SURCON Professional key terms

A systematic public record of land parcels in an area, showing their location, boundaries, area and tenure or ownership, kept current for taxation, planning and land administration.

The surveying work that defines, marks and records parcel boundaries and areas so that they can be entered into a cadastre and used to support land titles.

The official process of recording rights and interests in land in a public register, giving legal certainty and usually priority to the registered holder against later claims.

A written legal document that evidences ownership of a parcel of land and is used to transfer or prove the owner's interest in the property.

In Nigerian land administration, a statutory document issued by a state government granting a right of occupancy over land for a stated purpose and term.

A statutory or customary entitlement to use and occupy land in Nigeria, which may be granted formally or acquired through customary tenure and later documented.

A durable physical mark, such as a concrete pillar or metal pin, placed on the ground to identify and preserve a survey point or parcel corner for future reference.

A defined area of land with identifiable boundaries and a unique identifier, treated as a single unit for ownership, valuation, taxation or land management.

A legal right allowing one person to use another person's land for a specific purpose, such as access or utility passage, without owning that land.

A scaled drawing and supporting data prepared by a surveyor that shows parcel boundaries, measurements and beacons needed for registration or development approval.

The equipotential surface of the Earth's gravity field that would coincide with mean sea level and serves as the reference surface for orthometric heights.

A mathematically defined smooth surface approximating the Earth's shape, used as the basis for horizontal coordinates and geodetic computations within a datum.

A defined reference framework comprising an ellipsoid and its position and orientation relative to the Earth, to which coordinates and heights are tied.

A set of precisely coordinated survey points established across an area, used as fixed references for extending surveys, checking accuracy and linking local work to the national framework.

The World Geodetic System 1984, a global geocentric datum and ellipsoid widely used for GNSS positioning and for expressing latitude, longitude and ellipsoidal height.

The height of a point above the geoid, commonly called height above mean sea level, used in engineering, mapping and flood studies.

The height of a point above the reference ellipsoid, obtained directly from GNSS and differing from orthometric height by the geoid undulation.

The separation between the geoid and the reference ellipsoid at a given place, used to convert ellipsoidal height to orthometric height.

Global Navigation Satellite System, a family of satellite positioning systems such as GPS, GLONASS, Galileo and BeiDou that provide position and time worldwide.

Real-Time Kinematic positioning, a GNSS technique that uses carrier-phase measurements and a nearby base station or network to deliver centimetre-level coordinates immediately in the field.

The science of obtaining measurements and three-dimensional information about objects and terrain from photographs or other imagery, often taken from aircraft or drones.

Photography of the ground taken from an aircraft or drone, usually with overlapping frames so that terrain and features can be mapped in three dimensions.

Two overlapping images of the same area taken from different viewpoints, which together allow depth perception and three-dimensional measurement of features.

An aerial or satellite image that has been geometrically corrected so that it has a uniform scale and can be used as a map, with displacement removed.

A point on the ground whose coordinates are known accurately and which appears clearly in imagery, used to georeference and check the accuracy of photogrammetric products.

A digital representation of terrain height at regularly spaced points or cells, used for analysis, contour generation and three-dimensional modelling.

Light Detection and Ranging, a remote sensing method that uses laser pulses to measure distances and produce dense, accurate three-dimensional point clouds of terrain and objects.

The acquisition of information about the Earth's surface from a distance using sensors on satellites, aircraft or drones, without direct physical contact with the target.

Geographic Information System, a computer system for capturing, storing, analysing and displaying spatially referenced data together with its attributes to support decision-making.

A GIS data model that represents geographic features as points, lines and polygons with associated attributes, suitable for discrete objects such as parcels and roads.

A GIS data model that represents geographic information as a grid of cells, each holding a value, commonly used for imagery, elevation and continuous surfaces.

The set of rules describing how spatial features relate to one another, such as adjacency and connectivity, used to maintain consistency and support network and overlay analysis.

The process of assigning real-world coordinates to a map, image or dataset so that it aligns correctly with other spatial data in a known reference system.

A defined system of coordinates, datum and projection that specifies how positions on the Earth are expressed as numbers, ensuring spatial data from different sources align.

The ratio between a distance on a map and the corresponding distance on the ground, controlling the level of detail and extent that can be shown.

Failure by a surveyor to exercise the reasonable skill and care expected of the profession, resulting in loss or damage to a client or third party.

A formal set of principles and rules governing the conduct of surveyors, covering integrity, competence, confidentiality and the public interest.

A situation where a surveyor's personal, financial or other interests could improperly influence professional judgement or duty to a client or the public.

The care and investigation a surveyor or client should reasonably carry out before acting, such as checking title, records and site conditions to avoid errors or disputes.

A person who has met the education, experience and examination requirements and is officially registered and permitted to carry out survey work and certify plans.