Cave and cleft in karst limestone are the main oil-bearing space of Ordovician oil poor in Tahe oil field, the develop level of ancient karst controlled the formation oil pool in Ordovician reservoir.

塔河油田奥陶系油藏储集空间以碳酸盐岩岩溶孔洞缝为主，古岩溶发育程度对奥陶系油气成藏有重要的控制作用。

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Mongolia, although poor, has considerable untapped resources of oil and minerals.

蒙古虽然贫穷，却有相当储量未利用的石油和矿物资源。

《柯林斯英汉双解大词典》

Watercolour still seems somehow to be the poor relation of oil painting.

水彩画似乎仍比油画略逊一筹。

《柯林斯英汉双解大词典》

He says it is poor countries that will be hit hardest by a downturn in oil supplies.

VOA: standard.2009.10.20

But in November 2005, it signed a deal with the US state of Massachusetts to provide cheap heating oil to poor households.

BBC: NEWS | UK | England | London | Mayor signs Venezuelan oil deal

In an oil-poor country where tourism is the second-largest foreign exchange earner (after phosphate exports) that generates some 20% of GDP, passage of any anti-alcohol measure could cause a net loss of more than 300, 000 jobs.

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Even oil-poor countries are winning.

ECONOMIST: A high oil price will delay reforms