87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland

Yusuke Sawaki, Takahiro Kawai, Takazo Shibuya, Miyuki Tahata, Soichi Omori, Tsuyoshi Komiya, Naohiro Yoshida, Takafumi Hirata, Takeshi Ohno, Brian F. Windley, Shigenori Maruyama

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

The Neoproterozoic-Cambrian Dalradian Supergroup of Scotland contains three glaciogenic sedimentary units, the Port Askaig Formation, the Stralinchy-Reelan Formation, and the Loch na Cille Boulder Bed, in ascending order. Although the idea, that relatively cold climates occurred during the latest Proterozoic, is widely accepted, the cause of the onset of glaciation is still controversial; we use new carbonate 87Sr/86Sr data to better constrain this environmental change. Some Dalradian limestones have high strontium contents (>1000 ppm), low manganese contents and Mn/Sr ratios (87Sr/86Sr values of paleoseawater in the Neoproterozoic. The 87Sr/86Sr values of limestones of the Islay Formation (ca. 0.7067), sampled on the island of Islay, are similar to the values of previous studies. However, the 87Sr/86Sr values of limestones just below the Port Askaig Formation (ca. 0.7064), collected on the island of Garbh Eileach, have the lowest values recorded in the Dalradian Supergroup. Comparing these 87Sr/86Sr values with coeval 87Sr/86Sr values of other regions in the world, such low 87Sr/86Sr (i87Sr/86Sr ratio from the Tonian through the Cryogenian and Ediacaran to the earliest Cambrian. The results show that the 87Sr/86Sr ratio of seawater decreased just before the older Cryogenian glaciation, that it increased by two steps in the early and middle Ediacaran, and that there were at least two abrupt positive excursions in the middle Ediacaran and at the Precambrian-Cambrian boundary. The decline of the 87Sr/86Sr ratio of seawater just before the older Cryogenian Sturtian glaciation suggests that enhancement of weathering, related to break-up of the Rodinia supercontinent and continental flood basalt volcanism, was a likely driver for generating global cooling for the Snowball Earth conditions (Goddéris et al., 2003; Donnadieu et al., 2004).

Original languageEnglish
Pages (from-to)150-164
Number of pages15
JournalPrecambrian Research
Volume179
Issue number1-4
DOIs
Publication statusPublished - May 2010
Externally publishedYes

Fingerprint

chemostratigraphy
Dalradian
Ediacaran
Calcium Carbonate
Carbonates
glaciation
limestone
Seawater
carbonate
Precambrian-Cambrian boundary
seawater
Strontium
Rodinia
flood basalt
supercontinent
Weathering
Manganese
boulder
strontium
manganese

Keywords

  • Dalradian
  • Neoproterozoic
  • Older Cryogenian glaciation
  • Port Askaig Formation
  • Snowball Earth
  • Sr isotope variation

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geology

Cite this

87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland. / Sawaki, Yusuke; Kawai, Takahiro; Shibuya, Takazo; Tahata, Miyuki; Omori, Soichi; Komiya, Tsuyoshi; Yoshida, Naohiro; Hirata, Takafumi; Ohno, Takeshi; Windley, Brian F.; Maruyama, Shigenori.

In: Precambrian Research, Vol. 179, No. 1-4, 05.2010, p. 150-164.

