Matches in SemOpenAlex for { <https://semopenalex.org/work/W1539254711> ?p ?o ?g. }
- W1539254711 abstract "Determination of past sea surface temperature (SST) is of primary importance for the reconstruction of natural climatic changes, modelling of climate and reconstruction of ocean circulation. Recently, a new SST proxy was introduced, the TetraEther indeX of lipids with 86 carbons (TEX86), which is based on temperature-related changes that occur in the composition of creanarchaeotal membrane lipids. An empirical correlation between TEX86 values of sediment core tops from a wide variety of geographical locations and annual mean SST has been used to calibrate the TEX86 proxy. The main objective of the work described in this thesis was to improve, validate and apply the TEX86 proxy. To do this we focused on a) the analytical aspects of the TEX86, b) the transport of GDGTs to the sediment and the influence of diagenesis and c) the application of the proxy in various settings. Regarding the analytical aspects, the detection limit of the GDGTs was established at 0.05 ng GDGTs injected on-column. Furthermore application of SIM improved the analytical reproducibility to 0.3C, and a new synthetic internal GDGT standard was used which improved the accuracy of GDGT abundance measurements increasing the potential of GDGTs in (paleo)ecological studies substantially. The transport and diagenesis of GDGTs were also subject of study as they are essential in understanding and applying the TEX86 as palaeothermometer. This study revealed the presence of GDGTs in both stomachs and, in lower amounts, in the intestines showing uptake of GDGTs by decapods, but TEX86-derived temperatures are not significantly different between stomachs and intestines (1C), suggesting that TEX86 values are not altered during gut transit. To investigate the effect of degradation by long term exposure to oxygen we analyzed GDGTs abundance, TEX86 and Branched versus Isoprenoid Tetraether index (BIT) in several Madeira Abyssal Plain turbidites across an oxidation front. A decrease by several orders of magnitude in the concentrations of GDGTs was found and also substantial shifts in the BIT and TEX86. The shifts are interpreted to be caused by a strong relative increase in soil-derived GDGTs relative to the marine-derived GDGTs. This selective preservation of soil-derived lipids which are chemically nearly identical to that of their marine counterpart strongly suggests that the mineral matrix to which soil organic matter is attached enhanced its preservation. Finally the application of the TEX86 to a range of environments and time resolutions in combination with other SST proxies allowed the validation of the TEX86 proxy as a paleothermometer. While in most studies TEX86 showed a good correlation with SST, work using sediment traps and a sediment core covering the last 150 years in the Santa Barbara Basin revealed that TEX86 values were always substantially lower than sea surface temperatures (SST), indicating a sub-surface origin, likely between 100-150 m. This result highlights the importance of performing calibration studies using sediment traps and core tops before applying the TEX86 temperature proxy in a given study area." @default.
- W1539254711 created "2016-06-24" @default.
- W1539254711 creator A5048724229 @default.
- W1539254711 date "2007-09-17" @default.
- W1539254711 modified "2023-09-23" @default.
- W1539254711 title "TEX86 paleothermometry: proxy validation and application in marine sediments" @default.
- W1539254711 cites W1489155911 @default.
- W1539254711 cites W1531284530 @default.
- W1539254711 cites W1548291402 @default.
- W1539254711 cites W1580206559 @default.
- W1539254711 cites W1596192798 @default.
- W1539254711 cites W1645042569 @default.
- W1539254711 cites W1721554464 @default.
- W1539254711 cites W1935412559 @default.
- W1539254711 cites W1937838860 @default.
- W1539254711 cites W1966642060 @default.
- W1539254711 cites W196847660 @default.
- W1539254711 cites W1968721411 @default.
- W1539254711 cites W1971890404 @default.
- W1539254711 cites W1980094787 @default.
- W1539254711 cites W1984962510 @default.
- W1539254711 cites W1985524448 @default.
- W1539254711 cites W1985698232 @default.
- W1539254711 cites W1995741948 @default.
- W1539254711 cites W1999369622 @default.
- W1539254711 cites W2001165539 @default.
- W1539254711 cites W2001400767 @default.
- W1539254711 cites W2003073603 @default.
- W1539254711 cites W2005832186 @default.
- W1539254711 cites W2008019457 @default.
- W1539254711 cites W2008875043 @default.
- W1539254711 cites W2016417226 @default.
- W1539254711 cites W2017360304 @default.
- W1539254711 cites W2020477897 @default.
- W1539254711 cites W2031512204 @default.
- W1539254711 cites W2031715652 @default.
- W1539254711 cites W2035891155 @default.
- W1539254711 cites W2038281478 @default.
- W1539254711 cites W2042852481 @default.
- W1539254711 cites W2042895971 @default.
- W1539254711 cites W2049712313 @default.
- W1539254711 cites W2051973454 @default.
- W1539254711 cites W2052584778 @default.
- W1539254711 cites W2058653258 @default.
- W1539254711 cites W2059206728 @default.
- W1539254711 cites W2059556264 @default.
- W1539254711 cites W2061761033 @default.
- W1539254711 cites W2065781072 @default.
- W1539254711 cites W2065839082 @default.
- W1539254711 cites W2066948603 @default.
- W1539254711 cites W2087609799 @default.
- W1539254711 cites W2089526135 @default.
- W1539254711 cites W2091284813 @default.
- W1539254711 cites W2092811721 @default.
- W1539254711 cites W2093401535 @default.
- W1539254711 cites W2093425893 @default.
- W1539254711 cites W2099221882 @default.
- W1539254711 cites W2104208100 @default.
- W1539254711 cites W2105346402 @default.
- W1539254711 cites W2107381074 @default.
- W1539254711 cites W2111984792 @default.
- W1539254711 cites W2113387025 @default.
- W1539254711 cites W2115338073 @default.
- W1539254711 cites W2116643982 @default.
- W1539254711 cites W2118063643 @default.
- W1539254711 cites W2119689998 @default.
- W1539254711 cites W2120537950 @default.
- W1539254711 cites W2120560331 @default.
- W1539254711 cites W2124143154 @default.
- W1539254711 cites W2125357919 @default.
- W1539254711 cites W2127380962 @default.
- W1539254711 cites W2135057795 @default.
- W1539254711 cites W2137446485 @default.
- W1539254711 cites W2137582471 @default.
- W1539254711 cites W2138169388 @default.
- W1539254711 cites W2138717680 @default.
- W1539254711 cites W2146195962 @default.
- W1539254711 cites W2146605432 @default.
- W1539254711 cites W2146866283 @default.
- W1539254711 cites W2149255324 @default.
- W1539254711 cites W2151186829 @default.
- W1539254711 cites W2158989204 @default.
- W1539254711 cites W2166324565 @default.
- W1539254711 cites W2166543383 @default.
- W1539254711 cites W2166865790 @default.
- W1539254711 cites W2169409681 @default.
- W1539254711 cites W2171640258 @default.
- W1539254711 cites W2176670204 @default.
- W1539254711 cites W626657818 @default.
- W1539254711 hasPublicationYear "2007" @default.
- W1539254711 type Work @default.
- W1539254711 sameAs 1539254711 @default.
- W1539254711 citedByCount "0" @default.
- W1539254711 crossrefType "dissertation" @default.
- W1539254711 hasAuthorship W1539254711A5048724229 @default.
- W1539254711 hasConcept C111368507 @default.
- W1539254711 hasConcept C114793014 @default.
- W1539254711 hasConcept C11864286 @default.
- W1539254711 hasConcept C119857082 @default.
- W1539254711 hasConcept C127313418 @default.