A 1-2 m thick lamprophyre
dyke in Beavertail State Park cross-cuts [S.
More leucocratic lamprophyres
occur as veins within the thick basaltic sills and are made of abundant kaersutite and minor clinopyroxene phenocrysts in a groundmass that consists of alkaline feldspar and devitrified glass.
Moreover, it strikes parallel to numerous smaller dykes of lamprophyres
1977, Differentiation of lamprophyre
magma, Krystalinikum, 13, 73-87.
39]Ar technique and hence to better constrain the age of pre-rifting alkaline magmatism in southeastern New England and establish if it did, indeed, progress from north to south as suggested by other lamprophyre
ages from Avalonia (Fig.
Tournon (1984) reported for the same area an isolated block of picrite instead, and Calero (1987) reported in the Tortugal area a similar ultramafic rock but classified it as lamprophyre
The rock in the second vent is a quartz porphyry which also contains topaz, and there is a long contact zone into which a lamprophyre
1998; Buchan and Ernst 2004), small lamprophyre
, and alkalic rock-carbonatite plugs and dykes, and are overlain by scattered outliers of Proterozoic and Phanerozoic sedimentary cover (see reports listed in Fig.
The Discover Abitibi Initiative (DAI) recently released the results of a lamprophyre
study, designed to determine the diamond bearing potential of lamprophyres
in Timmins, Kirkland Lake and Timiskaming areas.
West of the Otish Mountains and east of James Bay, a smaller rush for diamonds has been underway since last year when Dianor Resources announced in June the discovery of a clear yellow, octahedral to cubic microdiamond in one of the many lamprophyre
dikes in the area.
2011): The lamprophyre
dikes in the Panticosa Pluton (Pyrenean Axial Zone): syn-emplacement with later-hercynian extension.
Prior to the intrusion of the granodiorite stock, steeply dipping east-trending lamprophyre
dykes were discordantly emplaced into the Silurian Kingsclear Group.