Norsk versjon
THE NATURAL STONE DATABASE
Occurence 301 - 617 Ravnkollen 1
(Object Id: 15512)
(Last updated: 16.02.2010)

Location
County: Oslo Municipality: Oslo (301)
Map 1:50000: Oslo (1914-4) Map 1:250000: Oslo
Coordinate system: EU89-UTM Zone 32
East: 605339 m. North: 6649050 m.
Longitude: 10.8867640 Latitude: 59.9653140
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Resource
Resource Type: Granite and other igneous rocks Resource Subtype: Syenite
Brickstone(Y/N): N
Importance
Raw material meaning: Little Importance (reg. 18.02.2015)
Historical: Yes , (Confirmed 29.sep.2004 by Leif Furuhaug)

Resources and production
Activity: Stone quarrying Reserves:
Operating method: Open pit mining Historical production:


Deposit rock
Lithology: Weathering colour:
Genesis: Form:
Main texture:
Main grain size: Main alteration:
Strike/Dip: Direction:
Plunge:
Stratigraphic classification of host rock
Era: Period:
Province:
Geotec.unit:
Tectonic complex:
Igneous complex:
Group: Formation:

Information(s) in free text format
Description
Det er brutt ut stein over et større område på platået på toppen av Ravnkollen. Total lengde er 220 m. Det er brutt stein på omtrent hele denne strekningen, men avsenkningen er stort sett mindre enn 1 m. På et mindre område på 10 m x 10 m er det gått lenger ned, avsenkningen er her 3 m.
Location
Flere mindre brudd på toppen av Ravnekollen.

Photo(s) from the Deposit area:
Photo no. 1 showing Bruddområde"

Bibliography:
From NGU's Reference Archive:
Oxaal, John , 1916
Norsk granit
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.76;1-220 pages
Abstract:
This work is a report of granite and the granite industry in Norway. It contains a description of the various fields of granite and similar rocks from a scientific as well as from a technical and economical standpoint. The geological occurrence of the various rocks, their chemical and mineralogical composition, are thoruoughlyoughly treated, also the questions of practical interest, as the quality and other technical properties, further the problems of location and conditions for transport, conditions for quarrying and otherquestions of interest in the utilization of the various occurrences of granite. Granite: This chapter consideres first the mineralogical and chemical composition of the granite, and the various types of granite resulting from the varying composition; thereafter the most important structural types and how these are dependent on the geological appearance of the rock. Lakkolites and other froms assumed by granite masses when injected into the crust of the earth, are mentioned; some examples of beautifully formed lakkolites are also mentioned. The question of sheet structure and rift in the granite are of great importance in its utilization, and are of interest both practically and theoretically.

Name of Locality: Ravnkollen 2
(Object Id: 20442 617,01,00)

Location
County: Oslo Municipality: Oslo (301)
Map 1:50000: Oslo (1914-4) Map 1:250000: Oslo
Coordinate system: EU89-UTM Zone 32
East: 605350 m. North: 6648870 m.
Longitude: 10.8868520 Latitude: 59.9636960
Show on map

Resource
Resource Type: Granite and other igneous rocks Resource Subtype: Syenite
Brickstone(Y/N):
Importance
Historical: Yes , (Confirmed 09.feb.2010 by Leif Furuhaug)

Resources and production
Activity: Stone quarrying Reserves:
Operating method: Open pit mining Historical production:


Information(s) in free text format
Description
Størrelsen på det opprinnelige bruddet er umulig å anslå da det i dag er begravd av rasmasse. Det er fremdeles stor rasfare nær inntil bebyggelse her. Bruddet var drevet til ca. 1960, de siste årene som pukkverk.
Location
Bruddet ligger i nordøstre ende av bebyggelsen på Ammerud rett under en stupbratt fjellside fra Ravnekollen.

Photo(s) from the Deposit area:
Photo no. 1 showing Bruddet"

Name of Locality: Ravnkollen 3
(Object Id: 20443 617,02,00)

Location
County: Oslo Municipality: Oslo (301)
Map 1:50000: Oslo (1914-4) Map 1:250000: Oslo
Coordinate system: EU89-UTM Zone 32
East: 605418 m. North: 6648769 m.
Longitude: 10.8880350 Latitude: 59.9627720
Show on map

Resource
Resource Type: Granite and other igneous rocks Resource Subtype: Syenite
Brickstone(Y/N):
Importance
Historical: Yes , (Confirmed 09.feb.2010 by Leif Furuhaug)

Resources and production
Activity: Stone quarrying Reserves:
Operating method: Open pit mining Historical production:


Information(s) in free text format
Description
Det er her brutt på en groruditt-gang. Bergarten er i sammensetning en granitt, men ser helt annerledes ut (mørk grønn). I steinalderen ble groruditt brukt som erstatning for flint som ikke fantes her i landet. Groruditten er solid og har skarpe kanter, og egnet seg derfor til å lage redskaper av. Derfor har vi mistanke om at dette er et meget gammelt brudd fra vikingetiden.
Location
Bruddet ligger helt syd på Ravnekollen. En vei tar av fra hovedveien til Romsås mot vest og går opp mot Ravnkollen. Bruddet ligger like etter der denne veien tar av.

Photo(s) from the Deposit area:
Photo no. 1 showing Bruddet"

Name of Locality: Ravnkollen 4
(Object Id: 20444 617,03,00)

Location
County: Oslo Municipality: Oslo (301)
Map 1:50000: Oslo (1914-4) Map 1:250000: Oslo
Coordinate system: EU89-UTM Zone 32
East: 605449 m. North: 6648659 m.
Longitude: 10.8885160 Latitude: 59.9617770
Show on map

Resource
Resource Type: Granite and other igneous rocks Resource Subtype: Syenite
Brickstone(Y/N):
Resources and production
Activity: Stone quarrying Reserves:
Operating method: Open pit mining Historical production:


Information(s) in free text format
Description
Størrelsen er ca. 10 m x 10 m og 5 m avsenkning. Bruddet ligger i en bratt skrent, og mye stor blokk er rast ned i bunnen.
Location
Bruddet er beliggende lengst sør på Ravnekollen øst for Ammerud.

Photo(s) from the Deposit area:
Photo no. 1 showing Bruddet"


The fact sheet was created on 08.12.2021

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