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norcholestane

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Journal Article
Journal: Geology
Published: 01 September 1998
Geology (1998) 26 (9): 783–786.
.... We demonstrate here that 24-norcholestane biomarkers, i.e., C26 steranes (saturated hydrocarbons having a steroid skeleton), can be useful to constrain the age and paleolatitude of geologic samples. The biological precursors of 24-norcholestanes remain unclear, but samples from more than 100 basins...
Journal Article
Journal: Geology
Published: 01 May 2007
Geology (2007) 35 (5): 419–422.
...Sebastiaan W. Rampen; Stefan Schouten; Ben Abbas; F. Elda Panoto; Gerard Muyzer; Christine N. Campbell; Johanna Fehling; Jaap S. Sinninghe Damsté Abstract 24-norcholestanes have been shown to be useful biomarkers to assess the age of sediments and petroleum, but until now, the biological sources...
FIGURES
Image
Cross-plot showing the norcholestane ratio (NCR) against the nordiacholestane ratio (NDR). Age classification was carried out according to Holba et al. (1998a, b).
Published: 07 October 2016
Fig. 6. Cross-plot showing the norcholestane ratio (NCR) against the nordiacholestane ratio (NDR). Age classification was carried out according to Holba et al . (1998 a , b ).
Image
Assessment of source age applying norcholestane (NCR) and nordiacholestane ratios (NDR) according to Holba et al. (1998a, b). The NCR values indicate mostly Cretaceous ages, and Tertiary age is suggested for sample 120.611. The NDR suggests Cretaceous and Upper Jurassic ages with sample NZS-255 being on the border to late Paleogene age.
Published: 01 June 2010
Figure 16 Assessment of source age applying norcholestane (NCR) and nordiacholestane ratios (NDR) according to Holba et al. (1998a , b ). The NCR values indicate mostly Cretaceous ages, and Tertiary age is suggested for sample 120.611. The NDR suggests Cretaceous and Upper Jurassic ages
Image
Figure 1. Comparison of the 24-norcholestane ratio with the diversity of dinoflagellates and diatoms over geologic time. The shaded area (a) is the typical range of 24-norcholestane concentration for petroleum with age from Holba et al. (1998b). The solid line (b) shows the number of described dinoflagellate species (Tappan and Loeblich, 1973), and the dashed line (c) shows the number of described centric diatom species (Tappan and Loeblich, 1973). At present, >10,000 diatom species (Mann, 1999) and ∼2000 dinoflagellate species (Taylor, 1987) exist.
Published: 01 May 2007
Figure 1. Comparison of the 24-norcholestane ratio with the diversity of dinoflagellates and diatoms over geologic time. The shaded area (a) is the typical range of 24-norcholestane concentration for petroleum with age from Holba et al. (1998b) . The solid line (b) shows the number of described
Image
Comparative diagram showing (A) 24-norcholestane (NCR) vs. geologic age with white field indicating the variation of NCR with geologic age (modified from Holba et al., 1998a, b). (B) δ13C variation through geologic time with fields being defined by diagonal lines (modified from Chung et al., 1992), and different average values represented by solid line with dots, from Andrusevich et al., (1998). For both figures the stars indicate average values.
Published: 01 November 2005
Figure 12 Comparative diagram showing (A) 24-norcholestane (NCR) vs. geologic age with white field indicating the variation of NCR with geologic age (modified from Holba et al., 1998a , b ). (B) δ 13 C variation through geologic time with fields being defined by diagonal lines (modified from
Journal Article
Journal: AAPG Bulletin
Published: 01 November 2005
AAPG Bulletin (2005) 89 (11): 1519–1545.
...Figure 12 Comparative diagram showing (A) 24-norcholestane (NCR) vs. geologic age with white field indicating the variation of NCR with geologic age (modified from Holba et al., 1998a , b ). (B) δ 13 C variation through geologic time with fields being defined by diagonal lines (modified from...
FIGURES | View All (14)
Image
—Representative metastable reaction monitoring m/z 358 to 217 mass chromatogram for hypersaline lacustrine oils indicates high 24-norcholestane ratios (inset table).
Published: 11 December 1999
Figure 11 —Representative metastable reaction monitoring m/z 358 to 217 mass chromatogram for hypersaline lacustrine oils indicates high 24-norcholestane ratios (inset table).
Journal Article
Journal: Geology
Published: 01 March 2000
Geology (2000) 28 (3): 251–254.
... marine or coal-forming depositional environments. A TPP ratio, constructed from the gas chromatography–tandem mass spectrometry peak areas of a C 30 tetracyclic polyprenoid divided by the sum of the peak areas of the C 26 27-norcholestanes, revealed great specificity in identifying freshwater or brackish...
FIGURES
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Figure 1. Gas chromatography–tandem mass spectrometry (GC/MS/MS) mass chromatograms. A: 414→259 lacustrine source-rock extract from Triassic Cacheuta Shale, Cuyo basin, Argentina. B: 414→259 from Jurassic marine oil, Ekofisk field, North Sea, Norway. C: 358→217 norcholestanes from Jurassic marine oil, Cook Inlet, Alaska. Inset shows structure for compound 1. Peaks a and b = 21R and 21S isomers of tetracyclic polyprenoids (TPP) (1), c = 20S,α,α,α-3β-propylcholestane, d = 20R,α,β,β-3β-propylcholestane, e = 20S,α,β,β-3β-propylcholestane, f = 20R, α,α,α-3β-propylcholestane, g = 27-nordiacholestane isomers of compound 2, h = 27-norcholestane isomers of compound 3 (see Holba et al., 1998).