Research output: Contribution to journalArticle

Sawaki, Y, Kawai, T, Shibuya, T, Tahata, M, Omori, S, Komiya, T, Yoshida, N, Hirata, T, Ohno, T, Windley, BF & Maruyama, S 2010, '87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland', Precambrian Research, vol. 179, no. 1-4, pp. 150-164. https://doi.org/10.1016/j.precamres.2010.02.021
Sawaki, Yusuke ; Kawai, Takahiro ; Shibuya, Takazo ; Tahata, Miyuki ; Omori, Soichi ; Komiya, Tsuyoshi ; Yoshida, Naohiro ; Hirata, Takafumi ; Ohno, Takeshi ; Windley, Brian F. ; Maruyama, Shigenori. / 87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland. In: Precambrian Research. 2010 ; Vol. 179, No. 1-4. pp. 150-164.
@article{6626a7b5bc074ed59195dfbb6ec6fb34,
title = "87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland",
abstract = "The Neoproterozoic-Cambrian Dalradian Supergroup of Scotland contains three glaciogenic sedimentary units, the Port Askaig Formation, the Stralinchy-Reelan Formation, and the Loch na Cille Boulder Bed, in ascending order. Although the idea, that relatively cold climates occurred during the latest Proterozoic, is widely accepted, the cause of the onset of glaciation is still controversial; we use new carbonate 87Sr/86Sr data to better constrain this environmental change. Some Dalradian limestones have high strontium contents (>1000 ppm), low manganese contents and Mn/Sr ratios (87Sr/86Sr values of paleoseawater in the Neoproterozoic. The 87Sr/86Sr values of limestones of the Islay Formation (ca. 0.7067), sampled on the island of Islay, are similar to the values of previous studies. However, the 87Sr/86Sr values of limestones just below the Port Askaig Formation (ca. 0.7064), collected on the island of Garbh Eileach, have the lowest values recorded in the Dalradian Supergroup. Comparing these 87Sr/86Sr values with coeval 87Sr/86Sr values of other regions in the world, such low 87Sr/86Sr (i87Sr/86Sr ratio from the Tonian through the Cryogenian and Ediacaran to the earliest Cambrian. The results show that the 87Sr/86Sr ratio of seawater decreased just before the older Cryogenian glaciation, that it increased by two steps in the early and middle Ediacaran, and that there were at least two abrupt positive excursions in the middle Ediacaran and at the Precambrian-Cambrian boundary. The decline of the 87Sr/86Sr ratio of seawater just before the older Cryogenian Sturtian glaciation suggests that enhancement of weathering, related to break-up of the Rodinia supercontinent and continental flood basalt volcanism, was a likely driver for generating global cooling for the Snowball Earth conditions (Godd{\'e}ris et al., 2003; Donnadieu et al., 2004).",
keywords = "Dalradian, Neoproterozoic, Older Cryogenian glaciation, Port Askaig Formation, Snowball Earth, Sr isotope variation",
author = "Yusuke Sawaki and Takahiro Kawai and Takazo Shibuya and Miyuki Tahata and Soichi Omori and Tsuyoshi Komiya and Naohiro Yoshida and Takafumi Hirata and Takeshi Ohno and Windley, {Brian F.} and Shigenori Maruyama",
year = "2010",
month = "5",
doi = "10.1016/j.precamres.2010.02.021",
language = "English",
volume = "179",
pages = "150--164",
journal = "Precambrian Research",
issn = "0301-9268",
publisher = "Elsevier",
number = "1-4",

}

TY - JOUR

T1 - 87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian carbonates below the Port Askaig Glaciogenic Formation, Scotland

AU - Sawaki, Yusuke

AU - Kawai, Takahiro

AU - Shibuya, Takazo

AU - Tahata, Miyuki

AU - Omori, Soichi

AU - Komiya, Tsuyoshi

AU - Yoshida, Naohiro

AU - Hirata, Takafumi

AU - Ohno, Takeshi

AU - Windley, Brian F.

