bedrock_drillings
The centralised data storage facilities of the Geological Survey of Finland (GTK) contain altogether 28857 deep drill holes and boreholes to the bedrock. The drillings began in the 1920's and they still continue. The drilling data has been collected to databases since in 1989. The information of drillings which are older than this has been digitised when necessary.
The deep drill holes of the bedrock are a spatial data in which the rock sample has been taken from a certain location by drilling. The data contains the information which is related to this sample site and to the core sample. The azimuth, dip and length of the drill hole vary according to the geological environment of the area. The drilling is performed based on the drilling plan drawn up by a geologist. The geologist supervises the drilling site and the realization of the plan and observes and records the information to the database.
The following information is saved to the database: the information related to the positioning and location of the drilling, the information about the drilling organization, the information of the storage place of the core sample, the dip of the drill hole, the lithological information of the sample, cutting angle of the structures, the ore minerals and their appearance in the sample, mineral alteration, structure and texture, stratigraphy, core loss, analysed sample intervals and the geochemical analysis results, physical and petrophysical laboratory measurements, drill hole soundings and thin sections.
In the deep drill holes the azimuth is determinated in degrees. In the full circle there are 360°. The cardinal azimuth is set to be North (000° or 360°). The hole azimuth is decided by the geologist assisted by geophysical background information and geophysicist. The objective is to get a representative sample of the bedrock units.
Hole dip refers to the angle between a horizontal direction and a drilling. The hole dip in the databases of GTK is represented in degrees (°). The dip of the vertical hole is 90°. In horizontal hole the dip is 0°. In that case the drilling has been performed either in a mine or in a quarry or the sample is continuous gouge sample sawed from the bedrock. With respect to the horizontal surface the dip of the drill hole is negative upwards. For example, when a dip is -45° the hole has been drilled in underground mine in the angle of 45 degrees to upwards. The dip of the hole to be drilled is decided by the geologist assisted by geophysical background information and geophysicist. The dip can be presented also as grads. This unit has been used mainly by mining companies.
The length of the drilled hole in the databases of the GTK is represented in metres (m). In addition to the drilling plan, the capacity of the drilling machine and the quality of the bedrock affect the length of the drill hole. In the shattered bedrock the hole can be jammed before the objective length. The lengths of the drilled holes vary from 1 metre to 2,5 kilometres.
Petrophysical laboratory measurements have been made from the drill core since about the year 1965. Since the year 1963 petrological and ore analyses have been made from the selected core samples. The use of analyses was established and increased at the end of the 1980's with the development of analysis methods. During the present the geochemical analyses are an essential part of the drilling project and are done from all the bore holes, with few exceptions. The type samples representing the lithological units of the area and the sample intervals significant to exploration are selected for analyses.
The deep drill holes have been made by the following programmes of the GTK: ore exploration, rock and mineral aggregate studies, natural stone investigations, bedrock mapping and urban mapping. In addition to these, the deep drill holes have been made among others by Outokumpu, Rautaruukki and Lapin Malmi and by the cooperation projects drawn by the universities. The data sets from different sources are not commensurable and information on the quality of the data is partly lacking. The data have been digitised when necessary and a part of the drilling information is still in the paper based archives.
The deep drill holes of the bedrock are a spatial data in which the rock sample has been taken from a certain location by drilling. The data contains the information which is related to this sample site and to the core sample. The azimuth, dip and length of the drill hole vary according to the geological environment of the area. The drilling is performed based on the drilling plan drawn up by a geologist. The geologist supervises the drilling site and the realization of the plan and observes and records the information to the database.
The following information is saved to the database: the information related to the positioning and location of the drilling, the information about the drilling organization, the information of the storage place of the core sample, the dip of the drill hole, the lithological information of the sample, cutting angle of the structures, the ore minerals and their appearance in the sample, mineral alteration, structure and texture, stratigraphy, core loss, analysed sample intervals and the geochemical analysis results, physical and petrophysical laboratory measurements, drill hole soundings and thin sections.
In the deep drill holes the azimuth is determinated in degrees. In the full circle there are 360°. The cardinal azimuth is set to be North (000° or 360°). The hole azimuth is decided by the geologist assisted by geophysical background information and geophysicist. The objective is to get a representative sample of the bedrock units.
Hole dip refers to the angle between a horizontal direction and a drilling. The hole dip in the databases of GTK is represented in degrees (°). The dip of the vertical hole is 90°. In horizontal hole the dip is 0°. In that case the drilling has been performed either in a mine or in a quarry or the sample is continuous gouge sample sawed from the bedrock. With respect to the horizontal surface the dip of the drill hole is negative upwards. For example, when a dip is -45° the hole has been drilled in underground mine in the angle of 45 degrees to upwards. The dip of the hole to be drilled is decided by the geologist assisted by geophysical background information and geophysicist. The dip can be presented also as grads. This unit has been used mainly by mining companies.
The length of the drilled hole in the databases of the GTK is represented in metres (m). In addition to the drilling plan, the capacity of the drilling machine and the quality of the bedrock affect the length of the drill hole. In the shattered bedrock the hole can be jammed before the objective length. The lengths of the drilled holes vary from 1 metre to 2,5 kilometres.
Petrophysical laboratory measurements have been made from the drill core since about the year 1965. Since the year 1963 petrological and ore analyses have been made from the selected core samples. The use of analyses was established and increased at the end of the 1980's with the development of analysis methods. During the present the geochemical analyses are an essential part of the drilling project and are done from all the bore holes, with few exceptions. The type samples representing the lithological units of the area and the sample intervals significant to exploration are selected for analyses.
