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| | RESULTS |
 | | Matrix calcite generally decreases in abundance downcore, whereas the siliciclastic minerals (quartz and plagioclase), and minerals of diagenetic or hydrothermal origin (chlorite, analcime, and serpentine) show an increase in downcore abundance within the breccia matrix. |
 | | The downcore transition from Maastrichtian Unit II marine sediments to the top of the Lower Cretaceous Unit IVA breccia (at 853 meters below seafloor [mbsf]) is marked by a sharp decrease in quartz, plagioclase, and chlorite abundances and a sharp increase in the abundance of calcite. |
 | | This abundance change in the matrix mineralogy corresponds to (1) the transition from Subunit IVA to IVB, (2) an increase in fine rock fragments in the matrix (Shipboard Scientific Party, 1998), and (3) a color change of the powdered breccia matrix from predominantly moderate orange pink to variable browns, oranges, and grays (see Table T2). |
| www-odp.tamu.edu /publications/173_SR/chap_01/c1_3.htm (894 words) |
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