How can events in Venezuela affect the markets? 
The country with the largest proven reserves in the world (17.8% of the world total) reduced the volume of production to 1.1 million barrels per day by the end of 2018 (once it was 3.5 mb). Those. the country's total production is less than the planned reduction by OPEC + countries (1.2 mbbs). 
Any decline in production in Venezuela will be happy to be covered by OPEC partners. It turns out that the downside is zero, which cannot be said about the upside - in case of a change of power, the potential for increasing production is substantial. The first reaction in the oil was rather emotional.

Where does the extracted oil go? 
About 500 thousand b / s goes to the United States - Valero, Chevron, Citgo and others. 
The main importer (175 thousand b / s) - Citgo is a subsidiary of PDVSA in the USA, which has 3 refineries, 6 thousand gas stations, 48 ​​terminals, a network of oil pipelines.The total amount of processing up to 70 thousand b / s - 5% of the US market. 
Citgo’s 49.9% stake is pledged to Rosneft, which worries the Americans. Since August 2017 (after the registration of the pledge), sanctions have been imposed restricting Citgo transactions. It was reported about the desire of the Swiss trader Mercuria (partner of Rosneft and Surgut) to acquire the rights of claim for $ 1.5 billion. An application has been filed with an American regulator. 
Citgo also claims the Canadian gold miner Crystallex, whose assets were nationalized in Venezuela. 
About 150 thousand b / c gets Rosneft to repay the debt.

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