# 11.4.2 Column-Layer Cells

Topic Version | 1 | Published | 09/11/2015 | |

For Standard | RESQML v2.0.1 |

Column-layer cells have their geometry described by nodes distributed along coordinate lines. All coordinate lines of a grid have the same number of nodes per coordinate line, although their locations may be colocated. IJK grids and unstructured column-layer grids are the two examples of column-layer grids.

Column-layer geometry supports two specific extensions for use in the description of complex reservoir structures:

- Nodes along a coordinate line may be split to provide additional nodes, which modify the geometry of the adjacent cells.

- Additional faces may be introduced to split and truncate any column-layer cell and create additional truncation cells. This extension is only available for truncated column-layer grids or for general purpose grids.