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[1] Here we report 420 kyr long records of sediment geochemical and color variations from the southwestern Iberian Margin. We synchronized the Iberian Margin sediment record to Antarctic ice cores and speleothem records on millennial time scales and investigated the phase responses relative to orbital forcing of multiple proxy records available from these cores. Iberian Margin sediments contain strong precession power. Sediment "redness" (a* and 570-560 nm) and the ratio of long-chain alcohols to n-alkanes (C 26 OH/(C 26 OH + C 29 )) are highly coherent and in-phase with precession. Redder layers and more oxidizing conditions (low alcohol ratio) occur near precession minima (summer insolation maxima). We suggest these proxies respond rapidly to low-latitude insolation forcing by wind-driven processes (e.g., dust transport, upwelling, precipitation). Most Iberian Margin sediment parameters lag obliquity maxima by 7-8 ka, indicating a consistent linear response to insolation forcing at obliquity frequencies driven mainly by high-latitude processes. Although the lengths of the time series are short (420 ka) for detecting 100 kyr eccentricity cycles, the phase relationships support those obtained by Shackleton [2000]. Antarctic temperature and the Iberian Margin alcohol ratios (C 26 OH/ (C 26 OH + C 29 )) lead eccentricity maxima by 6 kyr, with lower ratios (increased oxygenation) occurring at eccentricity maxima. CO 2 , CH 4 , and Iberian SST are nearly in phase with eccentricity, and minimum ice volume (as inferred from Pacific d 18 O seawater ) lags eccentricity maxima by 10 kyr. The phase relationships derived in this study continue to support a potential role of the Earth's carbon cycle in contributing to the 100 kyr cycle.

[1] Detailed mapping, sampling, and geochemical analyses of lava flows erupted from an ∼18 km long section of the northern East Pacific Rise (EPR) from 9°46′N to 9°56′N during 2005-2006 provide unique data pertaining to the short-term thermochemical changes in a mid-ocean ridge magmatic system. mantle source over the spatial extent of the eruption and petrogenetic processes (e.g., fractional crystallization and magma mixing) operating within the crystal mush zone and axial magma chamber (AMC) before and during the 13 year repose period. Geochemical modeling suggests that the 2005-2006 lavas represent differentiated residual liquids from the 1991-1992 eruption that were modified by melts added from deeper within the crust and that the eruption was not initiated by the injection of hotter, more primitive basalt directly into the AMC. Rather, the eruption was driven by AMC pressurization from persistent or episodic addition of more evolved magma from the crystal mush zone into the overlying subridge AMC during the period between the two eruptions. Heat balance calculations of a hydrothermally cooled AMC support this model and show that continual addition of melt from the mush zone was required to maintain a sizable AMC over this time interval.

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We report the use of direct (hetero)arylation polymerizations (DHAP) as a means of obtaining 3,4-propylenedioxythiophenebased conjugated polymers for use in electrochromics. This method offers a rapid route to achieving polymers in high yields with simplified purification procedures and low residual metal content, as determined by inductive coupled plasma-mass spectrometry (ICP-MS). The studied polymers possess comparable electrochromic properties to those previously reported by our group, implying that their switching ability from a colored to a transmissive state is independent of the residual metallic impurities.