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Steering techniques

IP.com Disclosure Number: IPCOM000237548D
Publication Date: 2014-Jun-23
Document File: 31 page(s) / 1M

Publishing Venue

The IP.com Prior Art Database

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This is the abbreviated version, containing approximately 7% of the total text.

Page 01 of 31

Atty. Docket No. IS13.3744-US-PSP

MONITORING AND REDUCTING FAULT REACTIVATION RISK ON DRILLING

Background

    Geosteering is a process used to manage the trajectory of a borehole based on geological information gathered during a drilling operation, with the goal of reaching specific geological targets. With conventional geosteering operations, a well plan with an expected well path is developed, and while a borehole is being drilled according to the well plan, geological information is gathered so that the well plan can be revised as necessary to reach a desired geological target. The geological information may be gathered, for example, using mud logging, measurement while drilling (MWD) or logging while drilling (LWD).

    During the geosteering or other parts of the drilling operation, a number of geomechanical-related issues occur which may concern the operator. For example, as water depth increases, the safe drilling window becomes narrower due overburden reduction. Furthermore, salt tectonics and geological history in post-salt suggest reduction of horizontal stresses with presence of normal faults. Faulting and folding control the movement and trapping of hydrocarbons. During drilling, this system is perturbed posing problems such as drilling fluid losses or wellbore collapse. During drilling operations and production, this perturbation may pose problems such as fault leakage. FIG. 0 represents a loss of circulation caused by fault reactivation that may occur during the drilling operations and production.

Summary

    One embodiment disclosed herein provides a method to analyze a drilling operation. The method includes utilizing a fault plane method to determine a fault orientation at a location of a geological formation and analyzing that fault orientation. The fault orientation is analyzed with respect to a characteristic of the drilling operation to determine whether the drilling operation will result in a fault reactivation of a fault of the geological formation.

    An alternative embodiment disclosed herein also provides a method to analyze a drilling operation. The method includes utilizing a fault plane analysis method to determine a stress distribution at a location of a geological formation and analyzing that stress distribution. The

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Page 02 of 31

Atty. Docket No. IS13.3744-US-PSP

stress distribution is analyzed with respect to a characteristic associated with the drilling operation to determine whether the drilling operation will result in a fault reactivation of a fault of the geological formation.

Brief Description of the Drawings

FIGURE 0 is a figure illustrating a loss of circulation caused by fault reactivation. FIGURE 1 is a block diagram of an example hardware and software environment for a data processing system in accordance with implementation of various technologies and techniques described herein.

    FIGURES 2A-2D illustrate simplified, schematic views of an oilfield having subterranean formations containing reservoir...