Field of the invention

[0001] The present invention relates to the technical field of installation and monitoring tracers and controlling influx zones in a petroleum production well. More specific the invention is a method for placing tracers by applying a pipe length, a patch, carrying tracers, for flow release, wherein the patch is arranged for anchoring, perforating and expanding to seal off an influx zone based on monitoring results.

Background art

[0002] Today tracers are deployable in new wells, but presently no viable solution has been matured for retrofit applications to place permanently installed tracers into an existent completion and/or producing well.

Some known methods for tracer installations are;

*Pumping tracers via injection well; limited to give information of the flow from this injection well.

*Injecting into the pipeline direct to the flow; the injection, production and sampling will take place more or less simultaneously. The tracer will follow the production flow in which it is injected and not provide long term monitoring.

*Placing tracers together with the completion - gives information about the flow from the zones where the tracers were placed (WO0181914A1, US200305652A1)

*Shoot into the formation - prior to completion

*Injection to the formation (W09533121 ) a tool lowered and injection direct into the borehole wall - prior to completion

The three lower methods all has to be carried out prior to completion of the well. Short summary of the invention

[0003] A main object of the present invention is to disclose a method and a system for tracer marking and monitoring of a petroleum well with one or more production zones comprising placing tracers at desired zones in a petroleum well with a production tubing, a casing or a liner with perforations at the zones, and comprising; lowering one or more patch-tubes into the well to a desired depth in a way that the one or more patch-tubes extends into the production tubing along on or more of the zones; wherein the patch is divided in one or more patch zones along the patch, wherein each patch zone comprises one or more tracer sources with one or more unique tracers arranged to release to produced fluids, in desired positions, and further comprises one or more radial expandable patch portions arranged to be expanded, upon desire, to sealing against the tubing, anchoring an anchor of the patch to the tubing, allowing the well to produce well fluids and monitoring the production flow with respect to tracers.

An advantage of the method is that one may install tracers into the tubing after the well has been completed. The tracers may also be installed after a time of production and based on information from well analysis carried out after a time of production, as well. This gives the possibility of very well designed tracer sources for placing at particular inflow zones etc

[0004] The invention also is a system for arranging tracers inside a tube in petroleum (hydrocarbon) well comprising a length of a tube formed patch with outer diameter less than an inner diameter of the tube, wherein the patch is divided in one or more patch zones along the patch;

wherein each patch zone comprises

- one or more tracer sources with one or more tracers

- one or more radial expandable patch portions.

[0005] Advantage to the system is that it is a system enabling retrofit installation into a well without, with wrong, or with empty tracer sources. The tracer patch system should be tailor made to the specific well that it will be installed into. Another advantage is that the radial expandable portions may be used to seal of a production zone upon desire. Yet another advantage is that this method allows the simultaneous operation of sealing off a zone in the well and installing tracer monitoring systems in the same run, thus saving operational time at the installation rig.

Figure captions

The attached figures illustrate some embodiments of the claimed invention.

[0006] Fig. 0 is a simplified sketch and illustrates an initial situation with a cemented (first annulus) production liner as an example of a production well without tracers, prior to a retrofit installation of tracers according to the invention. The first annulus (Al) could also have other types of fill (101) or zonal restrictions than cement (101), such as gravel pack that is permeable between the formation and the production pipe, but not particularly permeable along the annulus but almost like "sand aband", packers or epoxy injections. The well, the annulus fill, the casing etc. is not a part of the invention as such.

[0007] Fig. l is a section cut along the longitudinal axis of a well with a liner, casing or the like, and a patch and illustrates a simple embodiment of the invention and shows a patch (1) inserted into a well with one illustrated production zone wherein the liner or casing (6) is perforated (pi). The patch has one patch portion (111) with tracer sources

(Tl, T2...Ti) with tracers (Trl, Tr2 Tri) attached to it and anchored in its lower end by an anchor (12), such as hanger slips (121).

[0008] Fig. 2 shows an embodiment similar to Fig. 1 wherein an expandable portion (11) of the patch zone is about to be expanded above production zone (influx zone) Zl, by a drill pipe conveyed expander tool (81, 82). Having a sealing anchor in the bottom end of the patch (1) below the inflow production zone, and expanding the patch to a sealing zone to the liner (6) above the production zone will seal of the production zone. According to an embodiment of the invention the tracers are placed on the outer surface of the patch within this patch portion and will be sealed off as well. If those tracers are monitored in the production flow later on, a leakage from this zone is indicated.

