METHOD AND SYSTEM FOR ENABLING AT SURFACE CORE ORIENTATION DATA TRANSFER
20230167737 · 2023-06-01
Inventors
Cpc classification
E21B25/005
FIXED CONSTRUCTIONS
E21B47/26
FIXED CONSTRUCTIONS
International classification
E21B47/09
FIXED CONSTRUCTIONS
E21B25/00
FIXED CONSTRUCTIONS
Abstract
A contactless orientation system coupled with an inner core tube to one or more record carriers on or associated with a core sample held in the core tube having a longitudinal core axis and a core face accessible from an end of the inner core tube. An instrument guide is coupled to the end of the core tube from which the core face is accessible with an axis of the guide parallel to the core axis. Correlation information is generated between a rotational orientation of a known point P on the instrument guide about the guide axis and core orientation data known to the contactless orientation system. The instrument acts as the record carrier or generates the record carrier provided with the correlation information enabling orientation of the core sample to its in-situ orientation when released from the core tube.
Claims
1. A method of enabling at surface orientation data transfer from a contactless orientation system coupled with an inner core tube to one or more record carriers on or associated with a core sample held in the core tube, the core sample having a longitudinal core axis and a core face accessible from an end of the inner core tube, the method comprising: when the inner core tube is at the surface, coupling an instrument guide having a guide axis to the end of the core tube from which the core face is accessible and opposite the contactless orientation system wherein the guide axis is parallel to the core axis; generating correlation information between a rotational orientation of a known point on the instrument guide or an instrument supported by the instrument guide about the guide axis with core orientation data known to the contactless orientation system; and using the instrument to: act as the record carrier; or generate the record carrier provided with the correlation information enabling orientation of the core sample to its in-situ orientation when released from the core tube.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0052] Notwithstanding any other forms which may fall within the scope of the method and system as sets forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:
[0053]
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[0055]
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DETAILED DESCRIPTION
[0063]
[0064] This embodiment of the system 10 comprises an instrument guide 20 having a first end 22 and an opposite end 24 that are or can be arranged to lie on a common guide axis 26. The guide axis 26 is parallel to the core axis 16. The instrument guide 20 is configured so that when the first end 22 is coupled or otherwise engaged with the core tube 12, the core face 18 lies between the first and second end 22 and 24. This is shown for example in present
[0065] The system 10 also includes an instrument 28a (
[0066] Individual components and parts of the system 10 will now be described in greater detail.
[0067] The instrument guide 20 is composed of a first sleeve 30 and a second sleeve 32. The sleeves 30 and 32 are releasably connectable together. In this example this is by way of complementary screw threads 34a and 34b. The first sleeve 30 is formed with an inner diameter which is slightly larger than the outer diameter of the core tube 12. This enables the instrument guide 20 to engage the core tube 12 with minimal radial play. A number of viewing ports 36 are formed in the sleeve 30 near an end at which the sleeve 30 couples to the sleeve 32. Sleeve 32 houses the instrument 28a. The instrument 28a is keyed to the sleeve 32 so that it has a known rotational orientation with reference to one or more known reference point P1, P2 . . . Pn (hereinafter referee to in general as known point(s) P), of the system. This is achieved by way of engagement of the instrument 28a with mounting pin 38 provided with the sleeve 32. The instrument 28a and the mounting pin 38 are arranged so that the instrument 28a can lock into the sleeve 32 on the mounting pin 38 in only one specific and known orientation about the guide axis 26.
[0068] The system 10 has a rotational position sensor 40, in this example a spirit level 41, to provide an operator with information relating to the rotational position of the known point(s) P of the system 10 about the guide axis 26. The point P maybe one of a plurality of known points P1, P2 etc. Further the one or more points P may be either on or referable to the guide 20 or the instrument 28a supported by the guide.
