In terms of time scale in geology, Quaternary is the present-day time and it began 2.6 million years ago. A lot of this time period relates to the Ice Age. Quaternary sediments are the soft material that has been deposited during this time. In Ireland much of this is related to the movement of glaciers and ice sheets. The main types of sediments shown on the map are tills (boulder clays), gravels, sands and peat. Over most parts of Ireland, these sediments cover the bedrock (solid rock at or below the land surface). Geologists map and record information from the shallow sediments which can be seen at or near the surface. This information along with boreholes (a deep narrow round hole drilled in the ground), geophysical data (information on the physical properties of the Earth's surface and subsurface e.g. magnetics, gravity and electromagnetics) and geochemical data (chemical properties) is used to create the map. Areas are drawn on a map to show where sediments are found. We collect new data to update our map and use data made available from other sources. This map is to the scale 1:50,000 (1cm on the map relates to a distance of 500m). It is a vector dataset. Vector data portray the world using points, lines, and polygons (areas). The sediments data is shown as polygons. Each polygon holds information on the sediment type, sediment code and its unique identifier.