The so-called spot crude oil explosion refers to the situation that the balance of settlement reserve in the investor's margin account is zero or negative, and the investor is forced to close the position because he can't meet the requirements of additional margin within the specified time. When the market situation changes greatly, if most of the funds in the investor's margin account are occupied by trading margin, and the trading direction is opposite to the market trend, it is easy to explode the position because of the leverage effect of margin trading. When the "gold explosion" happens, investors must make up for the losses in time, otherwise they will face legal recourse. In order to avoid this situation, it is necessary to control positions, manage funds reasonably, and avoid Man Cang operations like stock trading. And track the market in time, and you can't buy it like a stock market. There are two kinds of empty positions. One case is that the futures customer still owes money to the futures exchange after closing the position, that is, the floating profit and loss of the account is ≥ the total amount of funds in the account, that is, the customer's equity is ≤0. In the second case, because the market changes too fast, the deposit in the investor's account can't maintain the original contract before the deposit is added. This kind of margin "zeroing" caused by forced liquidation due to insufficient margin is commonly known as "short position", and the meaning of "short position" is the same as "short position".