[0069] In this instance the sensor 40 is attached to the instrument guide 20 near the end 24 of the sleeve 32. The system 10 is also provided with an axial passage 42 which is parallel with the axis 26. The passage 42 opens onto the end 24. The passage 42 is provided to enable receipt of a second or alternative instrument 28b in the form of a china pencil (see
[0070] The instrument 28a has a core face profile recording system 44 which comprises a set of pins 46 and a marker in the form of a pencil 48. The pins 46 are frictionally retained within a body 50 of the instrument 28a and are able to slide lineally in a direction parallel to the guide axis 26. An outer surface 52 of the body 50 is provided with a compass or bearing scale 54 (see
[0071] One such point P1 may be the rotational position of the marker 48 of the instrument 28a about the guide axis 26. An alternate or additional point P2 may be the rotational position of the axis of the passage 42 about position of the guide axis 26. In this particular embodiment both of these points P1 and P2 lie on the same radius of the guide axis 26. That is, the points P1 and P2 have the same rotational position about the guide axis 26.
[0072] The instrument 28a also includes a demountable cap 56 (see
[0073] The cap 56 is also provided with a surface 58 which can be manually marked for example by an indelible marker with header data relating to the core sample. Header data may include: identification data (e.g. a hole number) of the hole from which the core sample 18 is obtained; the driller ID; and the depth of hole at which the sample was extracted. Further details of the instrument 28a may be obtained from US publication number 2010/0230165 the contents of which is incorporated herein by way of reference.
[0074] A method 100 of using the above described embodiment of the system 10 for enabling at surface core orientation data transfer will now be described.
[0075]
[0076] This embodiment of the method 100 can be considered as involving three broad steps namely:
Step 102: coupling the instrument guide 20 to the end of the core tube 12 from which the core face 18 is accessible so that the guide axis 26 is parallel to the core axis 16;
Step 104: generating correlation information between a rotational orientation of a known point P on the instrument guide 20 or an instrument 28a supported by the instrument guide 20 about the guide axis 26 and core orientation data known to the contactless orientation system; and
Step 106: using or otherwise operating the instrument 28a to: act as the record carrier; or generate the record carrier provided with the correlation information enabling orientation of the core sample 14 to its in-situ orientation when released from the core tube 12.
[0077] As described below the generation of the correlation information between the positions of the known point P and the core orientation data may be via a common reference point A.
[0078] With reference to the presently described embodiment of the system 10, the step 102 of coupling the instrument guide 20 to the end of the core tube 12 is achieved by mounting or otherwise arranging the instrument guide 20 relative to the core sample 14 so that the core face 18 lies between the first and second end 22 and 24 of the instrument guide 20. The end 22 of the guide 20 is simply slid onto and over the core sample 14 and the adjacent portion of the inner core tube 12. This arrangement is shown specifically in
[0079]
the gravitational bottom of the hole, this is particularly suitable for inclined holes;
magnetic north; or
True north.
[0080] When retrieving the core sample 14 from a drill string and subsequently placing the corresponding core tube 12 on a core table or jig the relative rotational position of the contactless core orientation system 11 and the core sample 14 have not changed. Also the contactless core orientation system 11 by its very nature is able to detect the known reference when at the surface or in the hole.
[0081] In this embodiment we will assume that the contactless orientation system 11 logs orientation data of the a point on the core 14 relative to bottom dead centre of the bore hole rather than magnetic north or true north.
[0082]
[0083] The guide 20 is not coupled to the core tube 12 at this time. The in situ gravitational bottom of hole location BH of the core sample 14, while known to the contactless core orientation system 11 is at a random rotational position about the axis 16. In the present example the point BH is at a bearing of about 300° (or −60°) about the axis 16.
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[0086] An operator will now rotate the instrument 20 relative to the core tube 16 to level the position of the bubble in the spirit level 40. During this process the core sample 14 and core 12 remain rotationally stationary. This will result in the marker 48 being rotated to coincide with the common reference point A at the 180° bearing location. This is also the current physical rotational location position of the point BH. The relative positions of the core sample 12 and the instrument guide 20/instrument 28a upon completion of this process is shown in
[0087] Therefore by the above process the location of point P/marker 48 has been correlated with or referenced to the in situ rotational position BH of the core sample. This process has generated correlation data being that the known point P now has the same rotational position about the axes 16, 26 as the point BH. (In another example shown later the correlation data is that the known point P is at a known rotational offset from the point BH.)
[0088] The instrument 28a is now operated (in this case by using the guide 20 to slide the instrument 28a into contact with the face 18), to generate the record carrier provided with the correlation information. Indeed in this example two record carriers are generated. One record carrier 20 is the core 14 while a second independent record carrier is the instrument 28a.
