ライフサイエンスコーパス: Proterozoic

1 a build-up of atmospheric oxygen before the Proterozoic.

2 gical and geochemical conditions in the late Proterozoic.

3 for the rise of metazoans at the end of the Proterozoic.

4 on of Earth's surface environment during the Proterozoic.

5 deposits formed during the Archean and early Proterozoic.

6 nental stabilization at the beginning of the Proterozoic.

7 onate could have been relevant since the mid-Proterozoic.

8 arine sulphate concentrations throughout the Proterozoic.

9 wo isochrons, one Archaean (2.95 Ga) and one Proterozoic (1.15 Ga).

10 xidation of Cr at Earth's surface in the mid-Proterozoic (1.8 to 0.8 billion years ago).

11 he most abundant type of fossil found in the Proterozoic (2,500 to 590 Myr ago), but they then declin

12 mats in benthic environments for most of the Proterozoic (2,500-542 Mya), marine planktonic cyanobact

13 ks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons.

14 coincident with a major regime change in the Proterozoic acritarch record, including: (i) disappearan

15 cean environmental conditions earlier in the Proterozoic adverse to nitrogen-fixers and their evoluti

16 The Proterozoic aeon (2,500-540 million years ago) saw episo

17 a from rocks formed near the boundary of the Proterozoic and Archaean eons, some 2.5 Gyr ago, show ma

18 All phylogenetic dating in the Proterozoic and before is difficult: Significant debates

19 cyanobacteria evolved towards the end of the Proterozoic and early Phanerozoic.

20 oth anomalous climatic stasis during the mid-Proterozoic and extreme climate perturbation during the

21 ntrolling the level of oxygen throughout the Proterozoic and its eventual rise remain uncertain.

22 The transition between the Proterozoic and Phanerozoic eons, beginning 542 million

23 and mean temperature of cold periods within Proterozoic and Quaternary climates, and recent climate

24 the microbially dominated ecosystems of the Proterozoic and the Cambrian emergence of the modern bio

25 ains in the sandstone are Permian, Devonian, Proterozoic, and Archean in age and, with the exception

26 ulphide in injected sands extend back to the Proterozoic, and show that injected sand complexes have

27 organic-walled microfossils extracted from a Proterozoic ( approximately 1.4-gigayear-old) shale in N

28 erstanding of ocean chemistry during the mid-Proterozoic ( approximately 1.8-0.8 Ga).

29 r-filled structures common in early- and mid-Proterozoic ( approximately 2,500-750 million years ago,

30 We propose that the root formed during the Proterozoic assembly of interior East Antarctica (possib

31 was abundant in the late Archaean and early Proterozoic atmosphere and that methane was probably sca

32 The tidal rhythmites in the Proterozoic Big Cottonwood Formation (Utah, United State

33 served crustal thickness across the Archaean/Proterozoic boundary, these data are consistent with a m

34 nts phosphorus and nickel across the Archean-Proterozoic boundary, which might have helped trigger th

35 obialites were common and diverse during the Proterozoic, but declined in abundance and morphological

36 gered by environmental perturbation near the Proterozoic-Cambrian boundary and subsequently amplified

37 The terminal event, at the Proterozoic-Cambrian boundary, signals the final diminut

38 The Proterozoic-Cambrian transition records the appearance o

39 Here we use a simple box model of a generic Proterozoic coastal upwelling zone to show how these fee

40 ents indicate expanded anoxia during the mid-Proterozoic compared to the present-day ocean.

41 is implies not only that cyanobacteria built Proterozoic conical stromatolites but also that fossil b

42 overt assembly of Rodinia from thickened mid-Proterozoic continental crust via two-sided subduction c

43 r H2S-rich seawaters that were widespread in Proterozoic continental margins.

44 ion beneath Venetia from the Archaean to the Proterozoic.Dating of inclusions within diamonds is used

45 d that the metal enrichment record implies a Proterozoic deep ocean characterized by pervasive anoxia

46 The 1.8 billion years younger Proterozoic diamond suite formed by melt-dominated metas

47 hermal and chemical evolution of the Archean-Proterozoic Earth.

