Due to the variation of geologic environment reservoir is often invaded by external water, thus, resulting in the property difference between connate water and formation water.

油藏形成后，由于地质环境变化，储层往往会受到外部水系的侵入，从而造成原生水和水层地层水性质的差异。

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Between the reservoir system and the external environment the constant material exchange makes the dynamic reservoir system more complex.

油藏系统与外界不断地进行物质交换，造成油藏动态系统更加复杂化。

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Various natural fractures are the objective reason of leakage in carbonate reservoir, while the tools vibration, stress release and induced fractures are the external reasons of leakage.

天然裂缝发育是工区碳酸盐岩储层漏失的客观原因，钻具震动、应力释放、诱导裂缝是产生井漏的外部原因。

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Every convenience is thought of, and the milk or cream is put in an external stainless steel reservoir the size of a travel coffee cup, which you can keep in the fridge all week, keeps the milk fresher than the container it came in, and easily snaps on when you want milky drinks.

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