Reconnaissance for Mississippi Valley-type and SEDEX Zn-Pb deposits in the Franklinian Basin, Eastern North Greenland. Results of the 2013 Season

Exploration reconnaissance carried out by the Geological Survey of Denmark and Greenland (GEUS) in southern Peary Land, during the summer of 2013, allowed for the identification of two new multi-locality Mississippi-Valley Type showings, and to further expand one showing identified in 2012. In contrast, SEDEX mineralisation was unsuccessfully searched for in Amundsen Land.

The Mississippi-Valley Type (MVT) mineralisation consists of sphalerite and/or galena, occasionally fluorite or barite, in white calcite veinlets and breccias hosted in the Turesø Formation dolostones (Upper Ordovician to Lower Silurian - Morris Bugt Group), of the Franklinian Basin carbonate platform. The highest grades recorded in in situ grab samples are 6.79 % Zn and 36.1 % Pb. Mineralisation is present in three distinct horizons:
- within the lowermost pale-weathering Lower Turesø Formation, ~10 m above the contact with the Børglum River Formation;
- within the lowermost dark-weathering Upper Turesø Formation,~80 m below the contact with the Ymers Gletcher Formation;
- within the dark-weathering Upper Turesø Formation, ~50 m below the contact with the Ymers Gletcher Formation.

Of these three horizons, the intermediate one is the best represented and is therefore interpreted as being the most continuous.