Published: 01 March 2000
Figure 1. Gas chromatography–tandem mass spectrometry (GC/MS/MS) mass chromatograms. A: 414 → 259 lacustrine source-rock extract from Triassic Cacheuta Shale, Cuyo basin, Argentina. B: 414 → 259 from Jurassic marine oil, Ekofisk field, North Sea, Norway. C: 358 → 217 norcholestanes from
Image
The m/z 358 → m/z 217 parent-daughter mass chromatograms of two samples from Matochkin Strait with norcholestane (NCR) and nordiacholestane (NDR) values (Table 6). Peak identifications are from Holba et al. (1998a).
Published: 01 June 2010
Figure 15 The m / z 358 → m / z 217 parent-daughter mass chromatograms of two samples from Matochkin Strait with norcholestane (NCR) and nordiacholestane (NDR) values ( Table 6 ). Peak identifications are from Holba et al. (1998a) .
Series: AAPG Memoir
Publisher: The American Association of Petroleum Geologists and Brazilpetrostudies
Published: 01 January 2021
DOI: 10.1306/13722315MSB.3.1853
EISBN: 9781629812892
... analysis are definitive for making those distinctions, including, for example, 24- n -propylcholestanes (marine algal steranes), dinosteranes concentrations (dinoflagellate steranes), and other A-ring methyl steranes and 24-norcholestanes (putatively diatom related). One of the highly cracked post-salt...
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MRM chromatograms (M+ ⟶ m/z 217) showing the C21-C29 sterane distributions for the silicilyte, shale and carbonate (population A and B) C14+ saturate extracts from southern Oman plays. The sterane distributions (carbon number and relative intensity shown) show overall a C29 sterane predominance. 21-norcholestane is only detected in silicilyte samples.
Published: 01 October 2009
predominance. 21-norcholestane is only detected in silicilyte samples.
Journal Article
Journal: AAPG Bulletin
Published: 01 June 2010
AAPG Bulletin (2010) 94 (6): 791–817.
...Figure 16 Assessment of source age applying norcholestane (NCR) and nordiacholestane ratios (NDR) according to Holba et al. (1998a , b ). The NCR values indicate mostly Cretaceous ages, and Tertiary age is suggested for sample 120.611. The NDR suggests Cretaceous and Upper Jurassic ages...
FIGURES | View All (16)
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Mass-to-charge ratio (m/z) transitions showing the relative abundances of 27-norcholestanes (27-nor), tetracyclic polyprenoid (TPP), C29αααR sterane, and C30 4α-methyl stigmastane (C30–4M) sterane in representative source rocks, respectively. Biomarker codes are listed in Table 3. N18 and Wx98 are oil sample names (Table 2). Es = Shahejie Formation; NL = normalized level.
Published: 15 April 2020
Figure 4. Mass-to-charge ratio ( m / z ) transitions showing the relative abundances of 27-norcholestanes (27-nor), tetracyclic polyprenoid (TPP), C 29 αααR sterane, and C 30 4α-methyl stigmastane (C 30 –4M) sterane in representative source rocks, respectively. Biomarker codes are listed
Journal Article
Journal: AAPG Bulletin
Published: 01 April 2001
AAPG Bulletin (2001) 85 (4): 601–619.
... to other triterpanes on the m / z 191 chromatogram. Calculated 24-norcholestane ratios [24/(24 + 27)-norcholestane] from MRM-GC-MS (metastable reaction monitoring-gas chromatograph-mass spectrometer) for this group of oils are between 0.37 and 0.40. Holba et al. (1998) have documented...
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Tetracyclic polyprenoid (TPP) ratio versus content of C30 24-n-propyldiacholestanes [C30/(C27 + C28 + C29 + C30] for 19 of 37 oil and condensate samples from the West Siberian basin determined by metastable reaction monitoring–gas chromatography–mass spectrometry M+ → mass-to-charge ratio (m/z) 217 and 259. TPP = 2(TPPa)/(2(TPPa) + 27-nor-C26); TPP a = 21S isomer of tetracyclic polyprenoid measured by m/z 414 → 259; 27-nor-C26 = ∑27-norcholestanes. Circle, triangle, rhombus, and star represent samples of families I, II, III-a, and III-b respectively.
Published: 01 March 2016
+ → mass-to-charge ratio (m/z) 217 and 259. TPP = 2(TPPa)/(2(TPPa) + 27-nor-C 26 ); TPP a = 21S isomer of tetracyclic polyprenoid measured by m/z 414 → 259; 27-nor-C 26 = ∑27-norcholestanes. Circle, triangle, rhombus, and star represent samples of families I, II, III-a, and III-b respectively.
Journal Article
Journal: AAPG Bulletin
Published: 11 December 1999
AAPG Bulletin (1999) 83 (12): 1980–2005.
...Figure 11 —Representative metastable reaction monitoring m/z 358 to 217 mass chromatogram for hypersaline lacustrine oils indicates high 24-norcholestane ratios (inset table). ...
FIGURES | View All (22)
Journal Article
Journal: GeoArabia
Publisher: Gulf Petrolink
Published: 01 October 2009
GeoArabia (2009) 14 (4): 53–86.
... predominance. 21-norcholestane is only detected in silicilyte samples. ...
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Journal Article
Published: 05 April 2017
Petroleum Geoscience (2018) 24 (1): 92–101.
...)) are of the order of 0.11 – 0.58 in the oils and bitumen extracts in the dataset ( Table 1 ; Fig. 4 ). The numbers in the ratio, abbreviated to NDR, represent the nor-position. The precursors of the 24-norcholestane biomarkers are diatoms and dinoflagellates ( Rampen et al. 2007 ), which increase in diversity...
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