Gap cap entrapment composite well completion method

Abstract

The invention discloses a gap cap entrapment composite well completion method. The method comprises the following steps of (a) performing an Nth well drilling operation to the upper stratum of a gas cap, running in technical casing pipes, performing well cementation, cementation waiting and pressure test, wherein N>=1; (b) after pressure is tested to be qualified, performing an (N+1)th well drilling operation until penetrating the gas cap and a reservoir and reaching the lower stratum of the reservoir to finish drilling; (c) in the (N+1)th well, running a tail pipe into an upper casing pipe, and running the pipe shoe of the tail pipe into the reservoir; (d) cementing the tail pipe section for well cementation to extend the cemented section to the tail hanger of the tail pipe; (e) performing cementation waiting, drilling a cement plug at the tail shoe of the tail pipe until reaching the well bottom, and pulling out of hole; (f) running a perforating gun into the tail pipe section inside the reservoir to performing perforating operation. The gap cap entrapment composite well completion method is applied to solving the problem that gas cap entrapment well completion manners in the prior art are prone to lead to low productivity, and achieving the aim of increasing the seepage area and improving the single well productivity.

Description

technical field [0001] The invention relates to the field of well completion of oil and gas wells, in particular to a composite well completion method for gas cap traps. Background technique [0002] In oil and gas reservoirs, oil, gas, and water often coexist in the same trap, and are vertically distributed according to different densities. Natural gas with the lightest density occupies the top of the trap, so it is called the gas cap. There are cap rocks at the top of the trap, and the cap rock is generally composed of tight mud shale. For the reservoir in the trap, the free gas inside the reservoir will diffuse upwards to the cap rock after overflowing, so if the reservoir If there is a gas cap above the formation, it is easy to form an abnormally pressured formation, which increases the difficulty of drilling engineering and later mining. Therefore, in the prior art, for traps with gas caps, the general practice is to directly drill through the gas cap and the reservoir...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a composite well completion method for gas cap traps, so as to solve the problem in the prior art that the well completion methods for gas cap traps easily lead to low productivity, and to increase seepage area and single well productivity the goal of

Images