Officials from the Libyan Tourist Police and Antiquities Protection Agency protecting newly discovered rock art in the Jabal al-Hasawna mountains.

Officials from the Libyan Tourist Police and Antiquities Protection Agency are protecting a series of newly discovered rock engravings in the Jabal al-Hasawna mountains. The rock art was discovered by a Libyan citizen who notified the offices of the agency in Sabha, the nearest city. They are currently under investigation by experts from the Fezzan Antiquities Authority, the Archaeology Department at Sabha University, and the Brak Al-Shati Security Directorate, with a view to determining their historical significance, and how they can best be protected.

Newly discovered rock art in the Jabal al-Hasawna mountains of Libya. Libyan Tourist Police and Antiquities Protection Agency.

The new discoveries include artworks in a number of styles previously described from elsewhere in the Sahara, including art attributed to the Buffalo or Large Wild Fauna Period (so called because the art often features Giant Buffalo, Syncerus antiquus, and other extinct African megafauna). This artwork was created between 12 000 and 8000 BC by hunter gatherer populations living in a still green Sahara, and comprises geometric shapes and images of Animals such as Antelope, Aurochs, Buffalo, Fish, Giraffe, Hippopotamus, Ostrich, and Rhinoceros, painted onto wall panels with clay, manganese, iron oxide, and organic dyes. Examples of Buffalo Period rock art are found across Morocco, Algeria, and Tunisia, and are particularly abundant in the Fezzan Region of southwestern Libya, and around Oued Djerat in the northern part of the Tassili N'Ajjer, Algeria.

Also present is art from the Round Head Period, which was produced by Epipalaeolithic and Mesolithic hunter gatherers from about 7550 to about 5050 BC. Round Head art is painted onto or pecked into rock panel surfaces, and depicts Animals such as Antelope and Barbary Sheep alongside stylised Human figures with rounded heads, often engaged in dancing or other ritual activities. The best known examples of Round Head art come from the Tassili Plateau of southern Algeria, over a thousand kilometres to the southwest of the Jabal al-Hasawna, but examples are also known from the Tadrat Akakas of Libya, and the Djado Plateau of Niger. 

Art from the younger Bovidian, or Pastoral Period, has also been reported. This art style first appears around 6000 BC, and persist to about 700 BC (although most dates to between 5200 and 3800 BC), and contains the first examples of Animal-herding (pastoralism), and depicts Human figures with domestic Animals such as Cattle, Sheep, and Goats, as well as wild Animals such as Antelope, Barbary Sheep, Elephant, and Ostrich. Pastoral Period art contains the oldest known examples of domestic scenes, including women and children, in the Sahara, and is thought to have been made by Neolithic pastoralists migrating seasonally with their herds. The first Pastoral Period art was created while the Sahara was still green, while the latest was made in a desert environment. Over the period the wild Animals depicted in this art reflect this changing climate, as do the locations where it was placed, reflecting changing migration routes as the landscape dried. Examples of Pastoral Period art are common in southwestern Libya and the neighbouring Tassili n'Ajjer area of Algeria.

Younger Horse Period art has also been reported in the Jabal al-Hasawna. This style, dated to between 1200 BC and about 1000 AD, depicts people on Horses and in Chariots, and as well as the first people wearing cloths in Saharan rock art. This style is known from the Tassili n'Ajjer area of Algeria.

Camel Period art appears around 1000 BC and continues to the end of the first millennium BC. This style of art depicts the first Camels in the Sahara, but also domestic Animals such as Cattle and Goats. Men in Camel Period art are often armed with swords, spears, and shields. Examples of Camel Period art are known from Libya, Algeria, and Chad.

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More than 11 000 believed to have died in Libya flooding.

More than 11 000 people are now believed to have died in floods which hit the city of Derna on the northeast coast of Libya on Sunday 10 September 2023, with a possibility the number of dead may rise as high as 20 000. The floods occurred when high rainfall associated with Storm Daniel deposited about 400 mm of rain on the city over a 24 hour period (compared to an average of 1.5 mm for the entire month of September), which caused two dams on the Wadi Derna, a seasonal river which flows through the city and gives it its name, two collapse. The upper of these dams, which collapsed first, held about 1.5 million cubic metres of water (i.e. 1.5 million tonnes in mass). The failure of this dam deposited most of this water into the lake behind the second dam, which already held a further 22.5 million cubic metres (22.5 million tonnes) of water, causing that dam to fail as well, and sending a three metre high surge of water through the centre of the city with sufficient force to knock down multi-story buildings in its path.