[0009] Fig. 3 shows a shallow-perforating tool/canon (31), tool string/drill pipe conveyed, perforating the patch portion (111). Such a perforating tool may be carried as a separate trip operating tool or in another embodiment it will be assembled to the tool string carrying the expanding tool.

[0010] Fig. 4 illustrates a production situation after the tool string illustrated in Fig.3 is retracted and the well is producing again. The zonal flow Fzl producing through the perforations (3).

[0011] Fig. 5 shows a patch (1) with two patch zones ( l l li, I H2), marking and isolating two production zones (zl, z2), one each.

[0012] Fig. 6 illustrates different tailor made variations of the different patch zones (l l li) and how to utilize them. Zone zl has been sealed off by expanding an expandable area (11) in the total area of the inflow zone (zl). The invention is not limited by this figure, it rather illustrates that the tracer patch may be tailor made in a large number of combinations, depending on well design, production properties and other condition desires. The expandable portion (Hi) of the patch tubing (1) is arranged with tracers and a rubber seal. If those tracers are monitored in the production flow, a leakage from this zone is proven.

[0013] A patch zone may also be arranged with more perforated portions, as in the illustrated upper patch zone (I I I2). The main flow from the production zone (z2) will flow direct through the perforations and into the patch tube to the production flow (F) and a partial flow will flow in the second annulus A2 between the casing/liner (6) and the patch tube (1), pass the tracer source and flow into the production flow through a second perforated portion. A patch (1) may have several patch zones and the patch zones should be tailor made according to the well conditions and production desire.

[0014] Fig. 7a is an illustration of a patch (1) in a well with more patch zones (l l li, 1112, .. l l li) with different designs. Instead of an expandable portion forming a zonal zeal here a packer (50) is forming a zonal seal ( 131 i) . Such packer element may also work as an anchor (12). The middle patch portion leveled at the middle production zone (z2) may comprise an expandable patch portion (I I2) and can be used for sealing off the production zone upon desire, i.e. when water breakthrough is observed by monitoring water released tracers for the tracer source T2 or a combination of other observed tracer responses. The lower patch zone (l l li) is in this illustration sealing off a production zone by the expandable portion of the patch and may also serve as the anchoring device (12).

[0015] Fig. 7b is an illustration of another design with inward vented carrier (T2, tracer source) version. This inward vented option will monitor all flow from upstream its own location.

[0016] The section with inward vented carrier may or may not be expandable, but the sections both above and below can be expandable to isolate zones.

[0017] Fig. 8 illustrated an embodiment of the invention wherein the patch zones (l l li) comprises sliding sleeves (300) as flow valves for one or more flow zones. For production from a given zone they will be held open and when production from the zone is not desired they will be held closed. Operation of such sliding sleeves is known as such.

[0018] Fig. 9 This illustrates a combination of patch zones (l l li) comprising different tracer systems to monitor different closed zones and different sealing off systems. The sealing off can be done during installation or later, once unwanted fluids have been identified. For different tracer combinations, please see Fig. 15.

Fig. 10 is a rough sketch of a portion of a patch (1) in an embodiment of the invention, in a side elevation perspective and in a cross section cut A-A'. The figure shows an example of assembling a patch length with two different embodiments of patch portions (l l li, I I I2). According to the invention there are a plurality of possibilities for

combination of features within a patch portion and within a whole length of a patch (1). Fig. 11, 12 and 13 shows different arrangements of tracer sources, here polymer rods, with different embodiments of protective metal shroud put over the tracer system.

[0019] Fig 14 shows an embodiment of tracer arrangements to the patch with mechanical injection of tracers, and not just release from rods and filaments. Here shown a carrier with 12 cylindrical devices that each can inject a tracer volume at a preset point in time. The installation of tracer sources such as rods and filaments are known in the industry as such.

[0020] Fig. 15 shows a table of how different tracers (Tl...Ti) with different properties may be combined for different tracer sources for placing downhole the well at desired positions along a production tubing. Tw - affinity or releasable to water, To - affinity or releasable to oil. Combination with tracers designed for gas may also be used but is not illustrated in the table.

Embodiments of the invention

[0021] The invention will in the following be described and embodiments of the invention will be explained with reference to the accompanying drawings.

