LithoTarge

Services

It has been widely acknowledged that core handling is critical to the maintenance of core integrity. Unfortunately, cores often don’t undergo adequate handling procedures

The rig site handling of unconsolidated core is a risky process that might hamper core integrity if appropriate procedures are utilized.

The main purpose of core preservation is to retain the pore fluids in the undisturbed core samples thus preventing saturation and wettability alteration.

Cases of invasion of core-stabilization products into fractures are often seen. This represents a common and often serious problem in the subsequent geological description of slabbed cores.

The fundamental objective of coring is to obtain core that is representative of the reservoir rock properties.

StoreCore primarily serves the Oil Industry but also provides services to numerous Universities and Research Institutions.

Kirk Petrophysics provides expert on-site core handling services.

It has been widely acknowledged that core handling is critical to the maintenance of core integrity. Unfortunately, cores often don’t undergo adequate handling procedures

to ensure that quality data can be obtained from core measurements.The economic impact of erroneous analysis can be massive especially when the consequences of inferior or inadequate data are not fully realized. To obtain a good core, Kirk Petrophysics offers an advanced method for core stabilization. This stabilization method along with expert supervision and quality control of core handling at the well site, guarantees a substantial improvement in core quality. When required, this service can be offered in the laboratory too. An independent-expert report including recommendations will be submitted to ensure good quality core and thus high quality reservoir data.

All our methods and recommendations are based on extensive experience and broad knowledge of core handling and core analysis This holds for consolidated and for friable and soft reservoir sediments both in the area of services and research.

Advantages of Lithotarge stabilization

The core is immediately accessible for geological description and determination of slabbing orientation after peeling off the Lithotarge
Because of the LithoTarge confinement of the core, a window can be cut over the entire length of the core-barrel allowing e.g. white light and Ultra Violet light photography
Lithotarge is invisible on CT-scans - Lithotarge provides an excellent cushion against external damage
Expanding Lithotarge squeezes out any mud from the annulus between core and inner barrel and therefore the injection process can be done while the core is horizontally positioned
Core length up to 30 feet can be successfully Lithotarge stabilized
Because of the easy process of LithoTarge injection manipulation of the core is minimal - The small amounts of solvents, if any, used in this process are within acceptable limits regarding health and safety. This is particularly true when compared to other stabilization methods.
Lithotarge has a proven preservation capacity for a period of at least one week.

Lithotarge - full core length Full core length
Because of the adaptability of Lithotarge, a quick on site inspection of the core condition allows the decision regarding the optimal method of stabilization to apply. For example, for extremely fragile sediments, stabilization of the full barrel length would be recommended. This avoids any possible disturbance during cutting the core barrel into smaller sections.

Lithotarge injection holes are normally made every 1ft along the core barrel but this can be different and depends on the decision of the onsite technician. These injection holes are drilled to ensure full encapsulation and easy expulsion of the mud.

Depending on the progress of the Lithotarge along the tube annulus, lateral injection holes may be drilled to ensure full encapsulation and a more easy expulsion of the mud. After the full length has been stabilized, the core barrel is cut into defined sections (e.g. 1m, 30cm …) and placed on the core lay out table for further processing.

Lithotarge - short core section Short core section
The one meter length injection is the most common method applied to stabilize medium cemented to consolidated core. The technique is applied immediately after sawing the core barrel in short sections. The sections are carefully transferred to a core lay out table where they remain at all times in horizontal position.

The LithoTarge injection as for the full length injection does not require draining the mud. This will be displaced by LithoTarge in a later stage. Prior to injection, the core-handling engineer examines the annulus between the core and core barrel in order to define the injection procedure that guarantees the optimal LithoTarge encapsulation.

It should be noted that the core remains horizontal all the time of the stabilization process, i.e. mud should not be drained in order to prevent any core movement with a change to damage the core.

Lithotarge - core in verticle position Core in vertical position
The vertical stabilization technique is applied when the formation is qualified as extremely soft (loose sand) and any movement, while the core is in horizontal position, will cause harm to the core. Sometimes a special technique is applied when the core is recovered at the drill floor. This technique allows the inner-core barrel to be cut into short pieces by using a specially designed pipe cutter.

During this process the core remains vertical all the time. After cutting, an end cap, with an insert, is placed at the bottom of the core section. This insert allows LithoTarge to be injected into the end cap providing a cushion on which the core section can rest.