Results 31 to 40 of about 115,713 (383)

Possible links between extreme oxygen perturbations and the Cambrian radiation of animals

Nature Geoscience, 2019
The role of oxygen as a driver for early animal evolution is widely debated. During the Cambrian explosion, episodic radiations of major animal phyla occurred coincident with repeated carbon isotope fluctuations.
Tianchen He, Maoyan Zhu, Benjamin J. W. Mills, P. Wynn, A. Zhuravlev, R. Tostevin, Philip A. E. Pogge von Strandmann, Aihua Yang, S. Poulton, G. Shields   +9 more
semanticscholar   +1 more source

Paleomagnetic insights into the Cambrian biogeographic conundrum: Did the North China craton link Laurentia and East Gondwana?

Geology, 2020
Redlichiid trilobite and small shelly fossils indicate strong ties of the North China craton (NCC) to Gondwana during the early Cambrian, while recent discoveries of the characteristic fossils of Laurentia in Wuliuan shales in the eastern NCC imply its
Hanqing Zhao, Shihong Zhang, E. al.
semanticscholar   +1 more source

Tectonic history of the South Tannuol Fault Zone (Tuva region of the northern Central Asian Orogenic Belt, Russia) : constraints from multi-method geochronology [PDF]

, 2020
In this study, we present zircon U/Pb, plagioclase and K-feldspar Ar-40/Ar-39 and apatite fission track (AFT) data along the South Tannuol Fault Zone (STFZ).
De Grave, Johan, Mikhailova, Polina, Nachtergaele, Simon, Van Ranst, Gerben, Vetrov, Evgeny, Vetrova, Natalia, Zhimulev, Fedor   +6 more
core   +1 more source

The Qingjiang biota—A Burgess Shale–type fossil Lagerstätte from the early Cambrian of South China

Science, 2019
A treasure trove of Cambrian secrets Animal life exploded in diversity and form during the Cambrian period about 500 million years ago. Fu et al. describe an early Cambrian fossil site in China that contains a variety of specimens, more than half of ...
Dongjing Fu, G. Tong, T. Dai, Wei Liu, Yuning Yang, Y. Zhang, L. Cui, Luoyang Li, Hao Yun, Yu Wu, Ao Sun, Cong Liu, Wenrui Pei, R. Gaines, Xingliang Zhang   +14 more
semanticscholar   +1 more source

Chemostratigraphy of Neoproterozoic carbonates: implications for 'blind dating' [PDF]

, 2001
The delta C-13(carb) and Sr-87/Sr-86 secular variations in Neoproteozoic seawater have been used for the purpose of 'isotope stratigraphy' but there are a number of problems that can preclude its routine use.
Aharon P., Anthony E. Fallick, Anton B. Kuznetsov, Bowring S.A., Brand U., Brasier M.D., Brasier M.D., Brasier M.D., Burns S.J., Calver C.R., Corsetti F.A., Fairchild I.J., Fairchild I.J., Gao G., Gorokhov I.M., Gorokhov I.M., Gorokhov I.M., Grotzinger J.P., Grotzinger J.P., Hoffman P.F., Igor M. Gorokhov, Kaufman A.J., Kennedy M.J., Kirschvink J.L., Knoll A.H., Knoll A.H., Knoll A.H., Kupecz J.A., Kuznetsov A.B., Kuznetsov A.B., Lambert I.B., Magaritz M., McArthur J.M., McArthur J.M., McCulloch M.T., Melezhik V.A., Morton J.P., Ovchinnikova G.V., Pelechaty S.M., Podkovyrov V.N., Pokrovsky B.G., Pokrovsky B.G., Pokrovsky B.G., Saylor B.Z., Semikhatov M.A., Singh U., Smith L.H., Tronnes R.G., Tucker M.E., Tucker M.E., Veizer J., Veizer J., Victor A. Melezhik, Wada S.-I., Walter M.R., Wang Da-Rui   +55 more
core   +1 more source

Cambrian Trilobites [PDF]

Proceedings of the National Academy of Sciences, 1916
USNM ...
openaire   +2 more sources

Accessing Heart Health: A Northern Experience

Online Journal of Rural Nursing and Health Care, 2011
Background and Research Purpose: Coronary heart disease (CHD) continues to be a major cause of death and disability across the globe. Regional differences in CHD exist throughout Canada, including Ontario. It is important to explore the complex interplay
Katherine Timmermans, Ellen Rukholm, Isabelle Michel, Lisa Seto Nielsen, Jennifer Lapum, Robert P Nolan, Jan E Angus   +6 more
doaj   +1 more source

A Cambrian–Ordovician Terrestrialization of Arachnids

Frontiers in Genetics, 2020
Understanding the temporal context of terrestrialization in chelicerates depends on whether terrestrial groups, the traditional Arachnida, have a single origin and whether or not horseshoe crabs are primitively or secondarily marine.
J. Lozano-Fernandez, Alastair R. Tanner, Mark N. Puttick, J. Vinther, G. Edgecombe, D. Pisani   +5 more
semanticscholar   +1 more source

Research on Reservoir Characteristics and Main Controlling Factors of Longwangmiao Formation of Cambrian in Sichuan Basin

Frontiers in Earth Science, 2022
Based on the 4 measured profiles, 17 observation profiles, and 13 drilling core macroscopic and microscopic characteristics of the Cambrian Longwangmiao Formation in the Sichuan Basin, combined with analysis and testing, and reservoir logging ...
Qiang Wang, Qiang Wang, Xingzhi Wang, Xinyao Zeng   +3 more
doaj   +1 more source

Noncrossing partitions and the shard intersection order [PDF]

, 2009
We define a new lattice structure on the elements of a finite Coxeter group W. This lattice, called the shard intersection order, is weaker than the weak order and has the noncrossing partition lattice NC(W) as a sublattice. The new construction of NC(W)
Reading, Nathan
core   +5 more sources