Question
Oxygen gas was rare during a period known as the “Boring [this many years].” For 10 points each:
[10e] Give this number of years denoted “G·a,” or “giga annum.”
ANSWER: one billion years [accept ten-to-the-ninth years; accept the Boring Billion]
[10h] In the Canfield Ocean model, the deep ocean has this property due to the lack of oxygen gas during the Boring Billion. Water that is anoxic and sulfidic has this property, whose name derives from Greek for “hospitality.”
ANSWER: euxinic conditions [or euxinia] (The Greek word is “xenia.”)
[10m] Euxinic conditions would have to persist up to this layer in a Canfield Ocean in order to support necessary anoxygenic production. This upper layer of the ocean is typically conflated with the epipelagic zone.
ANSWER: photic zone [or euphotic zone; prompt on sunlight zone by asking “what is its scientific name?”] (Johnston et al. 2009 argues for the necessity of anoxygenic photosynthesis in the Canfield Ocean.)
<Michael Bentley, Science - Earth> ~23830~ <Editor: David Bass>
Data
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| 2024 PACE NSC | 06/08/2024 | Y | 36 | 7.78 | 53% | 19% | 6% |