[0022] The invention is a method and a system for tracer marking and monitoring of a petroleum well with one or more production zones (zl, z2, ...) comprising placing tracers (Tr) at desired zones (zl, z2, ...) in a petroleum well with a production tubing (6), a casing or a liner with perforations (pi, p2, ...) at the zones ( zl, z2, ...) and comprising lowering one or more patch-tubes ( 1) into the well to a desired depth in a way that the one or more patch-tubes ( 1) extends into the production tubi ng (6) along on or more of the zones (zl, z2, ...) wherein the patch( l) is divided in one or more patch zones

(l l l i, l l l2, ... l l li) along the patch ( 1), wherein each patch zone ( 111 i) comprises one or more tracer sources (Τ1...ΤΪ) with one or more unique tracers (Trl ....Tri) arranged to release to produced fluids, such as oil, gas or water, in desired positions, one or more radial expandable patch portions ( l li, l l2, ... l li) arranged to be expanded, upon desire, to sealing against the tubing (6), anchoring an anchor ( 12) of the patch to the tubing (6), allowing the well to produce well fluids and monitoring the production flow (F) with respect to tracers.

[0023] Based on the monitoring result one will undertake actions in the well . Such actions may be none if the well has a satisfactory production . If for instance monitored tracers indicating a water breakthrough, one may choose to seal of the specific production zone identified by the unique tracers. The patch tube may be lowered into the well by a running in string tool, by a wire line or coi led tubing etc. and is known as such.

[0024] By tracer marking it should be understood to arrange tracers, at desired positions in a producing petroleum well, with tracer systems sources (Tl, T2, ...Ti) with corresponding unique tracers(tri, tr2, tr3, ...). Such tracers may be water, oil or gas releasable or another intelligent type such as releasable due to a chemical or physical change in conditions in the well, for release to the produced fluid . The tracers may also be baked into another material having such releasable properties and thus will be released to the prod uced flow on specific conditions as mentioned above or as a function of time. The tracers may be baked into polymer rods or polymer filaments. The tracers may also be mixed into epoxy and/or polymer solutions injections that cure in place. The tracers may also be released mechanically at given preprogrammed times or at desired times or given downhole conditions. Please see Fig . 14.

[0025] The monitoring may take place as a discrete sampling or by an online monitoring. Advantages to the method is that one may monitor which zones producing which fluids, both qualitatively and quantitatively. One will get information about and be able to evaluate god and/or bad producing zones. One may discover water intrusion, gas break through and be able to shut of the specific production zone, permanently or temporarily.

[0026] An advantage of the method is that one may install tracers into the tubing after the well has been completed . The tracers may also be installed after a time of production and based on information from well analysis carried out after a time of production, as well . This gives the possibility of very well designed tracer sources for placing at particular inflow zones etc. Another advantage is that one may seal of a production zone upon desire based upon information from the placed tracers during monitoring. A third advantage is that one may use the tracers as an integrity alarm for the seal sealing of the production zone. A fourth advantage is that one may form delay chambers for the tracers giving sharper tracer signals during monitoring. A fifth advantage is that both sealing elements and tracer monitoring elements may be installed in the well in the same operation, thus reducing operational time and cost.

[0027] In an embodiment of the invention the patch is anchored in a lower end of said patch (1). This is an advantage when it comes to use of an expansion tool. The patch is fixed downhole and free to move somewhat downstream, and the patch may be expanded on a later stage when retracting the tool without buckling ect.

[0028] In an embodiment one is anchoring the patch (1) by expanding one of said expandable patch portions (l li, l l2,... l li) wherein said expandable patch portion (l li, l l2,... l li) undergoes a plastic deformation and sealing against the tubing (6) forming an anchor (12). Using an expandable portion as the anchor facilitates a patch tube (1) with few complex components. Such an expandable portion will make a leak tight seal and a lower sealed end of a patch portion as an initial step of sealing a zone and direction the flow downstream and secure the zonal flow to pass a tracer source.

[0029] The expanding of said expandable patch portion (l li, l l2,... l li) is performed by an expansion pull tool (81) at a drill string (8) in an embodiment of the invention. A suitable tool is a tool for patching wells to repair hangers or to make joints and connections between casing and liner etc leak tight. Such a tool is described in

US20150218917.

[0030] In another embodiment the expanding of said expandable patch portion

(l li, l l2,... l li) is performed by an explosive expansion tool (82).

