Venezuela officially has the world’s largest proven oil reserves at about 303 billion barrels, roughly 17% of global crude. Most of this oil is found in the Orinoco Belt, where the crude oil is extra-heavy and dense. The huge reserves formed over millions of years, as rivers and changing sea levels helped trap organic material in deep basins. Natural geological traps sealed this material as oil underground. However, Venezuela’s large reserves do not mean high oil production today. Once producing 3.7 million barrels per day, output has fallen to around 1 million barrels due to many challenges. The heavy crude oil is thick and difficult to extract and refine. It requires special equipment and mixing with lighter hydrocarbons before it can be sold internationally. Decades of underinvestment, old facilities, mismanagement, and international sanctions have damaged the country’s oil infrastructure. Pipelines, wells, and refineries are below capacity and need big repairs and upgrades. Sanctions restrict access to global markets, money, and technology, further limiting production. Luisa Palacios of Columbia University said in a podcast, "Venezuela once produced 3.7 million barrels per day ... production has dropped to around 1 million barrels per day, a fraction of what the country could theoretically supply." The result is a big difference between Venezuela’s underground oil reserves and its actual oil wealth today. The vast amount of heavy crude oil underground counts toward reserve numbers but has not translated into strong production or export earnings in recent years.