a unique and vital understanding of the Holocene Egyptian Nile system and its responses to climate change at a focal region of ancient Egyptian culture. Our area of investigation includes UNESCO World Heritage sites such as the Karnak and Luxor temples located east of the present Nile (Fig. 1) and the royal cult temples and necropoleis on the western desert margin—places that were both physically and mythologically connected to the fluvial landscape25,26. In addition, it is possible that the changing environment also impacted the regional agro-economy, which was of critical importance to the success of the ancient Egyptian state27,28.

Our study shows how the floodplain environment changed dramatically during the Dynastic Period (~5.1–2.4 ka) (Extended Data Table 5) and how the environmental canvas on which ancient culture developed, thrived and declined was reshaped. We introduce a framework for the Egyptian Nile near Luxor, while also filling in the looming gap in hydroclimatic information that exists between upstream and downstream locations within the Nile Basin29.

Sedimentary architecture of Holocene Egyptian Nile Valley

At various levels in the subsurface along our transect near Luxor, the borehole data reveal basal, sandy deposits, which are interpreted as fluvial terraces (units T1–4; Fig. 2 and Table 1). These erosional terraces are the result of long-term semi-continuous valley-wide fluvial incision and contraction during the first half of the Holocene. Subsequently, a shift occurred to a fast-aggrading Nile system during the remainder of the Holocene, whose deposits blanketed the earlier terrace morphology. Multiple channel belts (units CB1–3b) and a laterally expanding floodplain (unit FP1) are associated with this more recent phase of fluvial aggradation and valley expansion.

Fig. 2: Sedimentary architecture of the Holocene Nile Valley near Luxor, Egypt.
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Figure 1 provides transect and OSL-dated core-site locations. OSL ages are shown with only one decimal for legibility; Methods and Extended Data Figs. 1–4 and Tables 1-4 provide a comprehensive account of the OSL dating. Table 1 provides sedimentary descriptions and facies interpretation of each geogenetic unit. W, west; E, east; +m.s.l., above mean sea level.

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Table 1 Overview of geogenetic units in the Holocene Nile Valley near Luxor, Egypt
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The oldest terrace (T1; Fig. 2 and Table 1) is dated to 9.42 ± 0.75 ka and forms the oldest present-day exposed surface at the eastern valley margin at an elevation of ~78.5 m above mean sea level. Westward, buried underneath ~1 m of younger alluvium, the top of terrace T2 lies at ~75 m and is dated to 8.85 ± 0.66 ka. Further towards the centre of the valley, the top of terrace T3, at 70–72 m, is dated to 4.54 ± 0.42 ka; a small remnant of T3 is also preserved at the West Bank’s desert edge. The youngest terrace, T4, at 66–68 m, is dated to 4.09 ± 0.31 ka and is only found on the West Bank. This terrace forms the substrate from which fluvial aggradation initiated and thus marks an important turning point in the fluvial history of the Nile Valley.

Three channel belts (CB1–3) can be distinguished in the transect (Fig. 2 and Table 1), with (the end of) their activity dated to 3.34 ± 0.27 ka (CB1), 2.81 ± 0.21 ka (CB2) and 0.11 ± 0.01 ka (CB3) respectively. CB3b comprises the present-day Nile. CB1 is 500–600 m wide and corresponds in age and geometry with a previously studied secondary river channel on the Theban West Bank26,30. CB2 measures ~1,200 m across and so may have carried the Nile’s full discharge. CB3 is ~1,800 m wide and was partially abandoned during the first half of the twentieth century31. The modern Nile belt (CB3b) is 600–750 m wide. Its channel is presently entrenched by 2–3 m, probably in response to sediment deprivation due to the construction of the Aswan High Dam in the 1960s.

