Publication Date:
2023-07-09
Description:
Diverse and abundant late Miocene to Pleistocene silicoflagellates at DSDP Site 504 can be correlated by tropical biostratigraphic zones and relative paleotemperature values to eastern tropical Pacific reference site DSDP 503A farther to the west. Early Pliocene assemblages, which were poorly known until now, are present and can be correlated locally between DSDP Holes 504, 503A, and 495, using species events associated with the new Dictyocha pulchella Subzone and Dictyocha angulata Subzone. Silicoflagellate relative paleotemperature values show major warming at 4.7 to 5.0 Ma (Cores 45-48), 3.4 to 3.8 Ma (Cores 32-33), 1.5 to 1.7 Ma (Cores 12-16), and 0.5 to 0.8 Ma (Cores 3-6). Major coolings occurred at 5.0 to 5.1 Ma (Core 51), 3.9 to 4.4 Ma (Cores 38-44), and 1.0 to 1.3 Ma (Cores 8-10). The appearance of Dictyocha longa is proposed to replace the asperoid/fibuloid ratio reversal as the bottom of the Dictyocha fibula Zone, because the non-evolutionary ratio reverses several times in the upper Miocene of Hole 503A, and at least once in Hole 504. Three new Pliocene silicoflagellates are defined: Dictyocha concinna Bukry, n. sp., D. helix Bukry, n. sp., and D. tamarae Bukry, n. sp.
Keywords:
-; 69-504; Calculated; Counting, silicoflagellates; Deep Sea Drilling Project; DEPTH, sediment/rock; Dictyocha aculeata; Dictyocha angulata; Dictyocha aspera; Dictyocha aspera aspera; Dictyocha aspera clinata s. ampl.; Dictyocha brevispina; Dictyocha calida ampliata; Dictyocha calida calida; Dictyocha concavata; Dictyocha concinna; Dictyocha delicata; Dictyocha delicata var. bisecta; Dictyocha fibula s. ampl.; Dictyocha helix; Dictyocha longa; Dictyocha longa var. paxilla; Dictyocha neonautica var. cocosensis; Dictyocha ornata africana; Dictyocha perfecta; Dictyocha perlaevis; Dictyocha perlaevis flexatella; Dictyocha perlaevis perlaevis; Dictyocha perlaevis perlaevis s. ampl.; Dictyocha pulchella; Dictyocha sp.; Dictyocha spp.; Dictyocha stapedia aspinosa; Dictyocha stapedia stapedia; Dictyocha subaculeata; Dictyocha tamarae; Dictyocha transenna; Dictyocha varia; Dictyocha vexativa; Distephanus boliviensis; Distephanus crux bispinosus; Distephanus crux carolae; Distephanus crux crux s. ampl.; Distephanus major; Distephanus mesophthalmus; Distephanus polyactis; Distephanus quinquangellus; Distephanus sp.; Distephanus speculum bispicatus; Distephanus speculum elongatus; Distephanus speculum forma coronata; Distephanus speculum minutus; Distephanus speculum speculum; Distephanus speculum tenuis; Distephanus spp.; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Epoch; Glomar Challenger; Leg69; Mesocena circulus; Mesocena diodon nodosa; Mesocena quadrangula; Mesocena sp.; Mesocena triodon; Octactis pulchra; Sample code/label; Silicoflagellate zone; Specimen count
Type:
Dataset
Format:
text/tab-separated-values, 3974 data points
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