Controls on the Occurrence and Distribution of Tungsten and Lithium Deposits on the Southeast Margin of the Leinster Granite, Ireland

Deformational and stratigraphic influences on mineralization in SE Ireland

“…The authors recognize (McArdle and Kennan 1988) that certain lithological sequences are significantly related to the development of mineralization in SE Ireland in that they seem to have contained a variety of metals available for tapping by later structural and intrusive events. Though the most obvious feature of the various deposits is their association with the granite contact, the intrusion of the granite of itself would not have resulted in mineralization if metals had not been available to be scavenged.…”

“…McArdle and Kennan (1988) noted that the tungsten metal deposits around Ballinglen are also spatially related to a coticule-bearing sequence. Gallagher (1989) disputes the importance of a lithological control noting that tungstenbearing microtonalite sheets at Ballinglen occur over a 2 km stratigraphic thickness whereas coticule has a much more restricted stratigraphic range.…”

“…Scheelite is, in fact, widely present in the granitic rocks of the district (Steiger and Bowden 1982;McArdle 1984). However, if very minor scheelite occurrences are discounted, it is clear that the microtonalite-hosted scheelite and that hosted in country rock shows an excellent stratigraphic coincidence (McArdle and Kennan 1988). The coticule is not the source of metal but it is a distinctive minor component of the source-rock sequence.…”

“…400 Ma Leinster Granite in SE Ireland (Kennan 1978;Williams and Kennan 1983;Kennan etal. 1986;Appleby and Williams 1988;McArdle and Kennan 1988;Gallagher 1989;McArdle et al 1989 a). Though there is as yet no clear definition of the time interval separating intrusion and mineralization, what evidence there is suggests that the interval is short ).…”

“…In the case of lead-zinc vein mineralization, the role of the Leinster Granite has come to be seen as providing the energy to drive convecting, metal-leaching, hydrothermal systems in its envelope. Hand in hand with this conceptual evolution, increasing recognition has been given to the influence of deformation on the siting of, in particular, deposits of scheelite and lithium (McArdle and Kennedy 1985;McArdle and Kennan 1988).…”