| _version_ | 1867169669573509120 |
|---|---|
| author | Stein, Ruediger Sarnthein, Michael |
| author_facet | Stein, Ruediger Sarnthein, Michael |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | At DSDP Hole 544B, oxygen-isotope stratigraphy, carbonate proportion, clay mineralogy, and (terrigenous) grain sizes show short-term (Milankovitch-type) sediment cycles from 5.1 m.y. to the present and fairly uniform conditions of deposition before this date. The cycles are superimposed by two large-scale shifts of sediment composition and flux parallel to distinct changes of the average benthos delta18O composition (up to 0.7‰). The shifts coincide with major hiatuses from 1.05 to 1.65 and from 2.4 to 4.5 m.y. and can be correlated with specific events of the global climatic evolution. The marked increase in the proportion of chlorite and in the grain-sizes of terrigenous matter near 2.4 m.y. may reflect increased physical weathering and denudation of the Atlas Mountains and the lowering of sea level. These hiatuses were probably formed by strengthened contour currents that also may have caused the reduction of both terrigenous and calcium-carbonate flux rates during the Brunhes Magnetic Epoch. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_267747 |
| institution | PANGAEA |
| language | en |
| publishDate | 2004 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Stable isotope ratios of benthic foraminifera from DSDP Hole 79-544B (Table 1) Stein, Ruediger Sarnthein, Michael 79-544B; Cibicidoides wuellerstorfi, δ13C; Cibicidoides wuellerstorfi, δ18O; Deep Sea Drilling Project; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Glomar Challenger; Leg79; Mass spectrometer VG Micromass 602; North Atlantic/PLATEAU; Pyrgo murrhina, δ13C; Pyrgo murrhina, δ18O; Sample code/label; Uvigerina finisterrensis, δ13C; Uvigerina finisterrensis, δ18O; Uvigerina peregrina, δ13C; Uvigerina peregrina, δ18O; Uvigerina sp., δ13C; Uvigerina sp., δ18O; Uvigerina spp., δ13C; Uvigerina spp., δ18O At DSDP Hole 544B, oxygen-isotope stratigraphy, carbonate proportion, clay mineralogy, and (terrigenous) grain sizes show short-term (Milankovitch-type) sediment cycles from 5.1 m.y. to the present and fairly uniform conditions of deposition before this date. The cycles are superimposed by two large-scale shifts of sediment composition and flux parallel to distinct changes of the average benthos delta18O composition (up to 0.7‰). The shifts coincide with major hiatuses from 1.05 to 1.65 and from 2.4 to 4.5 m.y. and can be correlated with specific events of the global climatic evolution. The marked increase in the proportion of chlorite and in the grain-sizes of terrigenous matter near 2.4 m.y. may reflect increased physical weathering and denudation of the Atlas Mountains and the lowering of sea level. These hiatuses were probably formed by strengthened contour currents that also may have caused the reduction of both terrigenous and calcium-carbonate flux rates during the Brunhes Magnetic Epoch. |
| title | Stable isotope ratios of benthic foraminifera from DSDP Hole 79-544B (Table 1) |
| topic | 79-544B; Cibicidoides wuellerstorfi, δ13C; Cibicidoides wuellerstorfi, δ18O; Deep Sea Drilling Project; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Glomar Challenger; Leg79; Mass spectrometer VG Micromass 602; North Atlantic/PLATEAU; Pyrgo murrhina, δ13C; Pyrgo murrhina, δ18O; Sample code/label; Uvigerina finisterrensis, δ13C; Uvigerina finisterrensis, δ18O; Uvigerina peregrina, δ13C; Uvigerina peregrina, δ18O; Uvigerina sp., δ13C; Uvigerina sp., δ18O; Uvigerina spp., δ13C; Uvigerina spp., δ18O |
| url | https://doi.org/10.1594/PANGAEA.267747 |