[0031] In an embodiment of the invention the anchoring of the patch (1) is executed by expanding hanger slips (121), comprised by said anchor (12), into the tubing (6). Such an anchor may not necessary be placed in a lower end of the patch and may also be set as a non sealing anchor as well as a sealing portion. This may be advantageous if one wish to anchor without sealing of the patch at the anchoring position. Preferably the anchors according to the embodiments are sealingly arranged. Hold down slips etc may then be used in an assembly with sealing packers to form a sealing anchor.

[0032] In an embodiment of the invention the anchor is forming a zonal sealing ( 131 i) between the patch (1) and the tubing (6) by setting said anchor (12) between two of said production zones (zl, z2,...) that separates different production zones marked with tracers by installing the patch which is tracer marked prior to lowering into the well.

[0033] According to an embodiment of the invention the patch (1) is arranged such that the one or more patch zones ( l l l i, l l l2, ... l l li) corresponds to each of the one or more production zones (zl, z2, ...zi) in the well . The different production zones have then been tracer marked and one may monitor the flow from the zones. The unique tracers may give information of production volumes and produced fluid .

[0034] One may in an embodiment of the invention set a zonal sealing ( 131 i) along the patch ( 1) between two or more of the production zones (Zl, Z2, ...Zi) by activating a sealing portion (50, Hi) in one or more of said patch zones (l l l i, l l l2, ... l l li) . Setting a sealing portion between the different production zones prevents the flow from one zone (e.g . zone 1) pass the tracer source arranged in a second production zone (e.g zon 2), thus releasing unique tracers from the second zone, which will give wrong information of zonal flow. Isolating the different tracers marked production zones enabling correct information about the different producing zones. By isolating zones by the packers or the patch in this way also one or more delay chambers ( 132i) has been formed . The zonal sealing ( 131 i) may be set both before and after the step of perforation. By setting a zeal in this way, without perforate, one may also seal of a zone if desired . The sealing portions may be of a general packer type, or a seal formed by an expandable portion being expanded .

[0035] The one or more patch portions ( 111 i) are arranged correlating to at least one production zones (zi) . A radial expandable patch ( 11), a sealing element (50) or a sealing anchor ( 12) is set both below and above the producing zone. The patch portion in between comprising at least one tracer source (Ti) with at least one tracer (Tri) and a portion (30) with, or arranged for, perforations (3), which forms the outlet for the fluid from the production zone. During a shut in this will work as a delay chamber and accumulate tracers within the chamber formed between the zonal seal sealing portions within the second annulus (A2) between the patch and the casing/liner (6) and when reopening of the well one will get a distinct tracer response that is easy to monitor. Figs. 2, 3, 4, 5, 7, 8 and 9 all illustrates embodiments that could form such a delay chamber. Fig . 8 could also form a delay chamber using the sliding sleeves instead of shut in the whole well .

[0036] In an embodiment of the invention the zonal sealing ( 131 i) is activated by expanding a portion ( H i) in the patch ( 1), by using an expansion tool (81,82), the portion ( H i) undergoes a plastic deformation, between two or more of the influx zones (zl, ...Zi) of the well, the expanding a portion ( H i) thus forming a zonal seal ( 131i) .

[0037] When using a patch ( 1) having more than one patch portions ( 11 li) there is no flow channel for the produced fluid into the production flow if a seal is set in both ends of the inflow zone in the casing or liner. Thus in an embodiment of the invention one will perforate the patch zones ( H l i, l l l2, ... l l li), by a shallow-perforating tool/canon (31) in one or more portions (30i) allowing produced fluid to flow through the resulting perforations (3) and into the patch tube. This may be performed during installation or on a later stage when for instance a patch portion is installed to seal off e.g. a zone with an undesired water cut and then on a later time one wish to reopen the zone to produce from the well with such water cut.

[0038] In an embodiment of the invention one may perforating the patch (1) prior to lowering the patch (1) in the well. This is an advantage when it comes to zones that should be producing and not sealed off. Then one do not have to lover a perforating canon into the well and the installation of the tracers and the well may produce as soon as the patch is installed by setting the anchors and the desired zonal seals.

[0039] In an embodiment of the method according to according to the invention the patch (1) is perforated above the tracer sources (Ti) within a patch zone ( 111 i) relative to said production zones (Zi) thus letting said produced fluid from said production zone (FZi) be in contact with said tracer sources (Ti) with said unique tracers (Tri) before flowing through said perforations (3). This forming an inflow path from the influx zone of the well passing the tracer source (Ti) with the one or more Tracers (Tri) into the patch (1) to the main production flow (F).