Floodplain deposits (FP1; Table 1) blanket both banks, varying in thickness between 1 and 1.5 m in the east to ~9.5 m in the west (Fig. 2). Eight OSL ages at core-site VII determined floodplain sedimentation rates at ~12 mm per year around 3.4 ka (that is, New Kingdom age; Extended Data Table 5), whereas rates of the last three millennia were substantially lower at ~2 mm per year (Extended Data Fig. 5).

Hydroclimatic impact on the Nile’s evolution

Our research reveals a major shift in the Nile’s fluvial system behaviour, a turning point largely unrecognized in its phasing, time frame and mechanism in previous Nile river dynamics models22,23,29 and adds to other studies that have inferred Holocene deposition19,24,28. We found a sequence of channel entrenchment and contraction during the Early and Middle Holocene (Fig. 3a–d) that completely reverts to valley-wide fluvial aggradation around 4 ka (Figs. 3e–h and 4a), potentially coinciding with the 4.2 ka climate event32. Such system changes are usually related to a (combination of) substantial increase in sediment supply, sediment fining and/or a decrease in discharge33, forced by changes in the hydroclimate regime.

Fig. 3: Schematic reconstruction of the Holocene evolution of the Nile River near Luxor, Egypt.
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a–d, During the Early and Middle Holocene (a), Epipalaeolithic deposits were incised by ~3.5 m during the Late Epipalaeolithic (b), which were subsequently incised by 3–5 m during the Old Kingdom (c) and again during the Middle Kingdom (d) by another 2–4 m, forming the Nile Valley’s substrate, while consistently narrowing its active floodplain at each erosional step. e–g, From the New Kingdom (e) onward, fluvial aggradation and channel belt formation starts and continued during the Third Intermediate Period (f) until the mid-twentieth century (g) when upstream dam construction started to reduce sediment supply. h, Until recently, the Nile River managed to gradually build up and enlarge its floodplain, eventually spanning almost its entire valley. Egyptian cultural periods: Extended Data Table 5; ages (ka): Table 1.

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Fig. 4: Synthesis of the Egyptian Nile Valley’s fluvial evolution in relation to hydroclimatic changes in the Nile Basin.
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a, Nile Valley floodplain incision and aggradation levels (this study). b, Summer insolation (June, July, August (JJA)) at 15° N (ref. 48) as indicator for monsoon strength. c, Duration of the African Humid Period (AHP)3; peak AHP4. d,e, Hydrogen isotope record from leaf waxes (δDwax) as proxy for precipitation variation in the Lake Victoria basin (d)35 and the Ethiopian Highlands (Lake Dendi)36 (e). f, Globigerinoides ruber oxygen isotope as a proxy for Nile discharge recorded on its deep-sea fan. MS21PC: central deep-sea fan; PS009PC: eastern deep-sea fan12. g, Blue/white Nile provenance in deep-sea fan sediments11. h, Fluvial planform of the Nile River near Luxor (this study). i–k, Sedimentation rates (mm yr−1) for the Nile deep-sea fan11 (i), spatially averaged values for the northern Nile Delta45 (j) and average rates for the Nile Valley near Luxor (k) (this study; Extended Data Fig. 5). l, North African (10–28° N) palaeohydrological lake records as proxy for humidification and aridification of the Sahara and Sahel regions34. m, Eastern Mediterranean Sapropel S1a/b49. Egyptian cultural periods: Extended Data Table 5.

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The changes observed here in the Egyptian Nile’s Holocene riverine landscape near Luxor are in line with observations of their drivers (Fig. 4b–g), evidence for which is found elsewhere in the Nile Basin. From ~11.5 ka onward, wet conditions existed over northern Africa (Fig. 4d,e,l)6,7,34,35,36, due to a northern position of the Intertropical Convergence Zone4, which resulted in increased Nile discharge enlarging its erosivity and transport capacity (Fig. 4f)11,12,13,37. Wetter conditions also led to a denser vegetative cover6,7, reducing upstream sediment input (Fig. 4g)11,12,38. The observed erosion and subsequent uptake of sediment in the Nile Valley through channel incision was, therefore, probably a direct result of the wetter Early Holocene Nile Basin’s hydroclimatic regime.

