IOGP Report 373-03 – Coordinate and area descriptions for contract and unitisation definitions


IOGP Report 373-03

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Geomatics Guidance Note 3: Coordinate and area descriptions for contract and unitisation definitions

Contract Areas, Licence Block Boundaries, and Reserves Unitisation Agreements often have been inadequately described by licensing authorities and regulators, licence operators, and between partners (for unitisation agreements). This can result in overlapping of, and/or unlicensed slivers between adjacent licences. This has caused uncertainty between operators and between licencing authorities and operators at both the acquisition and the development phases of projects. This document sets out guidance for describing boundaries which, if followed for new contract areas, will help alleviate many of the existing issues.

This Guidance Note is intended to be useful to four general groups:

1) Licensing authorities
2) Exploration managers and lawyers in hydrocarbon exploration companies who negotiate for
licence acreage but who may have limited geodetic awareness
3) Geomatics professionals in hydrocarbon exploration and development companies, for whom
the guidelines may serve as a useful summary of accepted best practice
4) Partners, Geoscientists and other entities engaged in unitisation agreements

The guidance note is intended to apply to both onshore and offshore areas, however it does not attempt to cover every aspect of licence boundary definitions or unitisation agreements.

This is the sixth version of this guidance note, released in June 2020. This guidance note was first released in 1995 and last updated in 2014.

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