48 urred in two rapid steps at both ends of the Proterozoic Eon ( approximately 2.5-0.543 Ga).

49 road steps near the beginning and end of the Proterozoic eon (2,500 to 542 million years ago).

50 Recent data imply that for much of the Proterozoic Eon (2500 to 543 million years ago), Earth's

51 2.3 billion years ago, Gyr ago) and the late Proterozoic eon (about 0.8 Gyr ago), with the latter imp

52 orus cycle may have occurred during the late Proterozoic eon (between 800 and 635 million years ago),

53 e record of marine carbon indicates that the Proterozoic Eon began and ended with extreme fluctuation

54 ed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing

55 ich environments in the late Archean Eon and Proterozoic Eon, respectively, by the spread of arsM gen

56 ies a unique ocean chemistry for much of the Proterozoic eon, which would have been neither completel

57 the environmental transformation late in the Proterozoic eon.

58 haps five) discrete ice ages in the terminal Proterozoic Eon.

59 e of major animal clades occurred during the Proterozoic Eon.

60 genation of Earth's surface ocean during the Proterozoic Eon.

61 al patterns of volcanism, as far back as the Proterozoic eon.

62 of Eucarya occurred in the late Archaean or Proterozoic Eons when atmospheric oxygen levels were low

63 however, extend into the Archaean and early Proterozoic eons, in the form of impact spherule beds: g

64 e balance during the late Archaean and early Proterozoic eons.

65 e concentrations may have changed during the Proterozoic era (2.5-0.54 Gyr ago).

66 ets may have reached the Equator in the late Proterozoic era (600-800 Myr ago), according to geologic

67 ection of eukaryotic phytoplankton since the Proterozoic era.

68 and subaerially exposed habitats during the Proterozoic era.

69 From the late Archaean to late Proterozoic eras (some 3-1 billion years ago), much of t

70 's oceans during the late Archaean and early Proterozoic eras.

71 ay thus help to explain observed patterns of Proterozoic evolution.

72 preserved and distinctive assemblage of Late Proterozoic fossils from subtidal marine shales.

73 Exceptional preservation of Proterozoic fossils is not unknown, but it is usually as

74 We describe a Proterozoic, fully biomineralized metazoan from the Omky

75 Proterozoic glacial deposits laid down in near-equatoria

76 this redox syntrophy in anoxic and microoxic Proterozoic habitats LECA evolved.

77 spheric oxygen concentration during the late Proterozoic has been inferred from multiple indirect pro

78 idence for such low O2 concentrations in the Proterozoic helps explain the late emergence and diversi

79 mains the most viable model for low-latitude Proterozoic ice ages.

80 However, empirical estimates of Proterozoic levels of atmospheric carbon dioxide concent

81 arest and most taxonomically varied views of Proterozoic life yet reported.

82 the Sierran batholith formed on preexisting Proterozoic lithosphere, most of the original lithospher

83 Recent evidence for H(2)S in some mid-Proterozoic marine basins suggests, however, that the de

84 Trace metal data for Proterozoic marine euxinic sediments imply that the expa

85 ere we present iron data from a suite of mid-Proterozoic marine mudstones.

86 ve anoxia in the subsurface ocean during the Proterozoic may have allowed large fluxes of biogenic CH

87 /188Os ratios (0.1193 to 0.1273), which give Proterozoic model ages of 820 to 1230 million years ago.

88 s after about 1,800 Myr ago maintained a mid-Proterozoic molybdenum reservoir below 20 per cent of th

89 oxygen generated during Archean and earliest Proterozoic non-Snowball glacial intervals could have dr

90 would have influenced oceanic redox and the Proterozoic O(2) budget.

91 he iron-replete reducing environments of the Proterozoic ocean [1].

