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Figure 1. Downcore profiles for various bulk and molecular parameters in GGC5, as well as coupled molecular isotope mass-balance solutions (open circles) for fractions of terrestrial (fT), marine (fM), and petrogenic (fP) organic carbon (those in which the surface sediment end-member  13C compositions of Blair et al. [2003] were substituted are given as closed squares; see the Data Repository [see footnote 1]). Depths are relative to the seafloor after accounting for the displacement of 6 cm of surficial sediments during the gravity coring process. Unsupported 210Pbxs activity is shown as closed symbols, 137Cs activity (multiplied by a factor of 10) as open symbols. Colors for even carbon-numbered individual fatty acid homologues (closed symbols) and homologue combinations (open symbols) are as follows: nC18 (blue), nC24 (red), nC26 (orange), nC28 (olive), nC32 (green), nC14–20 (blue), nC24–32 (red), and nC30–32 (green). Colors for alkane combinations (all open symbols) are as follows: even-numbered homologues nC16–20 (blue) and nC24–32 (red), and odd-numbered homologues nC25–33 (green). Analytical uncertainties are not shown for clarity, except for mass-balance results where they integrate the 1 deviation in solutions across 7 –9 13Cbiomass – 13Clipid offset for terrestrial and marine end members and 0–2 offset for petrogenic material. Profiles for K/Ti and Si/Ti are shown as 10 point running averages. TOC—total organic carbon; TN—total nitrogen. Positive X-ray radiograph of GGC5 is shown above the plot; light regions reflect clay-rich deposits. Gray bars denote flood layers (see text for assignment criteria); historical (calendar) emplacement dates are given at bottom.
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