Many sedimentary rocks contain such features as ripple marks, exactly like those we can see forming in sediments at the bottom of present-day lakes or shallow seas.

我们可以看到，现在的湖底或浅海底部的沉积物中形成了波痕。许多沉积岩都含有类似这种波痕的特征。

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Occurrence of both carbonate and siliciclastic sources, active hydrodynamic regimes, alternate dry and wet climates, and the fluctuation of sea level are main factors for forming mixed sediments.

形成混合沉积的条件是具备碳酸盐和硅质碎屑两类物源、活跃的水动力和干湿交替的气候，此外，海平面的相对波动也会造成积极的影响。

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Rare earth elements (REE) have important tracing significance on studies about sedimentation environment, source and forming of sediments.

稀土元素(REE)在揭示沉积环境，研究沉积物物源及成因方面具有重要的示踪意义。

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To replace earlier finds, oil companies moved offshore, where rivers have been depositing petroleum-forming sediments for millions of years.

FORBES: Going deep