The DOI matches its Crossref record; 60 of the 61 references it cites were found in a registry or an index.
Integrated chemo- and biostratigraphic calibration of early animal evolution: Neoproterozoic–early Cambrian of southwest Mongolia
Abstract
Five overlapping sections from the thick Neoproterozoic to early Cambrian sediments of western Mongolia were analysed to yield a remarkable carbon-isotope, strontium-isotope and small shellyfossil (SSF) record. Chemostratigraphy suggests that barren limestones of sequences 3 and 4, which lie above the two Maikhan Uul diamictites, are post-Sturtian but pre-Varangerian in age. Limestones and dolomites of sequence 5, with Boxonia grumulosa, have geochemical signatures consistent with a post-Varangerian (Ediacarian) age. A major negative δ 13 C anomaly (feature ‘W’) in sequence 6 lies a shortdistance above an Anabarites trisulcatus Zone SSF asemblage with hexactinellid sponges, of probable late Ediacarian age. Anomaly ‘W’ provides an anchor point for cross-correlation charts of carbon isotopes and small shelly fossils. Trace fossil assemblages with a distinctly Cambrian character first appear in sequence 8(Purella Zone), at the level of carbon isotopic feature ‘B’, provisionally correlated with the upper part of cycle Z in Siberia. A paradox is found from sequence 10 to 12 in Mongolia: Tommotian-type SSFs continue to appear, accompanied by Nemakit-Daldynian/Tommotian-type 87 Sr/86 Sr ratios but by increasingly heavyδ 13 C values that cannot be matched in the Tommotian of eastern Siberia. The steady rate of generic diversification in Mongolia also contrasts markedly with the Tommotian ‘diversity explosion’ in eastern Siberia, which occurs just above a major karstic emergence surface. One explanation is that sequences 10 to 12 in Mongolia preserve a pre-Tommotian portion of the fossil record that was missing or removed in easternSiberia. The Mongolian sections certainly deserve an important place in tracing the true course and timing of the ‘Cambrian radiation’.
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In the citing paper
“The chemostratigraphic record from this region is fragmentary because of thick intercalations of siliciclastic sediment from which the δ 13 Ccarb values cannot be read”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al . 1996
In the citing paper
“Anabaritids mark the basal Cambrian strata in Siberia, Mongolia, Kazakhstan, China, India, Iran and Laurentia, but may also occur in the uppermost Ediacaran of Siberia”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al . 1996
In the citing paper
“Voronin et al . (1982) defined the Stenothecoides Zone in Western Mongolia at a level correlated chemostratigraphically (cf. Brasier et al . 1996; Fig. 5) with prominent positive peaks of the uppermost Nemakit-Daldynian Stage of the Siberian Platform”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al . 1996
In the citing paper
“Probably the earliest appearance of Camenella is that reported from Western Mongolian beds at the beginning of the rising trend towards positive peak D”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al . 1996
In the citing paper
“Chemostratigraphic correlation with Siberia (cf. Brasier et al . 1996) suggests that these occurrences are likely pre-dated by Khasagtina primaria Ushatinskaya, 1987 from Western Mongolia”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al . 1996
In the citing paper
“but not younger than those with Siberian δ 13 C feature Z and attributed to the upper Anabarites trisulcatus -lower Purella zones of the NemakitDaldynian Stage”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al. 1996
In the citing paper
“M2 . Protoconodonts Protohertzina unguliformis ; scaly shells of halwaxiids Purella sp.; orthothecid? hyoliths Pseudorthotheca bicostata Qian (indicated as P. bistriata in Khomentovsky & Gibsher, 1996, fig. 13, p. 386) (Brasier et al . 1996, fig. 9; Khomentovsky & Gibsher, 1996, fig. 13).”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al. 1996
In the citing paper
“M2 . Protoconodonts Protohertzina unguliformis ; scaly shells of halwaxiids Purella sp.; orthothecid? hyoliths Pseudorthotheca bicostata Qian (indicated as P. bistriata in Khomentovsky & Gibsher, 1996, fig. 13, p. 386) (Brasier et al . 1996, fig. 9; Khomentovsky & Gibsher, 1996, fig. 13).”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al. 1996
In the citing paper
“M2 . Protoconodonts Protohertzina unguliformis ; scaly shells of halwaxiids Purella sp.; orthothecid? hyoliths Pseudorthotheca bicostata Qian (indicated as P. bistriata in Khomentovsky & Gibsher, 1996, fig. 13, p. 386) (Brasier et al . 1996, fig. 9; Khomentovsky & Gibsher, 1996, fig. 13).”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Brasier et al. 1996
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Self-citation
Metadata
- Authors
- Brasier, M. D., Shields, G., Kuleshov, V. N., & Zhegallo, E. A.
- Affiliations
- University of Oxford (GB)
- Geological Institute (CH)
- Russian Academy of Sciences (RU)
- Venue
- Geological Magazine
- Publisher
- Cambridge University Press (CUP)
- Published
- 1996-07
- Volume
- 133
- Issue
- 4
- Pages
- 445-485
- ISSN
- 0016-7568 (ISSN-L)
- 1469-5081
- OpenAlex
- W2146761970
- Cited by
- 331
- References
- 61
- Citations by year
- 2026: 12 · 2025: 13 · 2024: 9 · 2023: 11 · 2022: 16 · 2021: 13 · 2020: 17 · 2019: 14 · 2018: 11 · 2017: 10 · 2016: 10 · 2015: 8 · 2014: 5 · 2013: 16 · 2012: 8
- FWCI
- 16.71
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Geological Magazine (publishedVersion)
- reroDoc Digital Library (submittedVersion)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geological and Geochemical Analysis
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Evolutionary Biology
- Keywords
- early animal evolution, chemostratigraphy, biostratigraphy, carbon isotopes, strontium isotopes, small shelly fossils, Ediacaran, Cambrian explosion, Tommotian, trace fossils, Siberia
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