SP65 - Blue Hill Dike

Major Element Data

SiO2 TiO2 Al2O3 Fe2O3 FeO MnO MgO CaO Na2O K2O P2O5 Total
45.08 2.18 12.70 2.18 10.49 0.19 10.45 10.76 3.46 1.65 1.04 100.19

(After normalizing for H2O+,L.O.I,and CO2. FeO and Fe2O3 normalized to NNO Buffer.)

Minor Element Data

Rb Sr Ba La Ce Nd Sm Eu Gd Yb Lu Sc Cr Ni Zr Nb Th
23.3 1550 1050 52.5 114 52.4 9.25 2.54 7.21 1.72 0.244 21.7 323 224 192 53 3.94

(PPM)

Rare Earth Element Data

La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
52.500 114.000 52.400 9.250 2.540 7.210 0.867 0.866 0.303 1.720 0.244

(PPM)

Radiogenic Data

87Rb/86Sr error 87Sr/86Sr error 87Sr/86Sri
0.0438 0.0006 0.7044 0.0000 0.7044

147Sm/144Nd error 143Nd/144Nd error EpsilonNd
0.1033 0.0001 0.5126 0.00002 -1.40

206Pb/204Pb error 207Pb/206Pb error 208Pb/206Pb error 207Pb/204Pb error 208Pb/204Pb error
18.0490 0.0130 0.8602 0.0003 2.0957 0.0014 15.5260 0.0160 37.8250 0.0490

(PPM)

Thin Section

Picture of an ocelli in SP65 under crossed-nicols (1mm in diameter).

Thin Section Description

SP65 (Blue Hill Dike). Basalt. This rock is holocrystalline, porphyritic-aphanitic, with medium grained phenocrysts set in a grey-brown groundmass (30%) composed of plagioclase and potassium feldspar. All crystals are subhedral except the opaque minerals (<1 mm) and olivine which are subhedral to anhedral. The following are present as phenocryst phases: normally zoned olivine (3-5 mm); plagioclase (<1 mm); potassium feldspar(<1 mm); analcite (<1 mm); orthopyroxene (<1 mm); augite (<1 mm); apatite (<1 mm); iddingsite (.5 mm) locally replaced by fluorite. Abundant ocelli (1-1.5 mm) are present as circular to subcircular masses with quartz cores rimmed by subhedral acicular clinopyroxene crystals. Some of the olivines are rimmed with clinopyroxene.