AU - Maruyama, Shigenori

PY - 2010/5

Y1 - 2010/5

N2 - The Neoproterozoic-Cambrian Dalradian Supergroup of Scotland contains three glaciogenic sedimentary units, the Port Askaig Formation, the Stralinchy-Reelan Formation, and the Loch na Cille Boulder Bed, in ascending order. Although the idea, that relatively cold climates occurred during the latest Proterozoic, is widely accepted, the cause of the onset of glaciation is still controversial; we use new carbonate 87Sr/86Sr data to better constrain this environmental change. Some Dalradian limestones have high strontium contents (>1000 ppm), low manganese contents and Mn/Sr ratios (87Sr/86Sr values of paleoseawater in the Neoproterozoic. The 87Sr/86Sr values of limestones of the Islay Formation (ca. 0.7067), sampled on the island of Islay, are similar to the values of previous studies. However, the 87Sr/86Sr values of limestones just below the Port Askaig Formation (ca. 0.7064), collected on the island of Garbh Eileach, have the lowest values recorded in the Dalradian Supergroup. Comparing these 87Sr/86Sr values with coeval 87Sr/86Sr values of other regions in the world, such low 87Sr/86Sr (i87Sr/86Sr ratio from the Tonian through the Cryogenian and Ediacaran to the earliest Cambrian. The results show that the 87Sr/86Sr ratio of seawater decreased just before the older Cryogenian glaciation, that it increased by two steps in the early and middle Ediacaran, and that there were at least two abrupt positive excursions in the middle Ediacaran and at the Precambrian-Cambrian boundary. The decline of the 87Sr/86Sr ratio of seawater just before the older Cryogenian Sturtian glaciation suggests that enhancement of weathering, related to break-up of the Rodinia supercontinent and continental flood basalt volcanism, was a likely driver for generating global cooling for the Snowball Earth conditions (Goddéris et al., 2003; Donnadieu et al., 2004).

AB - The Neoproterozoic-Cambrian Dalradian Supergroup of Scotland contains three glaciogenic sedimentary units, the Port Askaig Formation, the Stralinchy-Reelan Formation, and the Loch na Cille Boulder Bed, in ascending order. Although the idea, that relatively cold climates occurred during the latest Proterozoic, is widely accepted, the cause of the onset of glaciation is still controversial; we use new carbonate 87Sr/86Sr data to better constrain this environmental change. Some Dalradian limestones have high strontium contents (>1000 ppm), low manganese contents and Mn/Sr ratios (87Sr/86Sr values of paleoseawater in the Neoproterozoic. The 87Sr/86Sr values of limestones of the Islay Formation (ca. 0.7067), sampled on the island of Islay, are similar to the values of previous studies. However, the 87Sr/86Sr values of limestones just below the Port Askaig Formation (ca. 0.7064), collected on the island of Garbh Eileach, have the lowest values recorded in the Dalradian Supergroup. Comparing these 87Sr/86Sr values with coeval 87Sr/86Sr values of other regions in the world, such low 87Sr/86Sr (i87Sr/86Sr ratio from the Tonian through the Cryogenian and Ediacaran to the earliest Cambrian. The results show that the 87Sr/86Sr ratio of seawater decreased just before the older Cryogenian glaciation, that it increased by two steps in the early and middle Ediacaran, and that there were at least two abrupt positive excursions in the middle Ediacaran and at the Precambrian-Cambrian boundary. The decline of the 87Sr/86Sr ratio of seawater just before the older Cryogenian Sturtian glaciation suggests that enhancement of weathering, related to break-up of the Rodinia supercontinent and continental flood basalt volcanism, was a likely driver for generating global cooling for the Snowball Earth conditions (Goddéris et al., 2003; Donnadieu et al., 2004).

KW - Dalradian

KW - Neoproterozoic

KW - Older Cryogenian glaciation

KW - Port Askaig Formation

KW - Snowball Earth

KW - Sr isotope variation

UR - http://www.scopus.com/inward/record.url?scp=77950565877&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77950565877&partnerID=8YFLogxK

U2 - 10.1016/j.precamres.2010.02.021

DO - 10.1016/j.precamres.2010.02.021

M3 - Article

AN - SCOPUS:77950565877

VL - 179

SP - 150

EP - 164

JO - Precambrian Research

JF - Precambrian Research

SN - 0301-9268

IS - 1-4

ER -