A guide to a new Geographical Information System for the Chalk of the Thames Basin : the Thames Chalk Information System (TCIS)

摘要

BGS work on the Chalk Group of the Thames Basin has amassed large quantities of geologicaludinformation about thickness, facies, marker-beds, biostratigraphy and structure, only a small partudof which is incorporated into the geological map. More recently there has been wider use andudinterpretation of borehole data to underpin the development of 3D geological models. There is audpressing need to organise these disparate data in a way that can easily be compared andudinterrogated, as well as to capture the results of relevant published research outside BGS. Thisudproject addresses this need by creating a new spatial database, the Thames Chalk InformationudSystem (TCIS). The database uses ArcGIS technology to display key information layers aboutudthe Chalk. As well as standard topographical and geological information, TCIS includes layersuddescribing: Group, Subgroup, and formational thickness; structural data; detailed stratigraphicaluddata; coverage of 3D geological models that include units or surfaces of the Chalk Group;udregions where data coverage limits our understanding of the Chalk. Hydrogeological data isudcurrently being compiled as part of a related project; it is not currently available forudincorporation into the TCIS, but will eventually be added. Basic information about the contentudand methodology used to compile the data in the TCIS is outlined in the main body of this report.udHydrogeological data was delivered through a separate project, and its features are the subject ofuda separate report. The aim of this report is to provide sufficient background information to allowudmeaningful use of the TCIS database; there is no new data interpretation.