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glycerol dialkyl glycerol tetraether

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Published: 12 October 2023
TABLE 1. RESULTS OF THE BRANCHED GLYCEROL DIALKYL GLYCEROL TETRAETHERS (brGDGTs) DATED CA. 29 MA IN THE YAXICUO FORMATION
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Plots showing relationship of GDGT (glycerol dialkyl glycerol tetraethers) parameters (CBT, cyclization ratio of branched GDGTs, and Ri/b) with pH values in modern Chinese soils and with local mean annual precipitation (MAP). Alkaline soils (pH > 7.5) and enhanced aridity (MAP < 600 mm) can be identified by Ri/b, while CBT index appears unable to distinguish pH variations from 6.5 to 9 and MAP from 300 mm to 1200 mm. Black blocks shown outside cross plots are data corresponding to high alkalinity in Miocene deposits of Zhada section (see text). CBT = –log (Ib + IIb)/(I + II), Ri/b = (IV + IV’ + V + VI + VII + VIII)/(III + IIIb + IIIc + II + IIb + IIc + I + Ib + Ic).
Published: 01 April 2012
Figure 1. Plots showing relationship of GDGT (glycerol dialkyl glycerol tetraethers) parameters (CBT, cyclization ratio of branched GDGTs, and R i/b ) with pH values in modern Chinese soils and with local mean annual precipitation (MAP). Alkaline soils (pH > 7.5) and enhanced aridity (MAP
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Variations of the GDGT (glycerol dialkyl glycerol tetraethers) parameters Ri/b and CBT (cyclization ratio of branched GDGTs) in Zhada section of southwestern Tibetan Plateau indicating presence of highly alkaline deposits and enhanced aridity 9 m.y. ago, associated with shifts in paleoclimate records indicative of contemporaneous monsoon variation. Abundance ratio of Globigerinoides sacculifer and G. ruber from South China Sea (Ocean Drilling Program Site 1146) shows significant intensification of East Asian monsoon at 9–8 m.y. (Zheng et al., 2004). Change in monsoons is proposed to relate to significant and major uplift of Tibetan Plateau 9–8 m.y. ago (An et al., 2001).
Published: 01 April 2012
Figure 2. Variations of the GDGT (glycerol dialkyl glycerol tetraethers) parameters R i/b and CBT (cyclization ratio of branched GDGTs) in Zhada section of southwestern Tibetan Plateau indicating presence of highly alkaline deposits and enhanced aridity 9 m.y. ago, associated with shifts
Journal Article
Journal: Geology
Published: 26 February 2024
Geology (2024) 52 (6): 385–389.
... the last deglaciation based on bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs) analyzed from the sediment sequence of Lake Kielguo, a small volcanic lake in NE China. The results show that summer temperature was lowest during the interval ca. 20–18.2 calibrated (cal.) k.y. B.P...
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Journal Article
Journal: Geology
Published: 01 April 2012
Geology (2012) 40 (4): 291–294.
...Figure 1. Plots showing relationship of GDGT (glycerol dialkyl glycerol tetraethers) parameters (CBT, cyclization ratio of branched GDGTs, and R i/b ) with pH values in modern Chinese soils and with local mean annual precipitation (MAP). Alkaline soils (pH > 7.5) and enhanced aridity (MAP...
FIGURES
Journal Article
Journal: Geology
Published: 01 January 2010
Geology (2010) 38 (1): 7–10.
... of topography. Paleoelevation was determined by reconstructing the change in the hydrogen isotopic composition of precipitation (ΔδD precip ) and mean annual temperature (Δ T GDGT ) (glycerol dialkyl glycerol tetraethers) from the isotopic composition of fossil angiosperm leaf n -alkanes and the distribution...
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Journal Article
Journal: Geology
Published: 02 October 2017
Geology (2017) 45 (11): 1031–1034.
... a fundamental gap in our understanding of Asian climate. Here we reconstruct continental air temperatures for northeast China across the last deglaciation (past 16 k.y.), based on the distribution of bacterial branched glycerol dialkyl glycerol tetraethers in a sequence of the Hani peat (Jilin Province...
FIGURES
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Chemical structural formulas of the nine known branched glycerol dialkyl glycerol tetraethers (brGDGTs).
