Boreholes chiefly penetrating the shallow subsurface, enabling detailed characterisation of layers to a maximum depth of about 500 metres.

Data from the British Geological Survey's GeoIndex Collections theme are made available for viewing here. GeoIndex is a website that allows users to search for information about BGS data collections covering the UK and other areas world wide. Access is free, the interface is easy to use, and it has been developed to enable users to check coverage of different types of data and find out some background information about the data. More detailed information can be obtained by further enquiry via the web site: www.bgs.ac.uk/geoindex.

This layer of the map based index (GeoIndex) shows the location of hydrocarbon wells known to BGS. Exploration for hydrocarbons by drilling began in the 19th century and locations were recorded in latitude/longitude until about 1960. These locations have been converted to national grid. The majority of the wells have formed part of basin studies by BGS and are therefore reliably located. There may be some discrepancies in location data between various databases, originating from project modifications and which original source was preferred.

This layer of the Map based index (GeoIndex) shows the location of records of boreholes, shafts and wells from all forms of drilling and site investigation work. Some 850,000 records dating back over 200 years and ranging from one to several thousand metres deep. Currently some 50,000 new records are being added to the collection each year. The dataset available via the GeoIndex is a snapshot, taken at a particular date, of the Single Onshore Borehole Index. Although the GeoIndex is updated at regular intervals more information may be available than is shown.

The map shows the location and names of boreholes with digital geophysical logs acquired by the former National Coal Board and British Coal during their exploration for coal in the UK. Ownership of UK coal exploration data was transferred to the Coal Authority (Coal Authority) following privatisation of the UK coal industry. The Coal Authority have appointed the British Geological Survey as custodian of this important national geological data archive. These data are in general publicly available; however, access to data within active mining licences is restricted in that it requires the consent of the mining licensee. The Coal Authority data archive includes digital data for some of the geophysical borehole logging. These are mainly in the form of original field tapes; however, also available are some data transcribed onto more modern media during BGS projects. The BGS will be pleased to provide information on data availability for named boreholes or within specified geographic areas, together with cost estimates and options for supplying copies.

This layer of the map based index (GeoIndex) shows the location of drillcore, bulk specimens, unwashed cuttings and processed material from onshore boreholes drilled in UK by BGS, commercial and public bodies. The majority of borehole cores and samples are available for study and sub-sampling by bona fide academics and commercial companies. Commercial companies are charged for access; academics will need to complete an academic waiver form.

This layer of the map based index (GeoIndex) shows the location of site reports covering a wide range of drilling and site investigation work. Some 2000 reports include the logs from over 10 000 boreholes in addition to those held in the borehole index. The rectangles shown are drawn using the SW and NE corners of the site maps.

This layer of the map based index (GeoIndex) shows the location of onshore UK boreholes known to BGS that have digital or paper geophysical borehole logs. The details given for each borehole are, the name of the borehole, the grid reference and the format, ie. paper or digital. Scattered distribution of boreholes, locally dense coverage, few logs from Scotland. The GeoIndex is updated at regular intervals but more information may be available than is shown at any one time.

This layer of the Map based index (GeoIndex) shows the location of registered samples of drillcore and washed cuttings from onshore boreholes drilled in UK by BGS, commercial and public bodies, representing almost 10,000 boreholes. There is also a drillcore collection taken from onshore boreholes drilled in England and Wales by the BGS and commercial and public bodies.

The map based index includes outlines for some 8,000 opencast coal prospecting sites dating from the 1940s until the mid 1990s. The index leads to information on the records of some 1 million boreholes (additional to those shown in the Borehole Records layer) drilled during site exploration and also the accompanying plans and other data, all filed in 3,618 boxes. The sites include those that have been drilled and not worked and also those that have been exploited. The original data, hardcopy maps, were received from the Coal Authority in 2001.