The aftermath of a catastrophic flood which hit the city of Derma on the northeast coast of Libya on Sunday 10 September 2023. Jamal Alkomaty/AP.

Both of the dams which failed are believed to have been of the rockfill type, which are more prone to failure when over-topped than solid concrete dams. Rockfill dams have an impermeable, water-resilient face on their upstream side, usually made from concrete, clay, or a similar material, which retains a lake behind it, but behind this is a supporting mass of permeable rock, which supports the dam, but which can be washed away once water starts to come over the top of the dam. The dams were installed in the 1970s, during the reign of the former Libyan leader, Muammar Gadaffi, and were initially subject to regular maintenance work. However, this appears to have become erratic in nature following Gadaffi's assassination in 2011, and the civil war in Libya which followed this event. Accusations are now being made by academics and opposition politicians in Libya that this lack of maintenance was a major contributing failure to the collapse, and the government promising an enquiry and possible prosecutions.

A generalised diagram of a rockfill dam. Lau (2004).

As well as the huge number of immediate deaths caused by the flooding, the city of Derma, which before the flood had a population of about 90 000, is facing a huge ongoing humanitarian crisis, with about 30 000 people made homeless by the event and effectively no safe sources of water left in the city, due to the huge number of bodies present. Relief workers from a dozen nations have now reached the city, but the scale of the task ahead is daunting, with some agencies arguing the city should be completely evacuated as a safety measure, although with much of Libya already close to a humanitarian crisis, it is difficult to see where people would go, unless neighbouring states are willing to accept them.

An Egyptian Armed Forces rescue team clearing bodies from the streets of Derma on the northeast coast of Libya, following a disastrous flood on 10 September 2023. Ahmed Elumami/Reuters.

Most storms form due to heating of air over the sea. As the air is heated the air pressure drops and the air rises, causing new air to rush in from outside the forming storm zone. If this zone is sufficiently large, then it will be influenced by the Coriolis Effect, which loosely speaking means the winds closer to the equator will be faster than those further away, causing the storm to rotate, clockwise in the northern hemisphere and anticlockwise in the southern hemisphere.

The aftermath of a catastrophic flood which swept through the city of Derma on the northeast coast of Libya on 10 September 2023. Reuters.

Whilst the high winds associated these storms is extremely dangerous, the real danger from such storms is often the flooding. Each millibar drop in air pressure can lead to a 1 cm rise in sea level, and large storms can be accompanied by storm surges several meters high. This tends to be accompanied by high levels of rainfall, caused by water picked up by the storm while still at sea, which can lead to flooding, swollen rivers and landslides; which occur when waterlogged soils on hill slopes lose their cohesion and slump downwards, over whatever happens to be in their path.

Devastation caused by a catastrophic flood in the city of Derma on the northeast coast of Libya on 10 September 2023. Getty Images.

Such storms are common in tropical regions, but less so on the more temperate Mediterranean. However, this summer much of the eastern Mediterranean has suffered a prolonged heat wave, with temperatures regularly exceeding 40°C, and heat related deaths recorded across much of southern Europe, as well as a series of wildfires which have swept across Greece and other countries as vegetation has dried out. These events have been caused by a combination of an anticyclone (high pressure system) which formed over the Sahara then migrated northwards, intensified by an El Niño system over the southern Pacific, which tends to drive temperatures upwards in the Northern Hemisphere, both of which are considered to have been intensified by global warming.

Storm Daniel over the Mediterranean on 9 September 2023. NASA/NOAA/Wikimedia Commons.

Storm Daniel is the largest and deadliest tropical-cyclone-like storm ever recorded in the Mediterranean Region, as well as the deadliest storm globally since 2008, when Cyclone Nargis killed almost 140 000 people in Myanmar. The storm began as a low pressure system over the Ionian Sea, which then swept over the Balkan Peninsula on 4 September 2023, causing widespread flooding in Greece, Bulgaria, and Turkey, before tuning south and crossing the Mediterranean, making landfall close to Benghazi on the Libyan coast on 10 September, and then rapidly dissipating. 