Published: 01 November 2015
Figure 2. Chemical structural formulas of the nine known branched glycerol dialkyl glycerol tetraethers (brGDGTs).
Journal Article
Journal: GSA Bulletin
Published: 12 October 2023
GSA Bulletin (2024) 136 (5-6): 2359–2372.
...TABLE 1. RESULTS OF THE BRANCHED GLYCEROL DIALKYL GLYCEROL TETRAETHERS (brGDGTs) DATED CA. 29 MA IN THE YAXICUO FORMATION ...
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Journal Article
Journal: PALAIOS
Published: 31 May 2022
PALAIOS (2022) 37 (5): 185–200.
... biomarkers, their stable carbon isotopic compositions, and glycerol dialkyl glycerol tetraethers (GDGTs; at McAbee only). Terpenoids suggest relative trends in gymnosperm abundance between sites that agree with prior macrofossil evidence, though absolute values may overestimate local gymnosperm abundance...
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Series: GSA Special Papers
Published: 07 April 2021
DOI: 10.1130/2020.2548(09)
EISBN: 9780813795485
... to simulate possible glacier length changes through time. Model input paleoclimate values came from branched glycerol dialkyl glycerol tetraether (brGDGT) temperature reconstructions from alpine lakes on Mount Kenya for the last ~31 k.y., and precipitation reconstructions for the LGM came from various East...
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Illustration of biomarker sources, transport, and preservation in aquatic and terrestrial environments. Abbreviations: polycyclic aromatic hydrocarbons (PAHs); glycerol dialkyl glycerol tetraethers (GDGTs).
Published: 01 April 2022
Figure 2. Illustration of biomarker sources, transport, and preservation in aquatic and terrestrial environments. Abbreviations: polycyclic aromatic hydrocarbons (PAHs); glycerol dialkyl glycerol tetraethers (GDGTs).
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Time-paleoelevation plot for the Namling Basin and Gangdese Mountains based on Climate-Leaf Analysis Multivariate Program and stable isotopes. Locations for sites and references see Figure 1. GDGTs—glycerol dialkyl glycerol tetraethers.
Published: 14 February 2022
Figure 8. Time-paleoelevation plot for the Namling Basin and Gangdese Mountains based on Climate-Leaf Analysis Multivariate Program and stable isotopes. Locations for sites and references see Figure 1 . GDGTs—glycerol dialkyl glycerol tetraethers.
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(A) Branched and isoprenoid tetraether (BIT) index, (B) compound-specific carbon (δ13C) stable isotopes, and (C) iGDGT-2/iGDGT-3 ratio in Pollenzo section (after Natalicchio et al., 2019) and Govone section (after Sabino et al., 2021) in the Piedmont Basin. iGDGT—isoprenoid glycerol dialkyl glycerol tetraether; Bp-cren—tricyclic biphytane from crenarchaeol.
Published: 01 January 2022
—isoprenoid glycerol dialkyl glycerol tetraether; Bp-cren—tricyclic biphytane from crenarchaeol.
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Overview of the lipid biosynthetic pathways discussed in the text and key enzymes. Abbreviations: DMAPP = dimethylallyl diphosphate; GGPP = geranylgeranyl diphosphate; GGGP = geranylgeranylglyceryl phosphate synthase; DGGGP = digeranylgeranylglyceryl phosphate synthase, G1P = glycerol 1-phosphate; GDGT = glycerol dialkyl glycerol tetraether; MVA = mevalonate; MEP/DOXP = 2-C-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate; PP = diphosphate
Published: 01 April 2022
-phosphate; GDGT = glycerol dialkyl glycerol tetraether; MVA = mevalonate; MEP/DOXP = 2- C -methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate; PP = diphosphate
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Reconstructed Eocene (52–49 Ma) paleoelevations of Sierra Nevada along line A-A′ using ΔTGDGT (glycerol dialkyl glycerol tetraethers) and ΔδDn-alkane. Errors reflect 2σ uncertainty for modeled ΔδDprecip (precipitation) and ΔT with elevation in modern Sierra range. Dark line represents modern elevations along line A-A′.
