Orcadian Basin

The Orcadian Basin is a sedimentary basin of Devonian age that formed mainly as a result of extensional tectonics in northeastern Scotland after the end of the Caledonian orogeny. During part of its history, the basin was filled by a lake now known as Lake Orcadie. In that lacustrine environment, a sequence of finely bedded sedimentary rocks was deposited, containing well-preserved fish fossils, with alternating layers of mudstone and coarse siltstone to very fine sandstone. These flagstones split easily along the bedding and have been used as building material for thousands of years. The deposits of the Orcadian Basin form part of the Old Red Sandstone (ORS). The lithostratigraphic terms lower, middle and upper ORS, however, do not necessarily match exactly with sediments of lower, middle and upper Devonian age, as the base of the ORS is now known to be in the Silurian and the top in the Carboniferous.

Extent

The exact extent of the Orcadian Basin is uncertain due to later tectonic effects and burial beneath younger sediments, but it is known to have reached from the south coast of the Moray Firth to the Shetland Islands in the north and from Strathy on the Caithness coast in the west, to the Outer Moray Firth and East Shetland Platform in the east, where it is proven by hydrocarbon exploration wells. Continental sediments of the same age are also known from the Clair oilfield west of the Shetland Islands and have been tentatively identified in the West Orkney Basin. The connection of the Orcadian Basin to the Devonian basins of western Norway and eastern Greenland is not known in any detail. To the south the basin may continue almost as far south as the Highland Boundary Fault, including the half-grabens at Turriff and Rhynie.

Basin

Basin is another term for sink or bowl.

Basin may also refer to:

Geology and landforms

Basin may also refer to some types of geological depressions:

Dock (maritime)

A dock (from Dutch dok) is either the area of water between or next to a human-made structure or group of structures involved in the handling of boats or ships, usually on or close to a shore, or the structures themselves. The exact meaning varies among different variants of the English language. "Dock" may also refer to a dockyard or shipyard where the loading, unloading, building, or repairing of ships occurs.

History

The earliest known docks were those discovered in Wadi al-Jarf, an ancient Egyptian harbor dating from 2500 BCE located on the Red Sea coast. Archaeologists also discovered anchors and storage jars near the site. A dock from Lothal in India dates from 2400 BCE and was located away from the main current to avoid deposition of silt. Modern oceanographers have observed that the Harappans must have possessed great knowledge relating to tides in order to build such a dock on the ever-shifting course of the Sabarmati, as well as exemplary hydrography and maritime engineering. This was the earliest known dock found in the world, equipped to berth and service ships. It is speculated that Lothal engineers studied tidal movements, and their effects on brick-built structures, since the walls are of kiln-burnt bricks. This knowledge also enabled them to select Lothal's location in the first place, as the Gulf of Khambhat has the highest tidal amplitude and ships can be sluiced through flow tides in the river estuary. The engineers built a trapezoidal structure, with north-south arms of average 21.8 metres (71.5 ft), and east-west arms of 37 metres (121 ft).

Basin (chanson de geste)

Basin is a chanson de geste about Charlemagne's childhood. While the Old French epic poem has been lost, the story has come down to us via a 13th-century Norse prose version in the Karlamagnús saga.

Plot

At the death of his father, an angel warns the young Charlemagne to take to the Ardennes and join up with the notorious thief Basin. During their adventures, Charlemagne learns of a plot to kill him and, in the end, the traitors are discovered, Charlemagne is crowned and Basin the thief is rewarded.

Historical sources

The traitors in the story (Rainfroi and Helpri) are most likely based on Chilperic and Ragenfrid who were defeated by Charles Martel in 717 CE. It is unknown if the author was acquainted with an 11th-century version of these events called Passio Agilolfi.

Influence

The names of the traitors in Basin were passed on to two other chansons de geste about Charlemagne's youth: Mainet and Berthe aus grans piés.

References