WELL TRAJECTORY CONTROL TECHNOLOGY FOR SHALLOW HORIZONTAL WELL

The structural configuration at the bottom of viscous oil reservoir in Kelamayi oilfield was a low-angle monocline from northwest to southeast. The dip was 3~9°, itwas of a high permeability and the buried depth was only 200m. So the viscous oil reservoir was developed by vertical wells with a low individual-well producing rate. Four shallow horizontal wells were drilled with slant-angle building-angle holding(horizontal section) type. The depth of slant hole was 493~538m. The vertical depth was 170.60~179. 80m.The horizontal displacement was 403. 50~477. 80m. The length of horizontal section was 201. 08~233. 30m. The ratio of deviated depth and vertical depth was 2. 82~2. 99 and the average individual-well producing rate was four times more than that of vertical wells. This paper introduced the section design, well trajectory control, drlll stem structure of shallow horizontal well and so on.