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Science EducationVolume 59, Issue 1 p. 51-58 Science Teacher Education The training of science teachers in Sierra Leone Ronald J. Raven, Ronald J. Raven Science Editor Lecturer, Department of Education, Fourah Bay College, University of Sierra Leone, Freetown, Sierra Leone, AfricaSearch for more papers by this authorEbun Sawyerr, Ebun Sawyerr Lecturer, Department of Education, Fourah Bay College, University of Sierra Leone, Freetown, Sierra Leone, AfricaSearch for more papers by this author...
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Eight garnet peridotite and ten garnet-free peridotite xenoliths from the Lashaine volcano in northern Tanzania, and one garnet peridotite from the Matsoku pipe in Lesotho, were studied petrographically and by electron-microprobe techniques. The primary assemblages are ol + opx + cpx + ga, ol + opx + cpx + chr, ol + opx + ga + chr, ol + opx + ga, ol + opx + chr, and ol + cpx + chr. With the exception of the ol + cpx + chr assemblage, which is more iron-rich, the composition of each of the...
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Eight garnet peridotite and ten garnet-free peridotite xenoliths from the Lashaine volcano in northern Tanzania, and one garnet peridotite from the Matsoku pipe in Lesotho, were studied petrographically and by electron-microprobe techniques. The primary assemblages are ol + opx + cpx + ga, ol + opx + cpx + chr, ol + opx + ga + chr, ol + opx + ga, ol + opx + chr, and ol + cpx + chr. With the exception of the ol + cpx + chr assemblage, which is more iron-rich, the composition of each of the...
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Whole rock analyses and selected trace element data are reported for nineteen, extremely fresh, peridotite xenoliths, together with the host ankaramite and associated carbonatite tuff, sampled from the Lashaine volcano in northern Tanzania. For comparison, data for a garnet peridotite from Matsoku in eastern Lesotho are included. These xenoliths are inferred to be derived from the garnet peridotite zone of the upper mantle from depths of about 150 km. The chemical data indicate that, despite...
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Whole rock analyses and selected trace element data are reported for nineteen, extremely fresh, peridotite xenoliths, together with the host ankaramite and associated carbonatite tuff, sampled from the Lashaine volcano in northern Tanzania. For comparison, data for a garnet peridotite from Matsoku in eastern Lesotho are included. These xenoliths are inferred to be derived from the garnet peridotite zone of the upper mantle from depths of about 150 km. The chemical data indicate that, despite...
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Rare-earth elements (REE) Rb, Sr and Ba have been determined in three garnet peridotites and a spinel peridotite that occur as xenoliths in ankaramite at Lashaine volcano. These element data have also been determined for the ankaramite and a closely associated carbonatite. Three peridotites have light REE-fractionated patterns, variable Rb, Sr and Sr87/Sr86 values which are consistent with mixing of peridotite with ankaramite. However, bulk contamination by either ankaramite or carbonatite...
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Rare-earth elements (REE) Rb, Sr and Ba have been determined in three garnet peridotites and a spinel peridotite that occur as xenoliths in ankaramite at Lashaine volcano. These element data have also been determined for the ankaramite and a closely associated carbonatite. Three peridotites have light REE-fractionated patterns, variable Rb, Sr and Sr87Sr86 values which are consistent with mixing of peridotite with ankaramite. However, bulk contamination by either ankaramite or carbonatite is...