_version_ 1867171837734027264
author Rosenthal, Yair
Lohmann, G P
Lohmann, Kyger C
Sherrell, R M
author_facet Rosenthal, Yair
Lohmann, G P
Lohmann, Kyger C
Sherrell, R M
collection Datos científicos de ciencias marinas y ambientales
contents Using bathymetric transects of surface sediments underlying similar sea surface temperatures but exposed to increasing dissolution, we examined the processes which affect the relationship between foraminiferal Mg/Ca and d18O. We found that Globigerinoides saccculifer calcifies over a relatively large range of water depth and that this is apparent in their Mg content. On the seafloor, foraminiferal Mg/Ca is substantially altered by dissolution with the degree of alteration increasing with water depth. Selective dissolution of the chamber calcite, formed in surface waters, shifts the shell's bulk Mg/Ca and d18O toward the chemistries of the secondary crust acquired in colder thermocline waters. The magnitude of this shift depends on both the range of temperatures over which the shell calcified and the degree to which it is subsequently dissolved. In spite of this shift the initial relationship between Mg/Ca and d18O, determined by their temperature dependence, is maintained. We conclude that paired measurements of d18O and Mg/Ca can be used for reconstructing d18Owater, though care must be taken to determine where in the water column the reconstruction applies.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_855384
institution PANGAEA
language en
publishDate 2000
publisher PANGAEA
record_format pangaea
spellingShingle (Table 1) Shell mass and chemistry of Globigerinoides sacculifer
Rosenthal, Yair
Lohmann, G P
Lohmann, Kyger C
Sherrell, R M
0038PG; 0053BC; 0058PG; 0082PG; Area/locality; BC; Box corer; Depth, bathymetric; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; EN06601; EN066-10GGC; EN066-16GGC; EN066-21GGC; EN066-26GGC; EN066-29GGC; EN066-36GGC; EN066-38PG; Endeavor; Event label; GC; Globigerinoides sacculifer; Globigerinoides sacculifer, Magnesium/Calcium ratio; Globigerinoides sacculifer, δ18O; Gravity corer; KN11002; Knorr; KNR110-58; KNR110-82; Mass; Moana Wave; MW9109; MW9109-36BC; MW9109-51BC; MW9109-7BC; OC205-02; OC205-02_0053BC; OC205-02_0057BC; Oceanus; Oceanus205-02; Ontong Java Plateau; Pacific; PC; Piston corer; Providence Channel; Ratio; Reference/source; Standard deviation; Station label; Δ carbonate ion content
Using bathymetric transects of surface sediments underlying similar sea surface temperatures but exposed to increasing dissolution, we examined the processes which affect the relationship between foraminiferal Mg/Ca and d18O. We found that Globigerinoides saccculifer calcifies over a relatively large range of water depth and that this is apparent in their Mg content. On the seafloor, foraminiferal Mg/Ca is substantially altered by dissolution with the degree of alteration increasing with water depth. Selective dissolution of the chamber calcite, formed in surface waters, shifts the shell's bulk Mg/Ca and d18O toward the chemistries of the secondary crust acquired in colder thermocline waters. The magnitude of this shift depends on both the range of temperatures over which the shell calcified and the degree to which it is subsequently dissolved. In spite of this shift the initial relationship between Mg/Ca and d18O, determined by their temperature dependence, is maintained. We conclude that paired measurements of d18O and Mg/Ca can be used for reconstructing d18Owater, though care must be taken to determine where in the water column the reconstruction applies.
title (Table 1) Shell mass and chemistry of Globigerinoides sacculifer
topic 0038PG; 0053BC; 0058PG; 0082PG; Area/locality; BC; Box corer; Depth, bathymetric; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; EN06601; EN066-10GGC; EN066-16GGC; EN066-21GGC; EN066-26GGC; EN066-29GGC; EN066-36GGC; EN066-38PG; Endeavor; Event label; GC; Globigerinoides sacculifer; Globigerinoides sacculifer, Magnesium/Calcium ratio; Globigerinoides sacculifer, δ18O; Gravity corer; KN11002; Knorr; KNR110-58; KNR110-82; Mass; Moana Wave; MW9109; MW9109-36BC; MW9109-51BC; MW9109-7BC; OC205-02; OC205-02_0053BC; OC205-02_0057BC; Oceanus; Oceanus205-02; Ontong Java Plateau; Pacific; PC; Piston corer; Providence Channel; Ratio; Reference/source; Standard deviation; Station label; Δ carbonate ion content
url https://doi.org/10.1594/PANGAEA.855384