Gespeichert in:
| Hauptverfasser: | , |
|---|---|
| Format: | Dataset Open Access |
| Sprache: | en |
| Veröffentlicht: |
PANGAEA
1991
|
| Schlagworte: | |
| Online-Zugang: | https://doi.org/10.1594/PANGAEA.733942 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1867167662582267904 |
|---|---|
| author | Prell, Warren L Farrell, John W |
| author_facet | Prell, Warren L Farrell, John W |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | The Pliocene-Pleistocene history of CaCO3 preservation in the central equatorial Pacific is reconstructed from a suite of deep-sea cores and is compared to fluctuations in global ice volume inferred from delta18O records. The results are highlighted by: (1) a strong covariation between CaCO3 preservation and ice volume over 104 to 106 year time scales; (2) a long-term increase in ice volume and CaCO3 preservation since 3.9 Ma demonstrated by a deepening of the lysocline and the carbonate critical depth; (3) a dramatic shift to greater CaCO3 preservation at 2.9 Ma; (4) distinctive ice-volume growth and CaCO3 preservation events at 2.4 Ma, which are associated with the significant intensification of northern hemisphere glaciation; (5) a mid-Pleistocene transition to 100-kyr cyclicity in both CaCO3 preservation and ice volume; and (6) a 600-kyr Brunhes dissolution cycle superimposed on the late Pleistocene glacial/interglacial 100-kyr cycles. CaCO3 preservation primarily reflects the carbonate chemistry of abyssal waters and is controlled by long-term (106 year) and short-term (104 to 105 year) biogeochemical cycling and by distinct paleoclimatic events. We attribute the long-term increase in CaCO3 preservation primarily to a fractionation of CaCO3 deposition from continental shelf to ocean basin, and secondarily to a gradual rise in the riverine and glaciofluvial flux of Ca++. On shorter time scales, the fluctuations in CaCO3 preservation slightly lag ice volume fluctuations and are attributed to climatically induced changes in the circulation and chemistry of Pacific deep water. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_733942 |
| institution | PANGAEA |
| language | en |
| publishDate | 1991 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Calcium carbonate preservation in the equatorial Pacific Prell, Warren L Farrell, John W 85-572A; 85-572C; 85-573A; 85-574; Albatross IV (1963); core_59; core_60; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; GC; Glomar Challenger; Gravity corer; Lamont-Doherty Earth Observatory, Columbia University; LDEO; Leg85; Melville; MN76-01, Pleiades; NODC-0418; North Pacific/TROUGH; North Pacific Ocean; Pacific Ocean; PC; Piston corer; PLDS-130P; PLDS-4; RC11; RC1112; RC11-209; RC11-210; RC12; RC12-63; RC12-65; RC12-66; Robert Conrad; SDSE_090; SDSE_092; SwedishDeepSeaExpedition; V24; V24-55; V24-58; V24-59; V24-62; V28; V28-179; Vema; W8402A; W8402A-14; Wecoma The Pliocene-Pleistocene history of CaCO3 preservation in the central equatorial Pacific is reconstructed from a suite of deep-sea cores and is compared to fluctuations in global ice volume inferred from delta18O records. The results are highlighted by: (1) a strong covariation between CaCO3 preservation and ice volume over 104 to 106 year time scales; (2) a long-term increase in ice volume and CaCO3 preservation since 3.9 Ma demonstrated by a deepening of the lysocline and the carbonate critical depth; (3) a dramatic shift to greater CaCO3 preservation at 2.9 Ma; (4) distinctive ice-volume growth and CaCO3 preservation events at 2.4 Ma, which are associated with the significant intensification of northern hemisphere glaciation; (5) a mid-Pleistocene transition to 100-kyr cyclicity in both CaCO3 preservation and ice volume; and (6) a 600-kyr Brunhes dissolution cycle superimposed on the late Pleistocene glacial/interglacial 100-kyr cycles. CaCO3 preservation primarily reflects the carbonate chemistry of abyssal waters and is controlled by long-term (106 year) and short-term (104 to 105 year) biogeochemical cycling and by distinct paleoclimatic events. We attribute the long-term increase in CaCO3 preservation primarily to a fractionation of CaCO3 deposition from continental shelf to ocean basin, and secondarily to a gradual rise in the riverine and glaciofluvial flux of Ca++. On shorter time scales, the fluctuations in CaCO3 preservation slightly lag ice volume fluctuations and are attributed to climatically induced changes in the circulation and chemistry of Pacific deep water. |
| title | Calcium carbonate preservation in the equatorial Pacific |
| topic | 85-572A; 85-572C; 85-573A; 85-574; Albatross IV (1963); core_59; core_60; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; GC; Glomar Challenger; Gravity corer; Lamont-Doherty Earth Observatory, Columbia University; LDEO; Leg85; Melville; MN76-01, Pleiades; NODC-0418; North Pacific/TROUGH; North Pacific Ocean; Pacific Ocean; PC; Piston corer; PLDS-130P; PLDS-4; RC11; RC1112; RC11-209; RC11-210; RC12; RC12-63; RC12-65; RC12-66; Robert Conrad; SDSE_090; SDSE_092; SwedishDeepSeaExpedition; V24; V24-55; V24-58; V24-59; V24-62; V28; V28-179; Vema; W8402A; W8402A-14; Wecoma |
| url | https://doi.org/10.1594/PANGAEA.733942 |