Mineral Resource Polygons Northern Ireland (Internal Geological Boundaries Retained)

Mineral resource were defined within the GIS, using digital geological line work at 1:50 000 scale (the BGS\GSNI DiGMapNI 1: 50k dataset for Northern Ireland from 01.08.2011). For areas with no available 1:50 000 scale geological mapping, 1:250 000 scale data was used (areas of Tyrone, Down and Armagh). Data processing steps: [1] A list and map of the geological lithologies for each of the six counties were supplied to the Economic Geologist for interpretation of which bedrock and superficial geological formations might now, or in the foreseeable future, be of economic value. As many sources of information as possible were consulted when considering which geological units constitute a mineral resource, ranging from historical publications to consultation with geologists with specialist knowledge of the local area. The majority of decisions were based on existing publications such as memoirs, the ‘BritPits’ mines and quarries database and advice from both BGs and GSNI geologists with area-specific knowledge. After all relevant sources of information had been consulted, the lithologies identified in the DiGMap dataset were assigned to the relevant mineral resource classification, for example the Armagh limestone (ARMA-LMST) = Limestone Carboniferous resource. Once the lithologies from DiGMAp were attributed with resource information and separated out into resource data layers. Geological lines such as faults removed and the final dataset created. All internal lines between different lithologies e.g. Armagh limestone (ARMA-LMST) and Dartry limestone (DARL-LMST) are retained and an attribute added to indicate that they fall into the carboniferous limestone categories. [2] Interpretations are then extracted from the derived from DiGMapNI-50 and DigMapNI-250 versions available at 01.08.2011 and given a mineral resource attribute and colour. Editing was carried out to resolve the mismatching sheet boundaries and gaps in the data. [3] The data was re-supplied to the Economic Geologist for correction. Small areas of resources were deleted when considered to be uneconomic/unworkable. [4] Dataset preparation and cleaning was carried out by GIS specialist. [5] Data produced was merged together to produce national dataset based on resource commodity. [6] Mineral commodity and name attributes are correctly assigned using the legend supplied by Economic Geologist. [7] Polygons dissolved based on name attribute, removing all county boundaries. [8] Remove sliver polygons (created as a result of geological sheet boundaries) where possible and re-dissolve. [9] Multipart to single part operation conducted on each dataset. [10] Redundant attributes removed. [11] Repair geometry operation to clean the dataset. [12] Economic Geologist approves final resource dataset.

INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology

Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services