Conversely, rapid aggradation and formation of CB1–3b in the Nile Valley from ~4 ka onward is thought to have been triggered by a diminishing discharge (and hence erosion capacity) and an increase in (fine) sediment supply11,12,17,39. The driving factor behind this increase was the progressive aridification of the Nile Basin, especially between 5 and 6 ka (Fig. 4c,l)3,6,34,40, which, potentially in combination with changing human impact on the hinterland41,42,43, made soils increasingly prone to erosion44.

This major shift in the Nile’s system led to progressive changes in the fluvial planform of the Egyptian Nile near Luxor (Fig. 4h), from a dynamic wandering-braided system (T1–4) during its incisive phase (~11.5–4 ka), to less-dynamic anabranching straight channels (CB1–2 and CB3’s predecessor) during its transition (~4–2 ka) (Fig. 3e,f) and the present single-thread system (CB3(b)) during its most recent phase (~2 ka–present) (Fig. 3g,h). The large input of fine sediment promoted cohesive bank and floodplain formation, enhancing their erosion-resistance and progressively securing the low-gradient channels (CB1–3) in their position. Limited migration facilitated the build-up of natural levees and increased the elevation difference with the backswamp areas. This led to rearrangement of the Egyptian Nile’s channel configuration in an avulsive manner following levee breaches during high flood stages21,26, rather than gradual lateral migration as has been previously suggested for the presumed meandering Egyptian Nile system22,23.

On a supraregional scale, these changing hydroclimatic conditions led to increased fluvial dynamics, and in combination with sea-level rise in the Mediterranean8,9, resulted in the onlap of alluvium and creation of floodplains in downstream regions from 7–8 ka ago. Over time, the Nile’s depocentres shifted progressively upstream, from the Nile’s deep-sea fan all the way up to Upper Egypt, implying diachronous onsets in aggradation (Fig. 4i–k) and basically backfilling its valley. The increase in sediment supply, in combination with a reduction in discharge, and helped by a deceleration of Late Holocene sea-level rise, will have accelerated the upstream movement of the location where the river started to aggrade.

Before ~8 ka, most of the sedimentation occurred on the western deep-sea fan, with records showing accumulation rates of >1 mm per year (Fig. 4i)10,11. From ~8–5.5 ka, sedimentation on the deep-sea fan notably slowed down, whereas the Nile Delta started to build up at rates of >2 mm per year (Fig. 4j)9. Here the erosion upstream in the Nile Valley, together with rising Holocene sea levels, led to enhanced aggradation9,45. From ~5.5–4 ka, sedimentation on the Nile’s deep-sea fan remained low, whereas deposition in the delta dwindled to 0.5–1.5 mm per year (Fig. 4i,j)9. Instead, sedimentation increased in the downstream end of the Nile Valley, where aggradation started around 7.7 ka ago20. In Middle Egypt, aggradation started before ~4.5 ka (ref. 21), earlier than the onset of aggradation near Luxor. From 4 to 3 ka, rapid floodplain aggradation in the still-confined valley setting peaked with sedimentation rates of ~12 mm per year in the Nile Valley near Luxor (Fig. 4k), while remaining low in the delta. After ~3 ka and until the present, sedimentation in the Nile Valley progressively slowed to ~2 mm per year. Further upstream beyond Aswan, no such alluvial onlap is found as base levels were controlled by the Nile cataracts. This also hampers a direct comparison of fluvial dynamics of the Egyptian Nile and the Sudanese Desert Nile16.

The decline in floodplain sedimentation in the Nile Valley near Luxor is accompanied by regional Calcisol formation (Table 1), signalling a temporary stagnation of Nilotic overbank deposition during ~3.1–2.7 ka that was previously associated with a period of lower flow during the late New Kingdom to Third Intermediate Period (Extended Data Table 5)26,29,30. Yet, our insights indicate that this cannot be fully attributed to reduced flow conditions of the Nile, as the reduced accumulation rates also reflect substantial lateral expansion of the Nile’s floodplain, which doubled in width around 2.8 ka (Fig. 3f) as pre-existing high terrace levels were re-submerged by ongoing aggradation.