Rainfall for 9-11 September 2023 on the northern coast of Libya. BBC/NASA.

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Magnitude 5.1 Earthquake off the coast of Malta.

The Seismic Monitoring and Research Group at the University of Malta recorded a Magnitude 5.1 Earthquake roughly 129 km to the south of the island, slightly before 0.20 am local time on Saturday 22 April 2023 (slightly before 10.20 pm on Friday 21 April, GMT) . No injuries have been reported but the event was felt across Malta, as well as on parts of Sicily and the Libyan coast.

The approximate location of the 22 April 2023 Malta Earthquake. USGS.

Malta is not a country generally associated with Earthquakes, but is close to an active tectonic margin, with the boundary between the African and Eurasian Plates running along the north coast of Tunisia, then along the south coast of Sicilly. This is a convergent margin, with the two continental masses being pushed together by the northward movement of Africa. This is a convergent margin, with Africa being partially subducted beneath the Eurasian Plate and fueling the volcanoes of southern and western Italy, and compression and folding of the southern part of the Eurasian Plate, causing uplift in the Apennines and Alps.

Outline map showing the approximate positions of the Eurasian (EU), Adriatic (AD) and African (AF) Plates. Di Bucci & Mazzuli (2003).

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Magnitude 4.6 Earthquake in northeastern Libya.

The Centre Seismologique Euro-Méditeranéen  recorded a Magnitude 4.6 Earthquake at a depth of 10 km about 3 km to the west of the city of Al Bayḑā on the northeast coast of Algeria, slightly before 3.20 am local time (slightly before 2.20 am GMT) on Thursday 21 February 2019. There are no reports of any damage or casualties associated with this event, though it may have been felt locally.

 The approximate location of the 11 February 2019 ’Aïn el Turk Earthquake. EMSC.

Libya lies on the northernmost part of the African Plate, while southern Europe to the north is part of Eurasia. Africa is pushing into Europe from the south, which causes Earthquakes around the Mediterranean Basin. These are most common in southeast Europe, but those in North Africa, while less frequent, are often larger and more deadly.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.

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Arsonists target Libyan oil pipeline.

A pipeline carrying oil from the Waha Oilfield in eastern Libya to the Mediterranean port of Es Sadir has been the target of an arson attack. The pipeline was set on fire at an isolation valve on the El Zkout-Es Sider pipeline, roughly 21 km from Marada on Saturday 21 April 2017, and the fire was not brought under control until Sunday 22 April. Repairs to the pipeline are expected to take several days, slowing production at the Es Sadir refinery by about 80 000 barrels (12 720 000 litres) per day.

Burning pipeline near Marada in Libya on Saturday 21 April 2018. Libyan Observer.

Libya has suffered a number of serious oil fires in recent years, caused by a combination of a decaying infrastructure, and deliberate attacks linked to political instability in the North African Country. Fighting between militia groups has occurred sporadically since the overthrow of former leader Muammar Gaddafi, as the various groups that took part in the regime change had little in common and since then have been engaged in an uneasy truce with intervals of open conflict.

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Ziwaya-Tripoli pipeline closed off due to fire.

An oil pipeline connecting the Zawiya Refinery in Libya to the capitol, Tripoli, has been closed down following an explosion and fire in the Joudaim District that broke out on Monday 26 February 2018. The pipeline supplies about two thirds of the fuel used in Tripoli, prompting fears of shortages when the news was released, but the Brega Oil Marketing Company, which operates the pipeline and supplies fuel in the city, has assured customers that it has sufficient reserves to maintain supplies until the pipeline is repaired.

Libyan firefighters tackle an oil fire near Zawiya. Libyan Observer.

Libya has suffered a number of serious oil fires in recent years, caused by a combination of a decaying infrastructure, and deliberate attacks linked to political instability in the North African Country. However on this occasion the cause of the fire appears to have been more mundane; the buried pipeline was apparently struck by a farmer while ploughing a field, resulting in a leak that ignited causing the explosion and subsequent fire. Nobody is thought to have been injured in the incident.