92 The oxidation state of the Proterozoic ocean between these two steps and the timing

93 nktonic productivity, various models for mid-Proterozoic ocean chemistry imply different effects on t

94 e to show how these feedbacks caused the mid-Proterozoic ocean to exhibit a spatial/temporal separati

95 diverse palaeogeographic settings in the mid-Proterozoic ocean, inviting new models for the temporal

96 stem-group cnidarians that lived in the late Proterozoic ocean.

97 much dissolved oxygen was present in the mid-Proterozoic oceans between 1.8 and 1.0 billion years ago

98 The redox chemistry of Proterozoic oceans has important implications for evolut

99 Thus, a redox structure similar to those in Proterozoic oceans may have persisted or returned in the

100 suggest that subsurface water masses in mid-Proterozoic oceans were predominantly anoxic and ferrugi

101 modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen

102 olved more than 1.5 billion years ago in the Proterozoic oceans.

103 ndicating low sulphate concentrations in mid-Proterozoic oceans.

104 ented the occurrence of microborings in late Proterozoic ooids from central East Greenland.

105 Late Proterozoic organisms must have been diverse and widely

106 s C) and show evidence for heating and yield Proterozoic Os model ages, whereas the deeper portions (

107 harply constraining the magnitude of the end-Proterozoic oxygen increase.

108 state of the oceans, generated by the early Proterozoic oxygen revolution and terminated by the envi

109 ain extreme carbon isotope variations in the Proterozoic, Paleozoic, and Triassic.

110 d of the East African orogen during the late Proterozoic pan-African orogenic event.

111 Sedimentary rocks deposited across the Proterozoic-Phanerozoic transition record extreme climat

112 the divergence of living agnathans, near the Proterozoic/Phanerozoic boundary (approximately 550Mya).

113 f western North America some younger (middle Proterozoic) regions have remained stable, whereas some

114 Although suitable Proterozoic rocks exist, no currently known Archean stra

115 yanobacterial sheaths routinely preserved in Proterozoic rocks, this assemblage includes multicellula

116 nt in 13C relative to Phanerozoic or earlier Proterozoic samples.

117 at provided by Ediacaran fossils in terminal Proterozoic sandstones and shales.

118 Here, we present a Proterozoic seawater sulfate isotope record that include

119 ally continuous suites of samples from Upper Proterozoic sedimentary successions of East Greenland, S

120 overlooked--constituent of Archean and Early Proterozoic sedimentary successions.

121 f chromium (Cr) isotope data from a suite of Proterozoic sediments from China, Australia, and North A

122 ere we show that hydrocarbons extracted from Proterozoic sediments in several locations worldwide are

123 g-distance correlation between fossiliferous Proterozoic strata of Mexico and the United States.

124 entary changes, including the replacement of Proterozoic-style microbial matgrounds by Phanerozoic-st

125 alt, the HIMU source formed as Archean-early Proterozoic subduction-related carbonatite-metasomatized

126 Efforts to reconstruct Proterozoic supercontinents are strengthened by this dem

127 rom sulfur isotope data for Archean to early Proterozoic surface material in the deep HIMU mantle sou

128 Subsequent Proterozoic tectonic and magmatic events altered the com

129 n hydrated and probably weakened much of the Proterozoic tectospheric mantle beneath the Colorado pla

130 n of animal life on Earth for much of Middle Proterozoic time ( approximately 1.8-0.8 billion years a

131 reviving the faint young Sun paradox during Proterozoic time and challenging existing models for the

132 During Proterozoic time, Earth experienced two intervals with o

133 role of CH4 in Earth's climate system during Proterozoic time.

134 Late Proterozoic to modern sediments may reflect greater Fe(I

135 nently oxygenated atmosphere at the Archaean-Proterozoic transition (approximately 2.5 billion years

136 d permanently diminished during the Archaean-Proterozoic transition.

137 , the assumption of elevated pCH4 during the Proterozoic underlies most models for both anomalous cli

138 wn, but it is generally assumed that the mid-Proterozoic was home to a globally sulphidic (euxinic) d

139 significant non-arc magmatism during the mid-Proterozoic, while fewer occurrences of many other miner