TY - JOUR
T1 - 10Be variation in surficial sediments of the Central Indian Basin
AU - Nagender Nath, B.
AU - Aldahan, A.
AU - Possnert, G.
AU - Selvaraj, K.
AU - Mascarenhas-Pereira, M. B.L.
AU - Chen, C. T.A.
N1 - Funding Information:
Ship crew, officers of R.V.A.A. Sidorenko and scientific participants from NIO are thanked for their support while the sediments were collected. Ship time was supported by Department of Ocean Development, Government of India for undertaking environmental impact assessment of offshore mining. Most of the laboratory work to generate the data presented here was carried out in Uppsala University during the stay of first author (B.N.), when he was a Sir C.V. Raman Research fellow. CSIR, Government of India is thanked for supporting this stay. First author (B.N.) would like to express his thanks to Ms. Inger Pahlsson at Uppsala University and M/s. Naman, Nivedita, Vitya at NIO for their laboratory help. K.S. thanks National Science Council of Taiwan (NSC-94-2621-Z-110-001 and 94-2611-M110-001) for his postdoctoral fellowship NIO Contribution No. 4231. This research is partially supported by a grant to CTA Chen (NSC 95-2621-Z-110-005) from the National Science Council of Taiwan.
PY - 2007/6
Y1 - 2007/6
N2 - Distribution of 10Be in systematically collected (degree × degree interval at 10 to 16 °S; 73.5 to 76.5 °E) surficial siliceous ooze, siliceous clay and pelagic clay sediments (top 2 cm) from the abyssal Central Indian Basin and the Andaman Sea is used to evaluate sources and to decipher the transport pathways of sediment particles, demarcate sediment depocenters and erosional areas. While 10Be concentrations display a wide variation (0.12-5.56 × 109 atoms g-1) with an average of 3.58 × 109 atoms g-1 in the Central Indian Basin, the values in the Andaman Sea are uniform with an average of 1.49 × 109 atoms g-1. The 10Be/9Be values in the Central Indian Basin sediments range between 0.06 and 2.99 × 10-8 atoms atoms-1 and average to ∼1.56 × 10-8 atoms atoms-1. Correlation of 10Be data with some selected major (Al, Mn, Ti) and trace (Rb and Ba) elements suggest that large part of the isotope has been supplied through direct atmospheric fallout from the water column and minor part from lithogenic detrital flux. Significantly lower 10Be accumulation rates in the Central Indian Basin and an order of magnitude higher in the Andaman Sea sediments compared to the estimated global average production rates indicate removal of the isotopes at the continental margins. Bottom topography seems to exert control on local 10Be variation, where sediments deposited in valleys or topographic depressions contain higher 10Be concentrations in contrast to the probably erosion-dominated areas at the slopes and troughs.
AB - Distribution of 10Be in systematically collected (degree × degree interval at 10 to 16 °S; 73.5 to 76.5 °E) surficial siliceous ooze, siliceous clay and pelagic clay sediments (top 2 cm) from the abyssal Central Indian Basin and the Andaman Sea is used to evaluate sources and to decipher the transport pathways of sediment particles, demarcate sediment depocenters and erosional areas. While 10Be concentrations display a wide variation (0.12-5.56 × 109 atoms g-1) with an average of 3.58 × 109 atoms g-1 in the Central Indian Basin, the values in the Andaman Sea are uniform with an average of 1.49 × 109 atoms g-1. The 10Be/9Be values in the Central Indian Basin sediments range between 0.06 and 2.99 × 10-8 atoms atoms-1 and average to ∼1.56 × 10-8 atoms atoms-1. Correlation of 10Be data with some selected major (Al, Mn, Ti) and trace (Rb and Ba) elements suggest that large part of the isotope has been supplied through direct atmospheric fallout from the water column and minor part from lithogenic detrital flux. Significantly lower 10Be accumulation rates in the Central Indian Basin and an order of magnitude higher in the Andaman Sea sediments compared to the estimated global average production rates indicate removal of the isotopes at the continental margins. Bottom topography seems to exert control on local 10Be variation, where sediments deposited in valleys or topographic depressions contain higher 10Be concentrations in contrast to the probably erosion-dominated areas at the slopes and troughs.
KW - Andaman Sea
KW - Beryllium isotopes
KW - Central Indian Basin
KW - Geochemistry
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U2 - 10.1016/j.nimb.2007.01.293
DO - 10.1016/j.nimb.2007.01.293
M3 - Article
AN - SCOPUS:34248149313
SN - 0168-583X
VL - 259
SP - 610
EP - 615
JO - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
JF - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
IS - 1
ER -