scholarly journals Airborne geophysical survey, Flin Flon-Hanson Lake area, Saskatchewan

1996 ◽  
Author(s):  
R B K Shives ◽  
R J Hetu ◽  
P B Holman
1999 ◽  
Vol 36 (2) ◽  
pp. 293-312 ◽  
Author(s):  
Kevin M Ansdell ◽  
Karen A Connors ◽  
Richard A Stern ◽  
Stephen B Lucas

Lithological and structural mapping in the east Wekusko Lake area of the Flin Flon Belt, Trans-Hudson Orogen, suggested an intimate relationship between magmatism, fluvial sedimentation, and initiation of fold and thrust belt deformation. Conventional U-Pb geochronology of volcanic rocks in fault-bounded assemblages provides a minimum age of 1876 ± 2 Ma for McCafferty Liftover back-arc basalts, and ages of between 1833 and 1836 Ma for the Herb Lake volcanic rocks. A rhyolite which unconformably overlies Western Missi Group fluvial sedimentary rocks has complex zircon systematics. This rock may be as old as about 1856 Ma or as young as 1830 Ma. The sedimentary rocks overlying this rhyolite are locally intercalated with 1834 Ma felsic volcanic rocks, and yield sensitive high resolution ion microprobe (SHRIMP) U-Pb and Pb-evaporation detrital zircon ages ranging from 1834 to 2004 Ma. The Eastern Missi Group is cut by an 1826 ± 4 Ma felsic dyke, and contains 1832-1911 Ma detrital zircons. The dominant source for detritus in the Missi Group was the Flin Flon accretionary collage and associated successor arc rocks. The fluvial sedimentary rocks and the Herb Lake volcanic rocks were essentially coeval, and were then incorporated into a southwest-directed fold and thrust belt which was initiated at about 1840 Ma and active until at least peak regional metamorphism.


1987 ◽  
Vol 24 (11) ◽  
pp. 2305-2315 ◽  
Author(s):  
Pradeep K. Aggarwal ◽  
Bruce E. Nesbitt

Estimates of pressure and temperature conditions of metamorphism in the vicinity of three massive sulfide deposits of the Flin Flon – Snow Lake, Manitoba, greenstone belt have been obtained using mineral assemblages in mafic and felsic metavolcanic rocks. The Flin Flon area around the Centennial deposit, in the western part of the belt, has been metamorphosed to low greenschist facies. Near the Spruce Point deposit, in the central part of the belt, the metamorphic conditions are estimated to be of the upper greenschist facies, with a temperature of 475 ± 75 °C at 2.6 ± 1.2 kbar pressure (1 kbar = 0.1 kPa). The Snow Lake area to the west, in the vicinity of the Anderson Lake deposit, has been metamorphosed to sillimanite grade. In the staurolite–biotite–sillimanite zone, the temperature and pressure conditions were 580 ± 25 °C and 5.25 + 0.75 kbar; in the biotite–sillimanite–almandine zone, the temperature was 620 ± 25 °C at a maximum pressure of 6.2 kbar. Based on the temperature and pressure estimates from the Snow Lake area, it is suggested that experimental studies of the upper stability of staurolite and quartz at low pressure indicate temperatures that are unusually high compared with those indicated by field assemblages.


