(Table 1) Carbon and carbonate at DSDP Leg 71 Holes

Leg 71 sediments were analyzed for total carbon and acid-insoluble (organic) carbon, using the Leco WR-12 analyzer, according to the standard technique outlined below.
The 3 cm**3 sediment samples were first dried and ground into a homogeneous powder. The ground sediment was redried at 105 to 110°C, and two samples, a 0.1 g and a 0.5 g sample, were weighed into Leco clay crucibles. The 0.5 g sample was acidified with 10% hydrochloric acid and washed with distilled water. The sample was then dried and analyzed for acid-insoluble carbon. The 0.1 g sample was analyzed for total carbon without further treatment. If the sample contained less that 10% CaCO3, an additional 0.5 g sample was analyzed for greater accuracy. The calcium carbonate percentages were calculated as follows: (% total C - % organic C) x 8.33 = % CaCO3. Although other carbonates may be present, all acid-soluble carbon was calculated as calcium carbonate.