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Table 1 Concentrations, δ13C values, and typical indices based on n-alkanes in the subsamples with different sediment depth of core R23. The relative contribution of long chain n-alkanes from C3 and C4 plants are calculated by carbon isotopes of the C31 n-alkane

From: A potential suite of climate markers of long-chain n-alkanes and alkenones preserved in the top sediments from the Pacific sector of the Southern Ocean

Depth
(cm)
δ13C23
(‰)
δ13C24
(‰)
δ13C25
(‰)
δ13C26
(‰)
δ13C27
(‰)
δ13C28
(‰)
δ13C29
(‰)
δ13C31
(‰)
n-alkanesa
(ng/g)
C4
(%)
C3
(%)
ACLb CPIc
16 29.6 28.8 29.9 33.2 28.5 32.2 27.4 28.3 445 55 45 30.1 1.6
88 29.5 31.8 27.3 30.0 26.3 33.1 25.1 25.5 328 75 25 30.3 2.0
166 25.4 26.4 26.7 32.5 28.3 38.0 27.1 27.8 295 59 41 30.1 2.1
243 27.1 26.8 26.8 30.4 26.7 33.3 29.8 28.3 362 55 45 30.3 2.5
323 29.8 31.2 30.6 35.0 28.3 32.1 29.4 27.9 324 58 42 29.3 1.3
398 31.5 35.9 30.0 36.7 28.6 34.6 25.0 24.8 787 80 20 29.6 1.3
482 26.8 28.4 29.3 30.3 26.8 30.1 27.4 26.6 411 67 33 30.7 1.9
550 27.1 30.7 29.3 35.1 27.8 31.2 27.8 25.4 420 76 24 30.1 1.6
626 30.4 32.2 31.7 34.6 29.6 30.9 26.4 25.8 344 73 27 29.6 1.6
698 28.6 30.6 29.0 32.7 27.8 31.8 27.0 25.8 490 73 27 29.3 1.1
762 28.8 29.3 30.0 35.3 26.7 32.1 30.4 29.4 455 47 53 29.8 1.6
818 28.8 28.7 32.3 37.4 30.1 35.8 27.7 27.2 503 63 37 30.1 1.7
  1. aTotal concentrations of C23-C35 n-alkanes
  2. bACL27-35 =∑(i × Xi)/∑Xi, where X is abundance and i ranges from C27 to C35 odd n-alkanes
  3. cCPI27-33 = 0.5 × ∑(C27C33)/(C26C32) + 0.5 × ∑(C27C33)/(C28C34)