Gulf of Gabès
Encyclopedia
Headlands and bays
Headlands and bays are two related features of the coastal environment.- Geology and geography :Headlands and bays are often found on the same coastline. A bay is surrounded by land on three sides, whereas a headland is surrounded by water on three sides. Headlands are characterized by high,...
on Tunisia
Tunisia
Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...
's east coast
Coast
A coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...
in the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
, off North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
. The gulf roughly spans the coast from modern day the town of Mahrès
Mahrès
Mahrès is a town and commune in the Sfax Governorate, Tunisia. As of 2004 it had a population of 14,499.-References:...
in Sfax Gouvernorate
Sfax
Sfax is a city in Tunisia, located southeast of Tunis. The city, founded in AD 849 on the ruins of Taparura and Thaenae, is the capital of the Sfax Governorate , and a Mediterranean port. Sfax has population of 340,000...
to Djerba
Djerba
Djerba , also transliterated as Jerba or Jarbah, is, at 514 km², the largest island of North Africa, located in the Gulf of Gabes, off the coast of Tunisia.-Description:...
. At the head of the gulf is the city of Gabès (Ghannouche)
Gabès
Gabès , also spelt Cabès, Cabes, Kabes, Gabbs and Gaps, the ancient Tacape, is the capital city of the Gabès Governorate, a province of Tunisia. It lies on the coast of the Gulf of Gabès. With a population of 116,323 it is the 6th largest Tunisian city.-History:Strabo refers to Tacape as an...
where the tide
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the moon and the sun and the rotation of the Earth....
s have a large range of up to 2.1 meters at spring tides. Both Gabès and Sfax are major port
Port
A port is a location on a coast or shore containing one or more harbors where ships can dock and transfer people or cargo to or from land....
s on the gulf, supporting sponge
Sea sponge
Sponges are animals of the phylum Porifera . Their bodies consist of jelly-like mesohyl sandwiched between two thin layers of cells. While all animals have unspecialized cells that can transform into specialized cells, sponges are unique in having some specialized cells, but can also have...
and tuna
Tuna
Tuna is a salt water fish from the family Scombridae, mostly in the genus Thunnus. Tuna are fast swimmers, and some species are capable of speeds of . Unlike most fish, which have white flesh, the muscle tissue of tuna ranges from pink to dark red. The red coloration derives from myoglobin, an...
fisheries, with Gabès being the economic and administrative center.
Antiquity
The Latin name Syrtis Minor is used by Pliny the ElderPliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
, quoting an earlier description in Polybius
Polybius
Polybius , Greek ) was a Greek historian of the Hellenistic Period noted for his work, The Histories, which covered the period of 220–146 BC in detail. The work describes in part the rise of the Roman Republic and its gradual domination over Greece...
1.39.2, who uses the equivalent (elsewhere also ).
An alternative name was Lotophagitis surtis "Syrtis of the lotus-eaters
Lotus-eaters
In Greek mythology, the lotus-eaters , also referred to as the lotophagi or lotophaguses or lotophages , were a race of people living on an island near North Africa dominated by lotus plants...
, reported by Strabo
Strabo
Strabo, also written Strabon was a Greek historian, geographer and philosopher.-Life:Strabo was born to an affluent family from Amaseia in Pontus , a city which he said was situated the approximate equivalent of 75 km from the Black Sea...
. (Compare Syrtis Major
Syrtis Major
Syrtis Major Planum is a "dark spot" located in the boundary between the northern lowlands and southern highlands of Mars. It was discovered, on the basis of data from Mars Global Surveyor, to be a low-relief shield volcano, but was formerly believed to be a plain, and was then known as Syrtis...
, the ancient name of the Gulf of Sidra.)
Syrtis is referred to in the New Testament of the Bible where the Apostle Paul relates being sent in chains to Rome to stand trial before Caesar Nero. The crew of his ship was worried about being driven by a storm into Syrtis, and took precautions to prevent it, resulting, eventually, in being shipwrecked on the island of Malta in the Mediterranean Sea.
