Lakes volcanic

The trace element patterns in Figure 4 are similar to komatiites of the Kidd-Munro assemblage, whose negative HFSE were interpreted by %man (1999) to be a result of contamination by other HFSE-depleted rock. If Big Lake volcanic rocks are plume-derived, their negative HFSE depletions could similarly be explained by country arc rock contamination in lavas or parent magma chambers. 

Francis D. (1987) Mantle-melt interaction recorded in spinel Iherzolite xenoliths from the Alligator Lake Volcanic Complex, Yukon, Canada. J. Petrol. 28, 569-597. 

The most significant deposits are in southern Nevada, in the Lake Mead area, and in the McDermitt caldera complex on the Nevada—Oregon border. In the McDermitt caldera, lithium probably originated from volcanic sedimentary rocks deposited in the caldera moat. There is evidence that areas of the caldera were hydrothermically active contributing to enrichment of lithium (14). This and other similar deposits are not economically viable as of this writing. These deposits do represent a significant lithium reserve, however, whenever large expansion in demand occurs. 

The SSI (solid-state imaging) camera on board the Galileo spacecraft transmitted impressive high-resolution pictures of Io s volcanic activity. Active lava lakes, lava curtains , calderas, mountains and plateaus can be seen (McEwen et al., 2000). The Hubble telescope detected both S2 gas and SO2 in a SO2 to S2 ratio of 1 4 in the smoke trail of the volcano Pele. This value suggests an equilibrium between silicate magmas in the neighbourhood of the quartz-fayalite-magnetite buffer (see Sect. 7.2.2). 

The oldest of these sedimentation rates, Region I (150 g m 2 yr-1 or 0.063 cm yr-1) represents natural or the pre-cultural sedimentation rates before 1889. Near this location in the lake a volcanic ash layer overlain by 480 cm of sediment has been found, Gould and Budinger [15]. Radiocarbon dating of... 

Powers, H. A., Wilcox, R. E., Volcanic ash from Mount Mazama (Crater Lake) and from Glacier Park. Science, 144, 1334-1336 (1964). 

Treasure Lake Group, overlain by felsic ignimbrite sheets of the Faber Group (Goad et al. 2000). Ore minerals mainly consists of Fe-, As-, Co- and Cu-sulphides, native Au and Bi. Intense, pervasive, polyphase iron-oxide (magnetite-dominant)-hornblende-biotite-tourmaline-K-feldspar-carbonate replacive alteration occurs in the upper metasedimentary sequence below the volcanic-sedimentary unconformity... 

Bailes, A.H. Galley, A.G., 1999. Evolution of the Paleoproterozoic Snow Lake arc assemblage and geodynamic setting for associated volcanic-hosted massive sulphide deposits, Flin Flon Belt, Manitoba, Canada. Canadian Journal of Earth Sciences, 36, 1789-1805. 

The Halfmile Lake deposit consists of massive, breccia, and stockwork Zn-Pb-Cu sulfide mineralization hosted by volcanic and sedimentary rocks of the Ordovician Tetagouche Group (Mireku Stanley 2006 Adair 1992). The main sulphide minerals in the deposit are... 

The Big Lake Cu-Zn-Ag-Au voicanogenic massive sulphide (VMS) occurrence is hosted in mafic-ultramafic strata of the Schreiber-Hemio greenstone belt near Marathon, Ontario (Fig. 1). This VMS is unusual in that it is one of a few documented VMS occurrences in sequences lacking felsic volcanic or volcaniclastic rock. 

The Boucher Brook Formation is the upper-most unit in the California Lake Group and consists of grey shale, siltstone, chert, alkalic basalt, and minor peralkaline felsic volcanic rocks including the alkaline basalt of the Camel Back Member (Fig. 1). 

Fig 1. Regional geology map of the Victoria Lake Supergroup showing the Tulks Volcanic Belt occurring from the south west to the north central part of the map area. Also shown are the other volcanogenic massive sulfide deposits (modified from Hinchey 2007). 

The Maze Lake area is underlain primarily by massive mafic volcanic flows and lesser pillowed, and amygdaloldal flows and tuffaceous rocks In the southern and central portions of the property, and along the extreme northern edge. Minor... 

The oldest supracrustal rocks are mafic volcanics and sedimentary rocks of the 2100-2000 Ma Moran Lake and Post Hill groups, believed to have formed as a... 

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