A controversial aspect of Pliocene (5.3–2.6 Ma) climate is whether El Niño‐like (El Padre) conditions, characterized by a reduced trans‐equatorial sea‐surface temperature (SST) gradient, prevailed across the Pacific. Evidence for El Padre is chiefly based on reconstructions of sea‐surface conditions derived from the oxygen isotope (δ18O) and Mg/Ca compositions of shells belonging to the planktic foraminifer
The use of secondary ion mass spectrometry (SIMS) to perform micrometer‐scale
Paired SIMS and GSMS δ13C values measured from final chamber fragments of the same shell of the planktic foraminifer
Paired analyses of cleaned fragments of cultured specimens (
The noted Δ13CSIMS‐GSMSvalues are most likely due to matrix effects causing sample–standard mismatch for SIMS analyses but may also be a combination of other factors such as SIMS measurement of chemically bound water. The volume of material analyzed via SIMS is ~105times smaller than that analyzed by GSMS; hence, the extent to which these Δ13CSIMS‐GSMSvalues represent differences in analyte or instrument factors remains unclear.
- NSF-PAR ID:
- 10475389
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Rapid Communications in Mass Spectrometry
- Volume:
- 38
- Issue:
- 2
- ISSN:
- 0951-4198
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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