Strabo
Strabo
Strabo, also written Strabon was a Greek historian, geographer and philosopher.-Life:Strabo was born to an affluent family from Amaseia in Pontus , a city which he said was situated the approximate equivalent of 75 km from the Black Sea...
refers to Tacape (the modern Gabès
Gabès
Gabès , also spelt Cabès, Cabes, Kabes, Gabbs and Gaps, the ancient Tacape, is the capital city of the Gabès Governorate, a province of Tunisia. It lies on the coast of the Gulf of Gabès. With a population of 116,323 it is the 6th largest Tunisian city.-History:Strabo refers to Tacape as an...
) as an important entrepot of the Lesser Syrtis.
Geography
Most sources consider the Gulf of Gabès as just being within the line between the northwest tip of Djerba (Jerba) IslandDjerba
Djerba , also transliterated as Jerba or Jarbah, is, at 514 km², the largest island of North Africa, located in the Gulf of Gabes, off the coast of Tunisia.-Description:...
on the southeast and Ras Yonga (Point Yonga) on the northwest. Ras Yonga is just north of the island of Jazīrat Khunayyis and its marshes and some 52 kilometres (32 mi) southwest of Sfax. The geographer Strabo
Strabo
Strabo, also written Strabon was a Greek historian, geographer and philosopher.-Life:Strabo was born to an affluent family from Amaseia in Pontus , a city which he said was situated the approximate equivalent of 75 km from the Black Sea...
indicated that the entrance to the gulf was located at the islands of Cercinna (Kerkennah)
Kerkennah Islands
Kerkennah Islands are a group of islands lying off the east coast of Tunisia in the Gulf of Gabes, at . The Islands are low-lying being no more than 13 metres above sea level. The main islands are Chergui and Gharbi. The archipelago has an area of 160 km2 and a population of 14,400...
and Meninx (Djerba). Following Strabo gives a larger area with the line being from just north of Sfax to Djerba Island. That larger area would include part of the Kerkennah Islands
Kerkennah Islands
Kerkennah Islands are a group of islands lying off the east coast of Tunisia in the Gulf of Gabes, at . The Islands are low-lying being no more than 13 metres above sea level. The main islands are Chergui and Gharbi. The archipelago has an area of 160 km2 and a population of 14,400...
and the coast around Sfax. The centroid for the smaller gulf is at 33°59′29"N 10°24′09"E, and the distance across is 68.5 kilometres (42.6 mi), with a depth of 51 kilometres (31.7 mi). The larger gulf is 150 kilometres (93 mi) across with a depth of 90 kilometres (56 mi), and the centroid is at 34°04′48"N 10°28′36"E.
The entire Gulf of Gabès, both larger and smaller versions, is underlain by the continental shelf of the African Plate
African Plate
The African Plate is a tectonic plate which includes the continent of Africa, as well as oceanic crust which lies between the continent and various surrounding ocean ridges.-Boundaries:...
, and is nowhere deeper than 200 meters. During the Permian Period
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
and Triassic Period
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
, carbonate minerals
Carbonate minerals
Carbonate minerals are those minerals containing the carbonate ion: CO32-.-Anhydrous carbonates:*Calcite group: Trigonal**Calcite CaCO3**Gaspeite CO3**Magnesite MgCO3**Otavite CdCO3**Rhodochrosite MnCO3**Siderite FeCO3**Smithsonite ZnCO3...
and evaporite
Evaporite
Evaporite is a name for a water-soluble mineral sediment that result from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporate deposits, marine which can also be described as ocean deposits, and non-marine which are found in standing bodies of...
s were deposited in the Gulf of Gabes which now form salt dome
Salt dome
A salt dome is a type of structural dome formed when a thick bed of evaporite minerals found at depth intrudes vertically into surrounding rock strata, forming a diapir....
s and diapir
Diapir
A diapir is a type of intrusion in which a more mobile and ductily-deformable material is forced into brittle overlying rocks. Depending on the tectonic environment, diapirs can range from idealized mushroom-shaped Rayleigh-Taylor instability-type structures in regions with low tectonic stress...
s. In addition carbon and hydrocarbons primarily from vegetation were deposited. These now form the basis for the oil and gas industry in the gulf. Among the important oil and gas fields in the gulf are the Ashtart Field and the Chergui Field. The Ashtart Oil Terminal lies just outside the gulf at 34°17′N 11°23′E where tankers can easily tranship the oil.
External links
- Port Gabes, photograph from Panoramio