Abstract: Type-Y1 water drive characteristic curve is of wider applicability, less parameter required, simpler and quicker calculation than general water drive characteristic curve. This paper studies the rising regularity of water cut in horizontal well in a bottom water reservoir, and presents that the single horizontal well prediction of water cut is on the large deviation using this curve for calculation of the low water-cut stage. By means of limiting the initial water cut of this curve, the performance prediction of the horizontal well in bottom water reservoir is then more satisfactory in effectiveness.

Key words: water-drive characteristic curve, bottom water reservoir, horizontal well, water-cut rising regularity