Open AccessIntratest Variations in Trace Element Composition of Amphistegina lessonii Using Femtosecond‐Laser Ablation‐ICP‐Mass Spectrometry: A Field Study From Akajima, Okinawa Prefecture, Japan
Author(s) -
Khanolkar Sonal,
Schiebel Ralf,
Singh Asmita,
Saraswati Pratul Kumar,
Jochum Klaus Peter,
Weis Ulrike,
Stoll Brigitte,
Haug Gerald H.
Publication year - 2021
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2020gc009443
Subject(s) - oceanography , geology , reef , coral reef , benthic zone , trace element , foraminifera , inductively coupled plasma mass spectrometry , mass spectrometry , geochemistry , chemistry , chromatography
Amphistegina are common larger benthic foraminifer in coral reefs, with a nearly circumtropical distribution, and are major contributors to the CaCO 3 budget of shallow marine environments. The family Amphisteginidae is dominant in Cenozoic carbonates. However, its potential as a proxy for paleoclimate reconstruction has not been completely explored. The intratest variability in trace elements of Amphistegina lessonii has been investigated using femtosecond‐laser ablation‐inductively coupled plasma‐mass spectrometry (fs‐LA‐ICP‐MS). We collected and analyzed adult specimens of A. lessonii in September 2003, November 2003, January 2004, and March 2004, from ∼2 m water depth in the coral reefs of Akajima, Okinawa, Japan. Tests of A. lessonii from these four collections were analyzed for Mg/Ca of the septa to observe Test Size‐Lifespan relationships. The lifespan of a specimen of A. lessonii of 1,200 µm in diameter is estimated at ∼3 and ∼2 months for specimens 900 µm in size. Over the estimated lifespans, Mg/Ca of individual specimens of A. lessonii is highly variable and displays co‐variation with temperature and tidal heights. Future projects may apply and further test this approach for the reconstruction of the tropical shallow marine paleoenvironments.