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| | MIDDLE PROTEROZOIC A-TYPE GRANITE PLUTONISM IN THE WESTERN HUDSON HIGHLANDS, NEW YORK (Site not responding. Last check: 2007-10-09) |
 | | The geochemistry of 30 samples of Middle Proterozoic granites and granitic gneisses from the western Hudson Highlands, southeastern New York were investigated in order to understand their petrogenesis in relation to deformation and tectonic events within this part of the Grenville orogenic belt. |
 | | Western Hudson Highlands granites and granitic gneisses are metaluminous to peraluminous granites (ASI=0.9 to 1.1) with almost all having a A-type chemical characteristics defined by high K/Na (1-3), Ba/Sr (2-10), Fe/(Fe+Mg) (0.82-0.90), Ba (500-1500 ppm), Zr (350-900 ppm), Y (75-150 ppm), and low Sr, (100-200 ppm), MgO (<0.8%), CaO (<2%), Cr and Ni (<5 ppm). |
 | | Given the abundance of felsic gneisses in the Hudson Highlands, tonalitic to granodioritic source rocks are the likely anatectic source for the granites. |
| gsa.confex.com /gsa/2001NE/finalprogram/abstract_2840.htm (502 words) |
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