The River Ock is a small English

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 which is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the River Thames

River Thames

The River Thames flows through southern England. It is the longest river entirely in England and the second longest in the United Kingdom. While it is best known because its lower reaches flow through central London, the river flows alongside several other towns and cities, including Oxford,...

. It has as its catchment area

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 the Vale of White Horse

Vale of White Horse

The Vale of White Horse is a local government district of Oxfordshire in England. The main town is Abingdon, other places include Faringdon and Wantage. There are 68 parishes within the district...

, a low-lying and wide valley in South Oxfordshire

Oxfordshire

Oxfordshire is a county in the South East region of England, bordering on Warwickshire and Northamptonshire , Buckinghamshire , Berkshire , Wiltshire and Gloucestershire ....

 and flows into the River Thames, at Abingdon

Abingdon, Oxfordshire

Abingdon or archaically Abingdon-on-Thames is a market town and civil parish in Oxfordshire, England. It is the seat of the Vale of White Horse district. Previously the county town of Berkshire, Abingdon is one of several places that claim to be Britain's oldest continuously occupied town, with...

 on the reach above Culham Lock

Culham Lock

Culham Lock is a lock on the River Thames in England close to Culham, Oxfordshire. It is on a lock cut to the north of the main stream, which approaches the large village of Sutton Courtenay...

.

Course

The River Ock rises near the village of Little Coxwell

Little Coxwell

Little Coxwell is a small village and civil parish in about south of Faringdon and east of Great Coxwell. Little Coxwell was part of Berkshire until the 1974 local government boundary changes transferred the Vale of White Horse to Oxfordshire....

. It collects tributaries from each village along the base of the White Horse Hills, where springs emanating from the chalk

Chalk

Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....

 hills allowed settlements to flourish in former times.

From Little Coxwell, the Ock runs around Longcot

Longcot

Longcot is a village and civil parish in the Vale of White Horse District. It was part of Berkshire until the 1974 boundary changes transferred it to Oxfordshire. The village is about south of Faringdon and about northeast of Shrivenham. The A420 road between Swindon and Oxford passes through the...

 and flows past Stanford in the Vale

Stanford in the Vale

Stanford in the Vale is a large village and civil parish about south-east of Faringdon and north-west of Wantage in the Vale of White Horse. It was part of Berkshire until the 1974 boundary changes transferred the Vale of White Horse to Oxfordshire....

, where it is about 10 feet (3 m) wide. The name of Stanford comes from Stony Ford, possibly alluding to the Ock crossing at Stanford Mill. Thence it runs past Charney Bassett

Charney Bassett

Charney Bassett is a village and civil parish about north of Wantage and east of Faringdon in the Vale of White Horse. It was part of Berkshire until the 1974 boundary changes transferred it to Oxfordshire.-Archaeology:...

, Lyford

Lyford, Oxfordshire

Lyford is a village and civil parish about north of Wantage. Historically it was part of the ecclesiastical parish of Hanney. Lyford was part of Berkshire until the 1974 boundary changes transferred the Vale of White Horse to Oxfordshire.-Manors:...

, Garford

Garford

Garford is a village and civil parish about west of Abingdon. It was part of Berkshire until the 1974 boundary changes transferred it to Oxfordshire...

 and Marcham

Marcham

Marcham is a village and civil parish about west of Abingdon, Oxfordshire. It was part of Berkshire until the 1974 boundary changes transferred it to Oxfordshire.-Archaeology:...

 Mill, before losing its identity and its waters to the Thames at Abingdon by the old Hygienic Laundry building. An iron bridge crosses at the junction which was built by the Wilts & Berks Canal Company. This gives the erroneous impression that the Ock is that canal, but in fact the original canal entrance a few yards downstream is now blocked up. This has been replaced under a restoration project by a newer entrance closer to Culham Lock

Culham Lock

Culham Lock is a lock on the River Thames in England close to Culham, Oxfordshire. It is on a lock cut to the north of the main stream, which approaches the large village of Sutton Courtenay...

.

The soils through which the River Ock flows are the Jurassic

Jurassic

The Jurassic is a geologic period and system that extends from about Mya to  Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...

 sedimentary series (Greensand

Greensand

Greensand or Green sand is either a sand or sandstone, which has a greenish color. This term is specifically applied to shallow marine sediment, that contains noticeable quantities of rounded greenish grains. These grains are called glauconies and consist of a mixture of mixed-layer clay...

s, Gault, Kimmeridge Clay

Kimmeridge Clay

The Kimmeridge Clay Formation is a sedimentary deposit of fossiliferous marine clay which is of Jurassic age. It occurs in Europe.Kimmeridge Clay is arguably the most economically important unit of rocks in the whole of Europe, being the major source rock for oil fields in the North Sea hydrocarbon...

 and corallian limestone

Corallian Limestone

Corallian Limestone is a coralliferous sedimentary rock, laid down in Jurassic times. It is a hard variety of "coral rag". Building stones from this geological structure tend to be irregular in shape. It is often found close to seams of Portland Limestone...

), while some of its tributaries arise in chalk

Chalk

Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....

 springs. Until recent times, native crayfish

Austropotamobius pallipes

Austropotamobius pallipes is an endangered European freshwater crayfish, and the only species of crayfish native to the British Isles. Its common names include white-clawed crayfish and Atlantic stream crayfish.-Distribution and ecology:...

 and many freshwater

Freshwater

Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 species inhabited the river. Increased housing in the Vale, with the resultant surface drainage, may have threatened these species but surveys have not yet been performed in the 21st Century.

Although normally placid, the Ock can flood low-lying areas of south Abingdon after persistent heavy rainfall; this last occurred in July 2007

2007 United Kingdom floods

The 2007 United Kingdom floods were a series of destructive floods that occurred in various areas across the country during the summer of 2007. The most severe floods occurred across Northern Ireland on 12 June; East Yorkshire and The Midlands on 15 June; Yorkshire, The Midlands, Gloucestershire,...

.