Even in the ultra-tight Rotliegendes formation (<0.02 md), Tip Screen Out treatments were specified to maximize conductivity and minimize proppant flowback. A 3000-ft horizontal section was stimulated with four transverse fracs. Each frac was designed for 560,000 lbs of ceramic proppant. After the first four fracs were completed, the horizontal well tested at 25 MMCFD at 4350 psi wellhead pressure. Vertical wells in area produced 0.09 MMCFD after perfing, 0.9 MMCFD after acid breakdown and 4.5 MMCFD sustained for 6 years post frac.
This paper outlines the stimulation program used to successfully complete the 15,687 ft (4,783 m) TVD deep horizontal well Soehlingen Z-10 in the tight Rotliegendes sandstone onshore Germany. The program included the breakdown multiple rate injectivity test, use of proppant erosion stages to reduce near wellbore restrictions, and minifrac data analysis. Use of open annulus to analyze the stimulation treatment and modify the design is also covered. Considerations and experiments behind the design and execution of this horizontal well stimulation with hydraulic fractures perpendicular to the wellbore are presented and discussed. The well is now producing at a stable rate of 18 MMSCFD (20,000 m3/hr).
Author(s): I.S. Abou-Sayed, Mobil E & P Technical Center; S. Schueler, Mobil Erdgas-Erdoel GmbH; E. Ehrl, Mobil Erdgas-Erdoel GmbH; W. Hendricks, Halliburton Services Germany, GmbH
Paper Number: SPE 30532