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Evidence for a Carboniferous glaciation in the Ennedi-Bourkou Mountains of northern Chad.

During the Late Palaeozoic the supercontinent of Gondwana covered the Southern Polar Region, with the Pole itself moving across Africa and Australia. Evidence for an extensive Southern Polar Glaciation has been found in South Australia, Oman, Ethiopia, Brazil, Egypt, Niger, and Libya. The glaciation seen in Niger and Libya seems extremely likely to continue across the northern part of Chad, which separates the the two regions, however, the remote nature and political instability of this region has prevented exploration by geologists to date.

In a paper published in the journal Geology on 29 November 2017, Daniel Le Heron of the Department of Earth Sciences at Royal Holloway, University of London, describes the results of a study of the topography of the Ennedi-Bourkou Mountains of northern Chad, made using satellite data from Google Earth, which shows the presence of an extensive Carboniferous ice-stream system.

The Ennedi-Bourkou Mountains form the southern margin of the Al Kufrah Basin, which has striated surfaces interpreted as glacial in origin around Jabal Azbah on its eastern margin, in southern Libya. However no such structures have previously been described from the less well explored Chaddian portion of the basin. Le Heron found that the Ennedi-Bourkou Mountains show a series of sinuous belts cutting across a sandstone platform dated to the Carboniferous in the early 1960s (when nobody was looking for evidence of glaciation in the Central Sahara).

Lineament analysis of Google Earth imagery, Ennedi-Bourkou region, northern Chad, illustrating suite of curvilinear features interpreted as mega-scale glacial lineations traversing outcrop belts mapped as Devonian and Carboniferous. Sinuous belts of mega-scale glacial lineations are interpreted as paleo–ice stream pathways; neighbouring regions devoid of these are interpreted as inter-stream areas. The “Mousso” structure is a possible impact crater. Le Heron (2017).

Le Heron was able to detect five main sinuous belts, each 5-12 km in width, which, combined with the interstream areas, cover an area of about 6000 km². These belts can be traced for tens of kilometres, and run approximately north to south.

High-resolution view and interpretation of a paleo–ice stream track shown in Figure 2. Note deflection of mega-scale glacial lineations (MSGLs) around hill interpreted as a nunatak. Elevation of nunatak (1100 m) and of paleo–ice stream track to the west (850 m) allows maximum thickness of ice to be estimated (i.e. less than 250 m). La Heron (2017).<250 br="" m="">

The belts are cross-cut by more recent features, such as wadis and faults, supporting the interpretation of them as ancient structures, though it is impossible to tell whether they represent a single extended glacial event or a series of glacial cycles.

Series of snapshots from Google Earth imagery of the Ennedi-Bourkou plateaux (Chad) with accompanying interpretations. (A) Interaction of mega-scale glacial lineations (yellow lines) with dipping strata of presumed pre-glacial origin (orange lines), with interpreted glacial erosion surface indicated. Scale bar applies to immediate foreground only. (B) Low-angle perspective of interpreted palaeo–ice stream pathway shown in (A). Note interpreted inter-stream area which is devoid of mega-scale glacial lineations. (C) Mega-scale glacial lineations with evidence of fault offsets (faults in red), underscoring their antiquity (d—drumlins). (D) Development of mega-scale glacial lineations on two plateau levels. La Heron (2017).

The Chadian linear structures appear to cross cut layers of rock similar to those cross-cut by similar structures in Niger, which have been used to date the Niger structures to the Visean Stage, roughly 346.7 to 330.9 million years ago. This suggests an extensive Carboniferous ice sheet in the Sahara, draining to the north. This appears to correlate with an ancient palaeo-shoreline recorded in parts of northern Chad, and dated to about 350 million years ago. The absence of any known fluvial (river-generated) systems associated with this coastline suggests a significant ice-sheet covering the land and calving at the shore margin. 

Tentative paleogeographic reconstruction of Visean ice sheet in north-central Africa, incorporating ice flow directions in Aïr Massif of northern Niger with newly documented set of paleo–ice stream pathways in northern Chad. Speculated paleo–ice stream tracks are also shown. Coastline position for Tournasian at 350 Ma. Note close association of paleo–ice stream termini and palaeo-shoreline. La Heron (2017).

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