The deep drill holes have been made by the following programmes of the GTK: ore exploration, rock and mineral aggregate studies, natural stone investigations, bedrock mapping and urban mapping. In addition to these, the deep drill holes have been made among others by Outokumpu, Rautaruukki and Lapin Malmi and by the cooperation projects drawn by the universities. The data sets from different sources are not commensurable and information on the quality of the data is partly lacking. The data have been digitised when necessary and a part of the drilling information is still in the paper based archives.
dataset
:
1
English
Geoscientific information
GEMET - INSPIRE themes, version 1.0:
19.074431,
59.738815,
32.971119,
69.88252
revision: 2014-12-05
vector
The deep drill holes are used in the exploration. Additional information about the bedrock of the target area, about its structure and about its geochemical composition is obtained from the core sample. The deep drillings can be used as basic information for the bedrock mapping, ore exploration, rock and mineral aggregate studies, natural stone research and urban mapping. The dense target scale data can be used in the modeling of geological units and in the preparation of mineral assessment evaluation.
Geological Survey of Finland
email:
geodata@gtk.fi
Role: owner
Data Quality
The deep drill hole data contains mainly diamond drill holes for the use of ore exploration. Some of the holes have been drilled to needs for bedrock mapping, rock and mineral aggregate studies, natural stone research and urban mapping. The material also contains gouge samples, percussion drilling samples and sledge drilling samples. The information has been saved in the Kaira and Loppi information management systems of the GTK. The deep drill hole data of Outokumpu exploration is in a separate information management system as it has been released to the GTK in 2003-2007. Kaira is a information management system which was in use from 1989 to2010 in the Geological Survey of Finland. A significant part of the deep drill hole data during the time period was saved in it. Drilling data reported in the paper forms was saved in Kaira afterwards when necessary. Before 2010 the fields of the data systems did not usually have value lists. Kaira also contained drilling data from the exploration companies like Outokumpu and Rautaruukki. In 2010 the data in Kaira was transferred to the present drilling information management system of Geotietoydin. At the transfer stage the data of 19 124 drill holes was in Kaira. Loppi is Access database which was in use from 2005 to 2011 for the purpose to manage the GTK’s national drill core archive in Loppi. The database was in the past system which was based on the WordPerfect files in the DOS operating system. It was replaced in 2005 with Microsoft Access 2000 database. The Loppi information management system contained information about the archived core samples for altogether 137 sender organizations. The database contained the location of drill holes, the azimuth and the dip of the drill holes, the information about a sender and drilling organization and the location of the core sample in the drill core archive. In 2011 this separate information management system was merged as part of the drilling information management system of Geotietoydin. At the transfer stage there was the information of 36 225 drill holes in the Loppi database. The drilling data collected in GTK is planned and saved with rugged tablet PC to a personal geodatabase from the year 2010 onwards. The data from personal geodatabase is imported to the drilling information management system of Geotietoydin. The saving of information is based on hierarchical value lists in accordance with accepted standards. The positioning accuracy of the drill holes and the content of the data varies. Before the year 1998 the drilling sites were positioned with a compass and on the basis of more recent material then available from the National Land Survey of Finland (NLS) such as economic maps at a scale of 1:100 000, base or topographic maps at a scale of 1:20 000 as well as black and white or false colour aerial photographs and aerial photography maps. Line staking that was drawn to the drilling site or tachymeter was used on demand more exact position accuracy. Since the year 1998 the drilling sites have been positioned with the help of the GPS device. The use of the device was established in 2000. When better position accuracy is required a differential GPS or geodesic GPS is used. The azimuth can be determined with a compass or GPS device. If more precise information is required, the azimuth can be measured with specific equipment like Maxibor. The dip of the drill hole is either set by the drilling machine or measured with specific equipment like Maxibor. The measuring device or its part is moved down the hole and the dip and azimuth are measured by the even distances. The drilling contractor mark a hole length on the box on the basis of the drilling rods. In the length of the hole a soil drilling is taken into consideration. The length of the hole is measured again during the core logging, and the core losses and fractures will be taken into consideration. In 1952-2003, Outokumpu Oy made deep drill holes related to the ore exploration. The company released exploration data to GTK in 2003-2007 in the data transfer project. During the project also the data from Rautaruukki Oy and Lapin Malmi was transferred. The positioning accuracy of the drill holes and the collected data content vary. Before the year 2000 the observations were located on the basis of a compass and a topographic map or basic map, line staking or the tachymeter. After the year 2000 the positioning was determined with the GPS device.
Equivalent Scale:
1:
1000
COMMISSION REGULATION (EC) No 1205/2008 of 3 December 2008 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards metadata
Constraints
The drilling information should not be used for purposes which require special studies, such as the drawing up of ore estimates or the different urban engineering projects. User must pay attention to inaccuracies related to the positioning method before the introduction of the GPS device and to the analysis data for the older materials.
© Geologian tutkimuskeskus
© Geologian tutkimuskeskus
Metadata about metadata
573c5f70-e010-4c99-bb62-43500a010855
Geological Survey of Finland
PL 96 (Betonimiehenkuja 4),
ESPOO,
02150
tel: 0295030000
email:
geodata@gtk.fi
Role: point of contact
2016-05-19