[0040] The method according to an embodiment of the invention letting the patch (1) be perforated at the same level as said production zones (Zi), and in the total length of the production zone. The tracer sources (Ti) is placed above said perforations within a patch zone ( 111 i) allowing a main flow of said produced fluid (Fzi) from said production zone (Zi) flow through the perforations and a partial flow of said produced fluid (Fi) from said production zone (Zi) be in contact with said tracer sources (Ti) with said unique tracers (Tri) before flowing through a second perforated portion (31i) with perforations (3) within said patch zone ( 111 i) . ) Please see Fig. 6 and upper part concerning patch portion 111 ₂ . This would allow the produced fluids to pass through the patch with a very minor pressure drop, and would "guide" a side-stream up the annular space formed by the patch. This would allow for stimulation jobs to reach the liner perforations very effectively, and would still offer monitoring functionality despite the potential erosion on the patch from the fluid inflow from the zones. The monitoring functionality would be mainly two-fold. Firstly, one would get a higher side-stream if the production from the perforations are larger, and thus one would be able to indicate high and low producing zones by the tracer response of the annular void if one balances the patch perforations correctly on both sides of the tracer systems (as indicated on the figure). Secondly one would still isolate the tracer systems in the annulus to some degree from fluids coming from upstream of the perforations in connection with the tracer system, and this will enhance water monitoring as one would not get fluids from upstream the tracer sources location coming in contact with the tracer sources.

[0041] According to an embodiment of the invented method one or more tracer sources (Ti) are placed outside one or more of said expandable patch portion (l li, l l2, ... l li) of said patch (1). This is the preferred arrangement for all marking of zonal flow. Tracers arranged at the outside of the patch may be part of the expandable patch portion, the perforated portion or be arranged at a separate portion of the patch.

[0042] In an embodiment of the invention, one may arrange tracers as inward vented, i.e. one or more tracer sources (Tl ...Ti) is arranged in one or more positions () on the inner wall (101) of the patch (1). This option will monitor all flow from upstream. The section with inward vented carrier may or may not be expandable, but the sections both above and below can be expandable to isolate zones. Please see Fig. 7b.

[0043] The method according an embodiment of the invention comprises to expand one or more of said expandable patch portion (l li, l l2,... l li) of said patch (1) in the total area of one or more influx zones (zi) to seal off and stop the flow from the sealed off zone (zi). Preferably, here this patch area has a sealing layer (of rubber etc) outside the expandable area. This gives an opportunity to seal off a production zone when installing the patch, based on production information available, or to zeal of the zone after monitoring the producing well with an installed tracer patch according to the invention. When tracers are arranged inside this sealing patch portion as described above continued monitoring will give information about the integrity of the seal. When no tracers unique for this zone is monitored one may assume that the zeal is tightfitting and well working.

[0044] If the tracers unique for a specific sealed/shut off zone is monitored one may assume the seal is not working or there might be a cross flow from this zone to another inflow opening to the production flow.

[0045] In an embodiment of the invention the patch is expanded as a result of a monitored occurrence (O) in the well, i.e. types of observations and how they may be observed, both based on the patch installed tracers, their analysis, or another way. A typical situation would be that one zone is indicated to produce water by observing a combination of the oil, water and/or gas tracers, or one zone is found to produce gas by the same observation. Both these may be undesired fluids relative to oil, and there may be motivation for shutting the zone off. Indications of water may be the increased presence of water tracer and the reduced presence of oil tracer from a zone, and indications of gas may be the simultaneous reduction of both oil and water tracers from a zone as this may not trigger oil nor water tracer release or the observation of an increased gas tracer.

[0046] According to an embodiment of the invention an inflow path for a zonal inflow (Fi) through the patch (1) is activated by activating a valve system (112) arranged in a patch zone (l l li), such as sliding sleeves etc. Thus forming an inflow path from the influx zone of the well, passing the tracer source (Ti) with the one or more Tracers (Tri), into the patch (1) to the main production flow (F). This is an advantage due to the fact that sliding sleeves may be operated from for instance an open position when the zonal production is satisfactory, to a closed position when the production becomes

unsatisfactory, such as water break through etc. It is also possible to reopen the sliding sleeves to make the zone produce again, or vice versa, without the need of a perforation gun/canon. .

