The Single Onshore Borehole Index (SOBI) is an index of over 1 million boreholes, shafts and wells and references collections of digital and analogue records from all forms of drilling and site investigation work held by the BGS. The index covers onshore and near shore boreholes from Great Britain dating back to at least 1790 and ranging from one to several thousand metres deep. Some 50,000 new boreholes are added each year. The majority of the records contain written descriptions of the ground encountered. The SOBI index database originated in 1988 from a number of existing tables and from data input from a variety of coding forms. Therefore not all fields in the database are populated and data that should be in some fields may currently form part of the entries in another. The index is available on the BGS website via the Geoindex