Impacts on the ancient Egyptian landscape

Variations in ancient and recent Nile floods are often discussed in terms of their impacts on Egyptian society22,29,46. The Early and Middle Holocene valley entrenchment with channel-bed incision and floodplain narrowing as found in our research (~11.5–4 ka) will have resulted in lower absolute flood levels during this time, assuming no changes in peak discharge. However, this same narrower floodplain will also have made floods more turbulent with a higher amplitude, as water was funnelled through a narrower valley corridor (Fig. 3c,d). These flood dynamics would have occurred approximately between the Epipalaeolithic and the Old Kingdom/Middle Kingdom. The opposite effect will have occurred when the floodplain expanded by aggradation thereafter (~4 ka–present) (Fig. 3e–g).

The profound environmental and geomorphological changes identified herein are also likely to have impacted the utilization of the Egyptian Nile Valley landscape through time. Particularly through the Old Kingdom, perhaps into the First Intermediate Period and maybe also the Middle Kingdom (Extended Data Table 5), the floodplain contraction associated with the formation of the T3 and T4 terraces between approximately 4.54 ± 0.42 ka and 4.09 ± 0.31 ka (Fig. 3c,d) would have progressively placed the high(er) terrace levels out of reach of the annual flood. As a result, these locations would not have annually received fertile Nile silts, and effective floodwater irrigation would not have been possible at these levels. Instead, these locations may have offered opportunities in terms of settlement or temple construction, being proximal to the river, but with a low risk of flooding (Fig. 3d–f).

In contrast, large-scale floodplain aggradation together with lateral floodplain expansion (Fig. 3e,f) took place after 4.09 ± 0.31 ka, from at least the Second Intermediate Period (Extended Data Table 5). These changes will not only have greatly enlarged the area of arable land in the Nile Valley near Luxor, but will also have created and sustained lush soils by regularly depositing fertile silts at rapid rates and in large quantities. The river was also less mobile from this time onwards compared with previous periods.

These insights into the dynamics of the Egyptian Nile Valley raise the question to what extent the stepwise shrinking of the active floodplain from 4.54 ± 0.42 ka onwards, and then its expansion after 4.09 ± 0.31 ka may have contributed to the concurrent success of the ancient Egyptian agricultural economy between the Old and New Kingdom periods (Extended Data Table 5)22,28. Dating uncertainties preclude correlation with any specific events, but we would also argue strongly against the simple incorporation of any such correlations in grand causal links, especially given the fact that the environmental shifts were diachronous and may have had different expressions in different reaches of the river. Nonetheless, given the existence of major changes in floodplain reorganization, we argue for the necessary incorporation of the dynamic floodplain environment into archaeological change narratives, which must also include other endogenous and exogenous socio–political and economic factors.

Sedimentary system implications

In this study, we demonstrated that the sedimentary record of the Egyptian Nile near Luxor is a reflection of hydroclimatic changes and that storage and release of sediments from within the Nile Valley is impacted by a combination of upstream climatic and environmental factors and a downstream control exerted by sea-level change. This implies that downstream records might hold a mixed signal and could display a time delay with climatic perturbations in upstream regions. Our reconstructed fluvial evolution shows that the Nile Valley is not just a rigid conveyor belt for the transportation of water and sediments from upstream sources to downstream depocentres, but should be regarded as an important source-to-sink component itself.