[0089] Specifically operating instrument 28a in this example involves an operator using the guide 20 to move the instrument 28a into contact with the face 18. This will result in a linear translation of the pins 46 in accordance with the profile of the face 18 as well as the marker pencil 48 placing a physical mark TD on the core face 14 with the pencil tip 60. This is exemplified in
[0090] The core face 18 bearing the mark TD now constitutes a first record carrier of the in situ orientation data of the core sample 14. The mark TD is or otherwise constitutes the transferred orientation data from the contactless orientation system 11 to the record carrier. Thus the point TD is indicative of the orientation of the known point P and corresponds to or has a known relationship with the in situ orientation of the core sample 14. In this specific embodiment the rotational position of the mark TD is the same as the orientation of the known point P. However in other embodiments transferred orientation data TD is not a physical mark on the core sample 14 but rather electronically storable data which provides an indication of the in situ orientation of the core sample 14.
[0091] The instrument 28a, by virtue of the pins 46 and either the pencil 48 or the hole in which the pencil 48 is held, forms or acts as another independent record carrier bearing correlation information enabling orientation of the core sample 14 to its in situ orientation when released from the core tube 12. By keeping the instrument 28a with the core sample 14 a geologist can always properly orientate the core sample 14 by matching the profile of the face 18 with the profile of the pins 46 and then rotating/rolling the instrument 28a with the core sample 14 in a horizontal plane so that the location pencil 48 is a bearing of 180°. When at the 180° bearing the geologist knows that the lowermost point of the core 14 corresponds with the point BH recorded by the system 11. Therefore even if the mark TD on the core face 18 has been lost the core sample 14 can still be placed in its in situ orientation.
[0092] The instrument 28a can be removed from the guide 20 by decoupling the sleeves 22 and 24 from each other and pulling the instrument 28a off of its mounting key 38. The cap 56 may then be attached to the body 50 to protect the pins 46 form accidental displacement. Header data can be manually written onto the surface 58 of the cap 56. The instrument 28a is retained with the core sample 12. Thus a new instrument 28a is required for each orientation data transfer.
[0093] The above position procedure for generating the correlation information or otherwise referencing the in situ core orientation for known point P of the system 10 could also be used for vertical boreholes that do not have a gravitational bottom of hole reference position. This requires the use of a contactless orientation system that relies on magnetic north or true north as the known (detectable) reference point.
Lower Cost Embodiment
[0094] In this variation, depicted in
[0095] In Brief
[0096] the core sample 12 is rotated until the system 11 indicates that the bottom of hole location BH is at the 180° bearing location
[0097] the guide 20 is fitted onto the core tube 12 and rotated relative to the core tube 12 about the axis 26 until the axis of the passage 42 is also at the 180° bearing location as indicated by the spirit level/sensor 40.
[0098] The instrument/pencil 28b is inserted into the passage 42 and pushed into contact with the core face 18 leaving a gravitational bottom of hole, true or magnetic north core orientation mark P on the core face 18 in a manner identical to that described above in relation to the instrument/pencil 28b. Therefore instead of the guide 20 being physically moved in order to achieve contact, the instrument 28b is moved being guided by the passage 42 of the guide 20. The only record carrier in this instance is the core face 18/core 14 itself. There is no separate record carrier as described in the first embodiment.
Electronic Memory Embodiment
[0099] In a further variation, the instrument 28a may be provided with an electronic memory device 74 (shown schematically in
[0100] The time and date of moving the instrument 28a in a direction parallel to the core axis 16 to contact the core face 18.
[0101] The geographical location at which the present method is performed. This may be the way of use of GPS data sourced from the contactless orientation system or indeed from a GPS system also embedded within the guide 20 or the instrument 28a.
[0102] A degree and direction of rotation of the instrument guide 20 relative to the core tube 12 about the core axis 16 and/or the actual true core orientation position in the time period when the guide system 10 is being used to move the instrument 28 relative to the core face 14 to cause contact between the core face and the instrument.
[0103] Tool face of the core sample 14.
[0104] In order to enable recording of data (c) above, embodiments of the system 10 may also be provided with one or more accelerometers to detect rotational motion about the axis 26. Ideally such GPS and other digital, magnetic or gyroscopic devices will be placed in the guide 20 rather than the instrument 28a to reduce the overall cost of the consumable product namely, the instrument 28a.
