Abstract:Weibei depression is a secondary depression basin in Changwei depression. It is also a traditional oil and gas exploitation area. Thick dark mudstone, shale and oil shale are sedimented in the second section of Kongdian formation in Weibei depression. They are good hydrocarbon source rocks and raw shale gas reservoir in Weibei depression. In this paper, through analyzing the scene analytical experiment data of Canyi well in Changyel, the corresponding relation of the loss of gas, loss of time, sample depth, lithology and the analysis of gas in the second section of Kongdian formation in Weibei depression have been studied. As showed by the analysis of the scene analytical experiment data, it is indicated that the loss of gas is greater than the analytical gas. The variation trend is uniform, that is when the depth is similar and the lithology is the same, analytical gas will increase accompanying with the decrease of the loss of time; when the depth is similar, the analytical gas of the mudstone is greater than the silty mudstone; when the lithology is the same, the analytical gas will increase accompanying with the growth of the depth, and the growth rate will decrease accompanying with the growth of the depth.