Through our palaeo-environmental reconstruction near Luxor, we have shown that the single-channel Egyptian Nile of today is not analogous to the Nile system throughout much of the Holocene. For most of this time, the Egyptian Nile consisted of multiple mobile branches and did not comprise a single axial channel. Several co-existing active threads existed in a dynamic wandering-braided system from ~11.5 to 4 ka, and a number of less-dynamic straight channels were active between ~4 and 2 ka. The current single-thread, largely immobile Nile River, positioned centrally in its valley, only became established around 2,000 years ago. Importantly for archaeological prospection, our findings mean that large swaths of the buried stepped-terrace landscape remain undisturbed by fluvial erosion and thus potentially yield untouched archaeological traces of the specific age window between terrace abandonment and re-submergence by aggradation.

Hydroclimatic changes in the Nile Basin resulted in a rapidly changing fluvial system during the Holocene, with high sedimentation rates following earlier large-scale erosion, floodplain expansion following earlier contraction and a multi-channel system transforming into a single-thread system with avulsive behaviour. Such dynamics were not only the dominant drivers that shaped the Egyptian Nile Valley throughout the Holocene, but may have contributed to agro-economic dynamics in ancient Egyptian society. Ultimately, our results show that the classic view of ancient Egyptians cultivating a steadily aggrading floodplain22,28 is a great oversimplification of a much more complex fluvial system (Fig. 4h).

Methods

Sedimentary data and interpretation

Sedimentary information from 81 sediment cores retrieved by a combination of hand-operated Eijkelkamp augers and a gasoline-powered Cobra TT percussion corer was used to investigate the Nile’s Holocene fluvial deposits in its valley near Luxor, Egypt. Sediment samples were studied in ~10 cm intervals and had their characteristics such as sedimentary texture (conforming to United States Department of Agriculture standards)47, grain size, Munsell colour, degree of sorting, mica occurrence and rhizolith percentages logged on site. Boreholes reached to a mean depth of ~8 m—with many penetrating >10 m. Their spacing varied from ~20 to 200 m, depending on the heterogeneity of the subsurface. The cross section was strategically placed to span the entire valley, perpendicular to the main axis of the Nile Valley and the current river, while following governmental policies and regulatory procedures working in and around protected Egyptian Antiquities areas. Coring locations were recorded in UTM36N and the Survey of Egypt vertical datum using a Leica RTK-GNSS positioning system and subsequently stored together with the sedimentary logs for future reference (Supplementary Data 1). Subsequently, UTM36N coordinates were converted to degrees, minutes, seconds for publication purposes. Robust age information was provided through 48 quartz optically stimulated luminescence (OSL) ages, originating from 18 core sites spread across the Nile Valley (Fig. 1) strategically targeting the various sedimentary units (Fig. 2) for which OSL ages with 1σ standard deviation were calculated (Table 1; below provides further details on luminescence dating).

Luminescence dating procedures

Sampling and laboratory preparation

On the basis of the initial interpretation and reconstruction of the Holocene fluvial architecture in the Nile Valley by means of the newly constructed valley-wide cross section and after thorough inspection of the sedimentary logs, core-site locations were selected and revisited (within 1 m of their original borehole) to sample for luminescence dating; Extended Data Table 1 provides detailed sample locations and depths. Luminescence samples were collected using Eijkelkamp percussion coring equipment driven by a gasoline-powered Cobra TT hammer. For sampling, a metal core sampler (diameter 63 mm) with an exchangeable core catcher, lined with a dedicated black non-transparent PVC tube, was used to take undisturbed sediment samples of 50–100 cm in length. To prevent any possible disturbance, samples were preferentially taken from homogeneous intervals and sampling across bounding surfaces was avoided. After the sample was lifted to the surface and extruded from the sampler, the plastic liner containing the luminescence sample was cut to length (~25–30 cm), capped at both ends, labelled and wrapped in an opaque black plastic bag to avoid potential exposure to light. Sediment samples were subsequently transferred to the Geology Department of Mansoura University (Egypt) for initial sediment analyses and from there forwarded to the Oxford Luminescence Dating Laboratory at the University of Oxford (United Kingdom) for dating under a geological permit obtained by Mansoura University.