[0105] The instrument 28a in this embodiment is used in exactly the same manner as described above in relation to the first embodiment of the additional step of electronically transferring information from one, or any combination, of: the system 11; the GPS and other digital, magnetic or gyroscopic device in the guide 20; or other instrument such as smart phone. For example the smart phone may be used to enter some or all of the audit data into the electronic memory.
Electronic Generation of Correlation Information (or Rotational Position Referencing) Embodiment
[0106]
[0107] The method 100 of referencing the position of point BH to the point P and the subsequent creation of the record carrier bearing the point P is described in more detail below with reference to
[0108] The method 100 entails, once the core sample 14 and core tube 12 are placed on a core table or rack, with point A representing the lowest rotational position of the core sample 14 on the table, i.e. the 180° bearing position:
operating the system 11 to log the position A and therefore determine the rotational offset (e.g. α°=125°) of the point BH to the point A (it should be understood that point A is not marked on the core sample 14);
operate the system 41′ to determine the rotational position of point P relative to the point A, (e.g. β°=260°, the rotational position of point P being coincident with a known point on the guide 20 such as the axis of passage 42, or the rotational orientation of the instrument 28a held within the guide 20, at this time the point TD has not been marked on the core sample 14);
transfer the offset α° to the system 41′, or transfer the offset β° to the system 11; using a processor in either the system 11, or in the system 41′, to calculate the rotational offset (θ°=β°−α°=135°) between the points BH and P;
transfer the offset θ° to the electronic memory.
[0109] The guide 20 can now be used to cause contact between the instrument 28a and the core face 14 thereby physically marking the core face 14 with the point TD. Alternately one can first affect the contact between the core face 18 and the instrument 28a to mark the core face 18 with the mark TD and at that time, before separation, electronically reference the location of point P to the point BH. This then removes the possibility of an error being generated by unintended rotation of the guide 20 when performing the contact. It should be noted that in this embodiment there is no need to rotate the guide 20 in order that the point P rotationally coincides with the point A. This is because the offset θ° is now known and recorded. Thus a geologist by accessing a database associated with the core sample 14 knows of the physical point P is offset by θ° degrees from the reference point (in this case gravitational bottom of the hole). The geologist now rotates the core sample 14 about a horizontal axis so that the point P is in the rotational offset position, at which time the core sample 14 will be in its in situ orientation at the time of the core breaking operation.
[0110] This embodiment of system 10 requires that the contactless orientation system 11 and the system 41′ are able to communicate to each other the bearing of their respective points BH and P. Either one of the systems 11 or 41′ can then determine the position of point P relative to the gravitational bottom of hole, magnetic or true north directional location BH. This is communicated to an electronic memory 74 in or on the instrument 28a either by the system 11 or the system 41′.
[0111] Providing WiFi capability in either the system 11, system 41′ or indeed the memory 74 also enables header and/or audit data inclusive of course of core orientation data to be automatically uploaded to a centralised data management system or hub. This then enables a geologist to simply access the database and view the information stored in relation to any particular core sample to enable access to auditable data pertaining to the orientation of the core sample.
[0112] Contactless Orientation Data Transfer Embodiment
[0113] In an extension or refinement of the system 10′ shown in
[0114] The image capture device is arranged so that the point P can be designated at a specific pixel on an image of the core face 18. This pixel appears in a known manner for, example a cross, on the image. The image capture device (i.e. the instrument) may itself have an inbuilt orientation system which knows and stores information relating to the orientation of the point P about a known reference such as the 180° bearing about a horizontal axis, true North or magnetic north. Alternately the instrument guide 20 supporting instrument 28a may have an electronic rotational orientation system 41′ as described above which can communicate orientation information to the image capture device.
[0115] Since the instrument 11 knows the in situ orientation data the correlation information relating the rotational position of this point P with or to point BH can be generated as described above in relation to the embodiment in
[0116] Whilst a number of specific method and system embodiments have been described, it should be appreciated that the method and system may be embodied in many other forms.
[0117] For example, the record carrier incorporated in the system 10 shown in
[0118] In yet a further variation a camera may be provided in the instrument 28a described with reference to
[0119] In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” and variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the system and method as disclosed herein.