Identification

Title

Stable isotope and trace element data for planktonic foraminifera from IODP Site U1338 (NERC Grant NE/I528750/1)

Abstract

Oxygen and carbon isotope ratios (δ18O, δ13C) were measured on 10 to 12 shells of mixed-layer dwelling species Globigerinoides subquadratus from the 250 to 315 μm size fraction from 425 meters composite depth (mcd) until its extinction at 390 mcd. Analyses then continue with Globigerinoides spp. until 350 mcd. In a few samples, where foraminiferal density was low, only 5–7 specimens were analyzed. Analyses were made with a VG Optima mass spectrometer with multi prep device at the British Geological Survey, Keyworth, UK. When picking shells, care was taken to exclude individuals with broken or missing chambers, although preservation of specimens was generally excellent (Fox & Wade, 2013). The external reproducibility of our measurements is ±0.07‰ and ±0.05‰ for δ18O and δ13C respectively. To examine the reproducibility of the results, duplicate measurements were made on 35 samples (5%), which indicate mean reproducibility better than ±0.12‰ and ±0.14‰ for δ18O and δ13C, respectively. Oxygen isotope data are reported as per mil on the VPDB scale (Table S1) calibrated through laboratory and international standards. At ODP Site 1146, δ18O and δ13C were measured by Holbourn et al., (2010) on the mixed-layer dwelling planktonic foraminifera Globigerinoides obliquus or Gs. subquadratus, using 10 to 20 well-preserved tests from the size fraction 250-350 μm. Paired measurements in 51 samples indicate no significant offset in δ18O and δ13C between Gs. obliquus and Gs. subquadratus. Detailed methods are outlined in Holbourn et al., (2010). δ13C data are not used here. For Mg/Ca analyses, we selected 25–35 specimens of Trilobatus quadrilobatus (140–550 μg) from the 250 to 315 μm size fraction; the same size fraction as used for δ18O analysis, to minimize size-related intraspecific elemental variation (Elderfield et al., 2002). Analyses were performed on 86 samples over the studied interval. The tests were gently crushed and subsequently cleaned according to the protocol of Martin & Lea (2002) to remove clays. Cleaning included a reductive step with hydrazine to remove Mn-(hydr)oxides. Samples were measured on an ICP-AES device at Christian-Albrechts-Universität zu Kiel, Germany. Analytical precision is ~1.1%, based on measurements of an internal laboratory standard. Replicate Mg/Ca measurements revealed an average standard deviation of ~0.08 mmol/mol. Adequate cleaning is indicated by very low Fe/Ca, Al/Ca and Mn/Ca ratios.

Resource type

dataset

Resource locator

https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item164526

name: Data

function: download

Unique resource identifier

code

http://data.bgs.ac.uk/id/dataHolding/13607738

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

Benthonic foraminifera

Planktonic foraminifera

Stable isotopes

Trace metals

NGDC Deposited Data

originating controlled vocabulary

title

reference date

date type

revision

effective date

2022

Keyword set

keyword value

Keyword set

keyword value

NERC_DDC

Geographic location

West bounding longitude

-117.9600

East bounding longitude

-117.9600

North bounding latitude

2.5000

South bounding latitude

2.5000

Extent

Extent group

authority code

title

reference date

date type

revision

effective date

2010

code identifying the extent

NORTH PACIFIC OCEAN [id=2002268]

Temporal reference

Temporal extent

Begin position

2011-10-03

End position

2014-09-08

Dataset reference date

date type

creation

effective date

2021-04-14

Frequency of update

notApplicable

Quality and validity

Lineage

Methodology is described in detail in Fox et al., 2021. Temperature gradients across the Pacific Ocean during the middle Miocene. (In Review)

Conformity

Conformity report

specification

title

reference date

date type

publication

effective date

2011

degree

false

explanation

See the referenced specification

Conformity report

specification

title

reference date

date type

publication

effective date

2010-12-08

degree

false

explanation

See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Data format

name of format

csv

version of format

Constraints related to access and use

Constraint set

Limitations on public access

Constraint set

Limitations on public access

The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Responsible organisations

Responsible party

organisation name

Kingston University

email address

not available

responsible party role

originator

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

British Geological Survey

full postal address

Environmental Science Centre,Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

+44 115 936 3100

email address

enquiries@bgs.ac.uk

responsible party role

pointOfContact

Metadata date

2025-03-24

Metadata language