After transportation, the samples were opened and prepared under subdued orange-light conditions, with the light-exposed sample ends removed to avoid contamination. Sediment preparation followed standard laboratory procedures50, with sediments treated using hydrochloric acid and hydrogen peroxide to remove any carbonate and organic material. All samples apart from those from cores AS107 and PC38 (that is, core sites VII and XV, respectively) were sieved and separated using sodium polytungstate heavy liquid density separation to isolate sand-sized grains of quartz (Extended Data Table 1 provides sample-specific grain-size ranges). These samples were chemically etched using hydrofluoric acid to remove the alpha-irradiated outer layer of the quartz grains. Sediments were loaded into aluminium single-grain discs (100 holes per disc arranged in a 10 × 10 array, with a hole depth and diameter of 300 μm) for equivalent dose (De) measurement. Samples from cores AS107 and PC38 did not yield sufficient sand-sized grains for dating, and silt-sized grains of quartz were isolated using sieving and settling before chemical etching with fluorosilicic acid. Prepared sediment (4–11 μm) was settled onto 9.7 mm aluminium discs for De measurement.

Equivalent dose rate measurement and calculation

OSL signals from quartz were measured using Risø TL/OSL DA-15 readers fitted with 90Sr/90Y beta sources with dose rates of c. 4 Gy min−1. Ultraviolet luminescence signals were detected using a bialkali photomultiplier tube, through 7.5 mm U340 filters. Single-grain (SG) luminescence signals were stimulated with a 10 mW green (532 nm, Nd:YVO4) focused laser and multi-grain (MG) signals with a blue light-emitting diode array (470 nm, 28 mW cm−2). The single aliquot regenerative dose (SAR) protocol51,52 (Extended Data Table 2) was used for De measurement. Following pre-heat plateau and dose recovery tests, a pre-heat of 220 °C and cut-heat of 160 °C for 10 s were used, and luminescence signals were measured at 125 °C for either 1 s (SG) or 40 s (MG). Single-grain Des were calculated from the signal derived from the first 0.1 s of measurement with a background from the final 0.2 s subtracted. Multi-grain Des were calculated from signal from the first 0.5 s, minus the background from the final 10 s. To assess suitability for dating, a suite of standard rejection criteria was applied to all luminescence signals. Signals were only included in final De calculation if they satisfied the following: (1) test dose signal was at least 3σ above background levels; (2) recycling ratios and (3) OSL IR (infrared) depletion ratios53 were both within ±10% of unity (including uncertainties); and (4) recuperation was less than 5%. De determinations were made using either the central age model54 or the finite mixture model55.

Environmental dose rate determination

Environmental dose rates (Ḋ) were calculated using DRAC dose rate and age calculator56. Radionuclide concentrations were measured using inductively coupled plasma mass spectrometry and were converted into infinite-matrix Ḋs using the conversion factors of Guérin et al.57. Adjustments for attenuation by grain size and chemical etching were made using the factors of Guérin et al.57 and Bell58, respectively, and for the fine-grain quartz samples (cores AS107 and PC38), an additive a-value of 0.038 ± 0.02 (ref. 59) was used to calculate the Alpha Ḋ. To correct for attenuation by water in the sediment matrix, the factors of Aitken and ** the terrace during flood conditions and reworking its deposits. Sample AS141-1 is considered disturbed by natural forces too, as the presence of clay balls just beneath the sample and the pale-coloured sediments just above the sample indicate fluvial activity and reworking of the original terrace deposits by wadi plain run-off processes during the African Humid Period3,5. Hence, this sample was excluded from median age calculation.

Subsequently, the median age and 1σ standard deviation were calculated for each identified geogenetic unit (Table 1) by stacking the individual Gaussian distribution curves of accepted OSL dating results within each unit. This approach weighs clustering of OSL ages in assigning age ranges, leaving the age of the particular unit less sensitive to outliers64,65. Table 1 provides all calculated median age results per unit.