1972 ◽  
Vol 9 (5) ◽  
pp. 500-513 ◽  
Author(s):  
D. F. Sangster

Lead isotope abundances in 4 stratabound sulfide ores are presented and show characteristics of being single-stage lead deposits. Model ages based on these data range from 1780 ± 44 to 1900 ± 44 m.y. and are considered to be close approximations of the time of ore formation. Geological evidence in the massive sulfide deposits suggests they are coeval with their host rocks, which are predominantly volcanics of the Amisk Group. If this assumption is correct the average model lead age of the ores is essentially the age of the enclosing rocks. Within error limits the results are in good agreement with published Rb-Sr ages for Amisk rocks of the Flin Flon area, and with U-Pb ages in zircons of rhyolites, which also contain similar, massive sulfide ores in the Churchill Province of Arizona. This is considered to be good evidence that the Hanson Lake-Flin Flon-Snow Lake volcanic mineral belt, previously regarded as Archean, is Aphebian in part.A previously published Archean, Rb-Sr isochron for volcanic rocks in the Hanson Lake area may indicate that Amisk-type rocks are a folded complex of both Aphebian and Archean lithologies. The suggested Aphebian age of the Amisk-Missi Groups and their equivalents, indicates they are possibly eugeosynclinal equivalents of the miogeosynclinal Hurwitz sediments.


1994 ◽  
Vol 31 (12) ◽  
pp. 1785-1790 ◽  
Author(s):  
J. David ◽  
E. C. Syme

The Flin Flon volcanic belt of the Trans-Hudson Orogen in northern Manitoba comprises magmatic rocks (1.88 – 1.90 Ga) generated in an intra-oceanic arc and identified as one of the best examples of juvenile Paleoproterozoic crust. In the Flin Flon – Athapapuskow Lake area, the belt consists of a series of fault-bounded blocks, each having distinct stratigraphic and magmatic affinities, juxtaposed to form an accretionary collage. Two tonalitic bodies within the Northeast Arm shear zone, a major deformation corridor separating two of the most important blocks in the area, have been dated by the U–Pb zircon method at [Formula: see text] and [Formula: see text]. These results indicate the presence of fragments of late Neoarchean crust within the Flin Flon belt, possibly related to ca. 2.5 Ga granitic bodies found in terranes beyond the western limit of the belt. The presence of ca. 2.5 Ga tonalites within the Flin Flon Belt, herein reported for the first time, has major implications for basement involvement in the early tectonic evolution of the Flin Flon Belt.


1999 ◽  
Vol 36 (11) ◽  
pp. 1843-1857 ◽  
Author(s):  
Martin Parent ◽  
Nuno Machado ◽  
Herman Zwanzig

The Kisseynew domain is the central unit of the Reindeer Zone of the Paleoproterozoic Trans-Hudson Orogen, in Manitoba and Saskatchewan. The southern flank of the domain is a transition zone between the greenschist facies of the volcano-plutonic assemblage of the Flin Flon - Snow Lake belt and the upper amphibolite facies of Kisseynew paragneisses. The Jungle Lake area, in the southern flank of the Kisseynew Domain, comprises mainly quartzofeldspathic gneisses representing continental clastic units of the Missi suite and migmatitic metagraywackes of the Burntwood suite. The area was affected by several phases of deformation, metamorphism, and migmatisation. Detailed mapping and U-Pb geochronology were carried out in order to establish the timing of the deformational and metamorphic phases. The oldest leucosome contains sillimanite formed during peak metamorphism and is associated with F2 folding and S2 fabric. Five single monazites from this leucosome yield ages between 1809 and 1803 Ma taken as the best estimate for the duration of peak metamorphism. Biotite schlieren in diatexites in the Burntwood suite show a S2 fabric folded by F3. Zircon from one of these diatexites yield a crystallization age of 1798+3-2 Ma, considered as the lower limit for the F2 event. Single monazites from the same rock yield ages between 1812 and 1789 Ma, the oldest of which are considered to be inherited. The youngest mobilisate is a pegmatite crosscutting F2 and F3 fabrics and yielded single monazite ages between 1875 and 1788 Ma. The youngest age is taken as the age of the pegmatite and is a minimum age for F3 fabrics. These results, together with those from other areas of the southern Kisseynew Domain, indicate a ca. 30 million year period (1818 and 1785 Ma) of continuous deformation and metamorphism. The data also show the presence of monazite crystals of different ages in the same rock illustrating the need to analyse single grains to obtain geologically meaningful ages.


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