Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions
An empirical dissolution index for planktonic foraminifera, XDX, was established based on the appearance of tests in computed tomography (CT) scans (Chapter 4). Calibrations between XDX and Delta[CO32-], Delta-mass (mass lost to dissolution) and Delta Mg/Ca (reduction in Mg/Ca due to dissolution) al...
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Universität Bremen
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ftsubbremen:oai:media.suub.uni-bremen.de:Publications/elib/57 2023-05-15T18:00:27+02:00 Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions Untersuchungen zur Lösung planktonischer Foraminiferenschalen mittels Computertomographie (CT): eine Möglichkeit zur Verbesserung paläozeanographischer Rekonstruktionen Johnstone, Heather Schulz, Michael Wefer, Gerold 2010-11-15 application/pdf https://media.suub.uni-bremen.de/handle/elib/57 https://nbn-resolving.org/urn:nbn:de:gbv:46-00101815-15 eng eng Universität Bremen FB5 Geowissenschaften https://media.suub.uni-bremen.de/handle/elib/57 urn:nbn:de:gbv:46-00101815-15 info:eu-repo/semantics/openAccess Bitte wählen Sie eine Lizenz aus: (Unsere Empfehlung: CC-BY) CC-BY planktonic foraminifera dissolution Mg/Ca SST Indian Ocean XDX reductive cleaning computed tomography CT 550 550 Earth sciences and geology ddc:550 Dissertation doctoralThesis 2010 ftsubbremen 2022-11-09T07:09:17Z An empirical dissolution index for planktonic foraminifera, XDX, was established based on the appearance of tests in computed tomography (CT) scans (Chapter 4). Calibrations between XDX and Delta[CO32-], Delta-mass (mass lost to dissolution) and Delta Mg/Ca (reduction in Mg/Ca due to dissolution) allow estimates of deep ocean Delta[CO32-] and also dissolution-corrected test mass and Mg/Ca (Chapter 5). Delta[CO32-] reconstructed for the deep (4,157 m) tropical western Indian Ocean (WIND28K) increased by ~25 µmol/kg over Termination I and ~15 µmol/kg over Termination II while dissolution maxima coincided with transitions to colder stages (Chapter 6). XDX-corrected Mg/Ca-derived SSTs were coolest during MIS 3. Minimum test mass in the corrected record coincided with the lowest temperatures. Comparison of two methods of cleaning foraminiferal tests from a depth transect (Chapter 7) found no offset in Mg/Ca between methods for G. sacculifer and P. obliquiloculata. Mg/Ca was decreased by reductive cleaning by ~4% for G. ruber and ~10% for N. dutertrei. Offset in Mg/Ca between the two methods was insensitive to preservation state. Doctoral or Postdoctoral Thesis Planktonic foraminifera Media SuUB Bremen (Staats- und Universitätsbibliothek Bremen) Indian |
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Open Polar |
collection |
Media SuUB Bremen (Staats- und Universitätsbibliothek Bremen) |
op_collection_id |
ftsubbremen |
language |
English |
topic |
planktonic foraminifera dissolution Mg/Ca SST Indian Ocean XDX reductive cleaning computed tomography CT 550 550 Earth sciences and geology ddc:550 |
spellingShingle |
planktonic foraminifera dissolution Mg/Ca SST Indian Ocean XDX reductive cleaning computed tomography CT 550 550 Earth sciences and geology ddc:550 Johnstone, Heather Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
topic_facet |
planktonic foraminifera dissolution Mg/Ca SST Indian Ocean XDX reductive cleaning computed tomography CT 550 550 Earth sciences and geology ddc:550 |
description |
An empirical dissolution index for planktonic foraminifera, XDX, was established based on the appearance of tests in computed tomography (CT) scans (Chapter 4). Calibrations between XDX and Delta[CO32-], Delta-mass (mass lost to dissolution) and Delta Mg/Ca (reduction in Mg/Ca due to dissolution) allow estimates of deep ocean Delta[CO32-] and also dissolution-corrected test mass and Mg/Ca (Chapter 5). Delta[CO32-] reconstructed for the deep (4,157 m) tropical western Indian Ocean (WIND28K) increased by ~25 µmol/kg over Termination I and ~15 µmol/kg over Termination II while dissolution maxima coincided with transitions to colder stages (Chapter 6). XDX-corrected Mg/Ca-derived SSTs were coolest during MIS 3. Minimum test mass in the corrected record coincided with the lowest temperatures. Comparison of two methods of cleaning foraminiferal tests from a depth transect (Chapter 7) found no offset in Mg/Ca between methods for G. sacculifer and P. obliquiloculata. Mg/Ca was decreased by reductive cleaning by ~4% for G. ruber and ~10% for N. dutertrei. Offset in Mg/Ca between the two methods was insensitive to preservation state. |
author2 |
Schulz, Michael Wefer, Gerold |
format |
Doctoral or Postdoctoral Thesis |
author |
Johnstone, Heather |
author_facet |
Johnstone, Heather |
author_sort |
Johnstone, Heather |
title |
Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
title_short |
Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
title_full |
Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
title_fullStr |
Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
title_full_unstemmed |
Assessing dissolution in the tests of planktonic foraminifera using computed tomography (CT): potential for improving paleoceanographic reconstructions |
title_sort |
assessing dissolution in the tests of planktonic foraminifera using computed tomography (ct): potential for improving paleoceanographic reconstructions |
publisher |
Universität Bremen |
publishDate |
2010 |
url |
https://media.suub.uni-bremen.de/handle/elib/57 https://nbn-resolving.org/urn:nbn:de:gbv:46-00101815-15 |
geographic |
Indian |
geographic_facet |
Indian |
genre |
Planktonic foraminifera |
genre_facet |
Planktonic foraminifera |
op_relation |
https://media.suub.uni-bremen.de/handle/elib/57 urn:nbn:de:gbv:46-00101815-15 |
op_rights |
info:eu-repo/semantics/openAccess Bitte wählen Sie eine Lizenz aus: (Unsere Empfehlung: CC-BY) |
op_rightsnorm |
CC-BY |
_version_ |
1766169554737692672 |