Published: 01 January 2010
Figure 4. Reconstructed Eocene (52–49 Ma) paleoelevations of Sierra Nevada along line A-A′ using Δ T GDGT (glycerol dialkyl glycerol tetraethers) and ΔδD n -alkane . Errors reflect 2σ uncertainty for modeled ΔδD precip (precipitation) and Δ T with elevation in modern Sierra range. Dark
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Biomarker data from the Hani peatland, northeast China. (A) Diploptene and C33 n-alkane δ13C (error bars depict standard deviations), where circles reflect individual data points, and thick lines indicate 7-point running averages. (B) Relative abundance of diploptene (crosses reflect individual data points; thick line indicates 7-point running average). (C) IsoGDGT-0 (isoprenoidal glycerol dialkyl glycerol tetraether) accumulation rates (diamonds reflect individual data points; line is 5-point running average) with mean summer insolation at 65°N (dashed line). (D) Archaeol (2,3-diphytanyl-O-sn-glycerol) accumulation rates (squares reflect individual data points; line is 5-point running average); (E) Bacterial branched glycerol dialkyl glycerol tetraether (brGDGT)–based mean annual air temperatures at Hani peatland (northeastern China), with calibration uncertainty (Zheng et al., 2017), together with 14C dates (gray triangles). (F) Atmospheric methane concentrations and δ13Cmethane values obtained from Antarctic ice cores (Möller et al., 2013; Bock et al., 2017). OD—Oldest Dryas; B/A—Bølling-Allerød; YD—Younger Dryas; PB—Preboreal; optimum—Holocene climatic optimum; wrt VPDB—with respect to Vienna Peedee belemnite; EDML—European Project for Ice Coring in Antarctica (EPICA) Dronning Maud Land; TALDICE—Talos Dome Ice Core.
Published: 19 November 2019
reflect individual data points; thick line indicates 7-point running average). (C) IsoGDGT-0 (isoprenoidal glycerol dialkyl glycerol tetraether) accumulation rates (diamonds reflect individual data points; line is 5-point running average) with mean summer insolation at 65°N (dashed line). (D) Archaeol
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Schematic diagram of a bacterial and archaeal cellular membrane showing select lipid modifications encountered in extremophilic microorganisms. Circles signify the type of hydrophilic polar headgroups: phospholipids (oval); glycolipids (round). Ester and ether bonds are marked by a square, locations of modifications in the hydrophobic cores in response to changing environmental conditions are highlighted in bold (see text for details). GDGT = glycerol dialkyl glycerol tetraether.
Published: 01 April 2022
by a square, locations of modifications in the hydrophobic cores in response to changing environmental conditions are highlighted in bold (see text for details). GDGT = glycerol dialkyl glycerol tetraether.
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Detrital zircon ages, volcanic rock ages, gastropods, charophytes, pollen, and ostracod geochronological evidence in the Tuotuohe section, and supporting age evidence. Also shown is the measured magnetostratigraphy of the Tuotuohe section and its correlation with the Geologic Time Scale 2020 (GTS 2020; Gradstein et al., 2020). Biostratigraphic constraints (charophytes, pollen, and ostracod) and detrital zircon ages support the magnetostratigraphic correlation. brGDGTs—branched glycerol dialkyl glycerol tetraethers.
Published: 12 October 2023
2020 (GTS 2020; Gradstein et al., 2020 ). Biostratigraphic constraints (charophytes, pollen, and ostracod) and detrital zircon ages support the magnetostratigraphic correlation. brGDGTs—branched glycerol dialkyl glycerol tetraethers.
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Figure 1. A: High-performance liquid chromatography–mass spectrometry base-peak chromatograms of glycerol dialkyl glycerol tetraether (GDGT) compounds from Lake Michigan, Issyk Kul, Lake Superior, and Lake Malawi. Some compounds are not visible on base-peak chromatogram but were determined via partial ion chromatograms. Peaks relevant to TEX86 (see text) calculation are shaded. B: GDGT structures. GDGT IV′ is stereoisomer of crenarchaeol (GDGT IV).
Published: 01 July 2004
Figure 1. A: High-performance liquid chromatography–mass spectrometry base-peak chromatograms of glycerol dialkyl glycerol tetraether (GDGT) compounds from Lake Michigan, Issyk Kul, Lake Superior, and Lake Malawi. Some compounds are not visible on base-peak chromatogram but were determined via