[0047] The method according to an embodiment comprises that two or more patches (1) is lowered into the well to different desired depths of the well. This will cover influx zones separated by a long distance of hard rock or another formation, generally without any influx zones and no need for tracer marking. It is economical unfavorable to have a several hundred meters long patch when there is no production in for instance the major area.

A method according to an embodiment of the invention a production zone has been sealed by expanding the patch over an inflowing zone (zi) or by setting a sealing portion, for example by setting a packer or expand a patch portion, in both ends of the producing zone, according to embodiments described above. After a time of production it may be of interest to produce from that zone again and the patch in the production zone may then zone (zl,z2...zi) be reopened by a the use of a perforating canon, and the zone will produce again. The tracers attached to the patch will become in contact with the zonal production, release to the flow, and the monitoring the unique tracers from this zone will confirm that the zone is open, producing and what kind of fluid is producing.

[0048] The invention also is a system for arranging tracers inside a tube (6), such as inside a liner or casing, in petroleum (hydrocarbon) well comprising a length of a tube formed patch (1) with outer diameter less than an inner diameter of the tube (6), wherein the patch (1) is divided in one or more patch zones (l l li, l l l2,... l l li) along the patch (1);

wherein each patch zone (l l li) comprises

- one or more tracer sources (Tl ...Ti) with one or more tracers (Trl ....Tri)

- one or more radial expandable patch portions (l li, l l2,... l li).

[0049] The patch length will in general be made of one base material, such as a metal tube, and have properties allowing the patch to be expanded and undergo a plastic deformation. Reinforced portions or an assembled patch length may be used for special design as dicussed below.

[0050] Advantage to the system is that it is a system enabling retrofit installation into a well without, with wrong, or with empty tracer sources. The tracer patch system should be tailor made to the specific well that it will be installed into. Another advantage is that the radial expandable portions may be used to seal of a production zone upon desire. The expandable portion can also be used to isolate inflow zones from each other.

[0051] In an embodiment of the invention the one or more of said patch zones (l l li) is arranged for perforations (3) through the patch wall (110) in at least a portion (30).

[0052] In an embodiment of the tracer arranging system according to according to the invention at least one portion (30) is pre perforated (3). Which means the patch is perforated before it is lowered into the well, which may exclude or limit the use of a shallow perforating gun/canon.

[0053] According to an embodiment of the invention one or more of the one or more tracer sources (Ti) is arranged on the outer wall (102) of the patch (1).

[0054] The tracer arranging system according to the invention comprises at least one anchoring device (11, 12) for anchoring the patch (1) to the tube (6). Such an anchor may be radially expandable patch portion, a packer device or a hanger slips type device.

[0055] In an embodiment of system according to claim 23, wherein the anchoring device is located near an end of the patch (1).

[0056] In an embodiment of the tracer installation system the portion with perforations

(3) or the portion (30) arranged for perforations (3), the tracer sources (Tl ...Ti) and the radial expandable portion (11) is arranged adjacent/next to each other.

[0057] In another embodiment of the tracer installation system the tracer sources

(Tl...Ti) and the radial expandable portion (11) is arranged in the same portion of the patch.

[0058] In an embodiment of the invention the portion (30) is arranged to be perforated by a shallow penetrating perforation canon (31). Such canon may be lowered into and operated by a tool string device etc. It may be a separate tool which may be ran in separately or it may be a combined tool, combined with any other tools such as setting tools or the mentioned expansion tool used by this invention.

[0059] According to an embodiment of the invention the tracer arranging system comprises a zonal sealing element (50) in one or more of the one or more patch zones (l l li). Any kind of packer or sealing element that can be built into a patch and set and activated to a leak tight seal between the patch and the well tubing, liner, casing or the like may be used . The sealing element has the advantage that it may be used to seal between zones or to shut off a zone. The sealing element may also be used as a hanger (12) or anchoring solution.

[0060] In an embodiment of the invention a protecting layer (4) is arranged outside the tracer sources (Ti) in order to prevented the tracer sources from being ripped off during installation of the patch (1) into the well. Such protecting layer may be a mesh (41) or a thin metal shroud or pipe holster/jacket (42). The mesh and the holster may be formed of metal or a flexible material that may undergo an expansion so as for being a part of the radial expandable portion but other non elastic or flexible material may also be used for embodiments where the portion with the tracers should not be expanded. Please see examples in illustration Figs. 11 - 13.

