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Ordovician (系) | |||
Ordovician period; Ordovician | |||
Ordovician (period) | |||
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Ordovician; Ordovician period | |||
Ordovician period (system) | |||
Ordovician period system B | |||
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Ordovician | |||
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Ordovician | |||
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Ordovician |
奥陶纪: 24 phrases in 8 subjects |
Desert science | 3 |
Drilling | 1 |
Earth sciences | 6 |
General | 1 |
Geology | 1 |
Hydroelectric power stations | 3 |
Oil / petroleum | 1 |
Technology | 8 |