New uppermost Cambrian U-Pb date from Avalonian Wales and age of the Cambrian-Ordovician boundary

被引：38

作者：

Davidek, K ^{[1
]}

Landing, E

Bowring, SA

Westrop, SR

Rushton, AWA

Fortey, RA

Adrain, JM

机构：

[1] State Educ Dept, New York State Geol Survey, Albany, NY 12230 USA

[2] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA

[3] Brock Univ, Dept Earth Sci, St Catharines, ON K1A 0E8, Canada

[4] Nat Hist Museum, Dept Palaeontol, London SW7 5BD, England

[5] British Geol Survey, Nottingham NG12 5GG, England

来源：

GEOLOGICAL MAGAZINE | 1998年 / 135卷 / 03期

关键词：

D O I：

10.1017/S0016756898008711

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

A crystal-rich volcaniclastic sandstone in the lower Peltura scarabaeoides Zone at Ogof-ddu near Criccieth, North Wales, yields a U-Pb zircon age of 491 +/- 1 Ma. This late Late Cambrian date indicates a remarkably young age for the Cambrian-Ordovician boundary whose age must be less than 491 Ma. Hence the revised duration of the post-Placentian (trilobite-bearing) Cambrian indicates that local trilobite zonations allow a biostratigraphic resolution comparable to that provided by Ordovician graptolites and Mesozoic ammonites.

引用

页码：303 / 309

页数：7

共 41 条

[31]

MILLER JF, 1982, NATIONAL MUSEUM WALE, V3, P155

[32]

Moberg J.C., 1900, GEOLOGISKA FORENINGE, V22, P523, DOI [10.1080/11035890009446922, DOI 10.1080/11035890009446922]

[33] GEOCHRONOLOGY OF THE MOUNT READ VOLCANICS, TASMANIA, AUSTRALIA [J].

PERKINS, C ;

WALSHE, JL .

ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS, 1993, 88 (05) :1176-1197

[34]

Rushton A.W.A., 1982, The Cambrian-Ordovician Boundary: Sections, Fossil Descriptions, and Correlations, Volume 3, P41

[35]

SHERGOLD JH, 1995, 199530 AUSTR GEOL SU

[36]

Skevington D., 1966, Norsk Geologisk Tidsskrift, V46, P111

[37] APPROXIMATION OF TERRESTRIAL LEAD ISOTOPE EVOLUTION BY A 2-STAGE MODEL [J].

STACEY, JS ;

KRAMERS, JD .

EARTH AND PLANETARY SCIENCE LETTERS, 1975, 26 (02) :207-221

[38]

Stubblefield C. J., 1956, P1

[39]

THOMAS AT, 1984, 16 GEOL SOC LOND

[40] EARLY PALEOZOIC CHRONOLOGY - A REVIEW IN LIGHT OF NEW U-PB ZIRCON AGES FROM NEWFOUNDLAND AND BRITAIN [J].

TUCKER, RD ;

MCKERROW, WS .

CANADIAN JOURNAL OF EARTH SCIENCES, 1995, 32 (04) :368-379

← 1 2 3 4 5 →