leg site hole age mnemonic auxiliary age mnemonic top of section depth(m) bottom of section depth(m) special condition age auxiliary age averaged age age top of section(million years) age bottom of section(million years) average age(million years)t data source 67 494 A QUATERNARY 37.5 189.5 NO AGE GIVEN NO AGE GIVEN 0 1.8 0.9 DSDP INITIAL REPORTS 67 494 A PLIOCENE 189.5 218.0 NO AGE GIVEN NO AGE GIVEN 1.8 5 3.4 DSDP INITIAL REPORTS 67 494 A LOWER PLIOCENE 218.0 223.1 NO AGE GIVEN NO AGE GIVEN 3.4 5 4.2 DSDP INITIAL REPORTS 67 494 A MIDDLE MIOCENE LOWER MIOCENE 223.1 237.0 NO AGE GIVEN NO AGE GIVEN NO AGE GIVEN 10.5 22.5 16.5 DSDP INITIAL REPORTS 67 494 A MIOCENE OLIGOCENE 237.0 240.4 NO AGE GIVEN NO AGE GIVEN NO AGE GIVEN 5 37.5 21.25 DSDP INITIAL REPORTS 67 494 A MIDDLE MIOCENE 240.4 246.5 A LEGITIMATE AGE INVERSION NO AGE GIVEN NO AGE GIVEN 10.5 16 13.25 DSDP INITIAL REPORTS 67 494 A MIDDLE EOCENE 246.5 294.0 NO AGE GIVEN NO AGE GIVEN 43 49 46 DSDP INITIAL REPORTS 67 494 A MAESTRICHTIAN 294.0 303.0 NO AGE GIVEN NO AGE GIVEN 65 70 67.5 DSDP INITIAL REPORTS 67 494 A MIDDLE EOCENE 303.0 303.6 A LEGITIMATE AGE INVERSION NO AGE GIVEN NO AGE GIVEN 43 49 46 DSDP INITIAL REPORTS 67 494 A UPPER CRETACEOUS 303.6 312.5 NO AGE GIVEN NO AGE GIVEN 65 100 82.5 DSDP INITIAL REPORTS 67 494 A MAESTRICHTIAN 312.5 321.5 NO AGE GIVEN NO AGE GIVEN 65 70 67.5 DSDP INITIAL REPORTS