In an embodiment according to the invention the patch (1) comprises a partly or fully enveloping sealing material (13) arranged on its outer wall (102). A sealing material can also be used as a protecting layer, such as for instance a rubber layer that is arranged on the outer surface of the patch (portion) the layer may be partly or fully enveloping the circumference of the patch. Tracer sources formed as e.g. polymer rods may be placed in elongated grooves or slots in the sealing layer along the elongated slots along the enveloping sealing material (13), or the rubber material may be formed holster like. Please see Fig. 10.

Other design of polymer carrier for the tracers could be used, such as ring formed, plate formed etc.

[0061] In an embodiment the partly or total enveloping sealing material (13) in one or more portions of the enveloping part forms a totally enveloping circumferential seal that will seal to the casing or liner (6) in a closely, firmly and leak tight manner. Then this material will work as a seal, a packer and/or even as an anchor (12) for the patch (1). In an embodiment tracers and sealing material forms part of a radial expandable patch portion (Hi) and will be able to form a leak tight shut off of a production zone (Zi) with a tracer alarm system for integrity of the seal.

[0062] In an embodiment of the tracer arranging system according to the invention a patch zone ( 111 i) comprises open and lockable flow through areas (300) such as sliding sleeves etc. Please see Fig. 8.

[0063] In an embodiment of the tracer arranging system according to the invention a patch zone ( 111 i) comprises two portions with perforations (3) or portions (30) arranged for perforations (3) with one or more tracer sources (Ti) in between. Please see Fig. 6, upper section.

[0064] According to an embodiment of the tracer arranging system at least one patch zone comprises at least a sealing portion (11,50) arranged in both ends of the patch zone to seal of a production zone (Zi).

In an embodiment of the invention the tracer arranging system comprises at least one reinforced tube portion (60) in one or more patch zones (l l li). When the blank (non- perforated) patch is placed over the perforations in the cemented liner that is the patch may be exposed to erosion and this may "burn" though the patch making a perforation in a relatively short period of time and thus harm the monitoring system. A reinforced portion will make the patch more robust over the producing interval(s) so that it can stand the jets coming from the producing perforations. Reinforcing could be done by adding "blast-joints" to the patch, which in essence is thick pipe of a robust material, or one there may be arranged ceramic piping over the interval that would not erode.

[0065] The invention is also the use of the method and the device according to the described embodiments also comprising gather information about production and design of a producing petroleum well, tailor make a patch (1) according to the tracer placing system described, and the well design of the well to be monitored, and production properties for the desired well and then marking, monitoring and acting according to method described above.

[0066] Another embodiment of the invention is a method and a system for tracer marking and monitoring of a petroleum well with one or more production zones (zl, z2, ...) comprising placing tracers (Tr) at desired zones (zl, z2, ...) in a petroleum well with a production tubing (6), a casing or a liner with perforations (pi, p2, ...) at the zones ( zl, z2, ...) and comprising lowering one or more patch-tubes (1) into the well to a desired depth in a way that the one or more patch-tubes (1) extends into the production tubing (6) along on or more of the zones (zl, z2,...) wherein the patch(l) is divided in one or more patch zones (l l li, l l l2,... l l li) along the patch (1), wherein each patch zone ( 111 i ) comprises

one or more tracer sources (Τ1...ΤΪ) with one or more unique tracers (Trl ....Tri) arranged to release to produced fluids, in desired positions, one or more radial expandable packers (50) arranged to be expanded, upon desire, to sealing against the tubing (6), anchoring an anchor (12) of the patch to the tubing (6), allowing the well to produce well fluids and monitoring the production flow (F) with respect to tracers.

[0067] Based on the monitoring result one will undertake actions in the well. Such actions may be non if the well has a satisfactory production. If for instance monitored tracers indicating a water breakthrough, one may choose to seal of the specific production zone identified by the unique tracers. The patch tube may be lowered into the well by a running in string tool, by a wire line or coiled tubing etc. and is known as such.

[0068] In this aspect of the invention the patch does not have the expandable portions. The patch may be a metal blank or another tube or liner suitable for arranging into a producing petroleum well. This is a more simple way of retrofit installation of tracers and utilize all the features and advantages of the first aspect that does not require the expandable portions. I.e for instance sealing off is performed by packers and anchoring by packers or hanger slips.