AU722965B2

AU722965B2 - Drill core measurement means

Info

Publication number: AU722965B2
Application number: AU48525/97A
Authority: AU
Inventors: Stewart Stretch
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-12-20
Filing date: 1997-12-19
Publication date: 2000-08-17
Anticipated expiration: 2017-12-19
Also published as: AU4852597A

Description

1, il P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT

C

*SSSS

Name of Applicant: Actual Inventor(s): Address for service is: Stewart Stretch Stewart Stretch WRAY ASSOCIATES 239 Adelaide Terrace Perth, WA 6000 Attorney code: WR Invention Title: "Drill Core Measurement Means" Details of Associated Provisional Application No(s): P04303 The following statement is a full description of this invention, including the best method of performing it known to me:- 2 The present invention relates to a measuring means which can be utilised in analysing a core sample of a drill core.

In exploration drilling it is necessary to analyse the resultant drill core in order to determine the existence of any relevant geological structures which may be of significance in determining the presence of an ore body and the analysis of such core sample can also be used to determine the magnitude of that ore body. To make this determination requires an accurate analysis of the core sample relative to the position in the ground from which it was taken.

It is an object of the present invention to provide a support arrangement for a core sample which can reposition that core sample in space at a position which substantially corresponds to the attitude at which it was originally located in the :.":ground in order to facilitate the analysis of the features which are exhibited by "the core sample.

Accordingly the invention resides in a drill core measuring means comprising a S. 15 base, a first support rotatably supported from the base for rotation about a substantially upright first axis, a cradle adapted to support a core sample, the :cradle being pivotally supported from the first support about a second axis which is substantially perpendicular to the first axis, the intersection of the first axis and the second axis corresponding to the intersection of the first axis and the S 20 central axis of a core sample accommodated by the cradle, a cursor supported from a second support which is rotatably supported from the base for rotation about the first axis, said cursor being supported from the second support to be rotatable about a third axis perpendicular to the first axis said cursor defining a reference plane which intersects the third axis.

According to a preferred feature of the invention the position of the cursor is displaceable on the second support in a direction substantially parallel to the first axis.

According to a preferred feature of the invention a first scale is provided between the base and the first support to provide a measure of relative angular displacement therebetween about the first axis.

According to a further preferred feature a second scale is provided between the cradle and the first support to provide a measure of the relative angular displacement therebetween about the second axis.

According to a further preferred feature of the invention a third scale is provided between the second support and base to provide a measure of the relative angular displacement therebetween about the first axis.

10 According to a further preferred feature of the invention a fourth scale is provided between the cursor and the second support to provide a measure of the angular displacement therebetween about the third axis.

According to a preferred feature of the invention the first and third scales incorporate the points of the Compass.

According to a further preferred feature the first and third scale comprise the same scale.

II..i The invention will be more fully understood in the light of the following description of one specific embodiment. The description is made with reference to the accompanying drawings of which: Figure 1 is a perspective view of a drill core measuring tool according to the embodiment; Figure 2 is plan view of the drill core measuring tool of the embodiment,.

The embodiment comprises a tool which can be utilised in analysing the features present in a core sample. The tool comprises a base 11 which is intended to be substantially positioned such that it is substantially horizontal.

The base supports a first support 12 which comprises a circular first turntable 13 which is rotatably supported on the base' about a central axis of the base 11 and which supports an upstanding post member 14. The first support 12 is provided with a locknut 15 which provides the pivot axis for the turntable 13 on the base 11.

The first turntable 13 supports an upstanding post member 14 which in turn supports a cradle 16 which is configured to be able to support a core sample C.

The cradle 16 is rotatably supported from the post 14 about a second axis which is perpendicular to the first axis about which the first support 12 rotates where the intersection of the second axis with the first axis corresponds with the intersection of the first axis with the central axis of the core sample C accommodated within the cradle 16. A second locknut 17 is associated with the rotatable mounting of the cradle 16 to facilitate the locking of the cradle 16 in *position with respect to the post 14.

The cradle 16 is provided with a clamping means 18 which is able to clampingly retain the core sample C in position on the cradle 16. The clamping means comprises an upper bracket 19 which is intended to overly core sample C and which is provided with a central reference sighting wire 20 which is located such that it lies within the vertical plane which accommodates the first axis and the central longitudinal axis of the core sample C supported in the cradle 16. In use it is intended that the sighting wire 20 will be aligned with a marking provided on the core sample indicating the upper surface of the core sample C when the core sample is extracted from the bore hole. As a result the core sample C is able to be positioned in the cradle 16 such that its orientation about its central axis will correspond substantially with the orientation that the core sample had prior to its extraction from the ground.

In determining the position that the core sample should occupy in space it is necessary to refer to the logging data which is provided with the core sample and which provides information regarding the position of the drilling tool at the time the core sample was extracted. By rotation of the first turntable 13 about the first axis the core sample C can be located in a position corresponding with the azimuth of the hole at the location from which it was extracted. In addition the rotation of the cradle 16 about the second axis enables the core sample to be positioned at an angle corresponding to the angle of elevation of the hole at the position from which the core sample C has been extracted. Therefore by utilisation of the mounting of first support and the cradle from the base 11 the core sample can be positioned in a position in space which corresponds with the attitude that the core sample occupied in the ground from which it was extracted.

The instrument further comprises an upstanding support 21 which is mounted to a circular second turntable 22 which is also rotatable about the first axis and which is concentric with the first turntable 13 but is of a greater diameter. The first locknut 15 is mounted such that it is isolated in its action to be able to only lock the first turntable, whereby when it has locked the first turntable in position S the second turntable is still capable of being caused to rotate on the base to 15 occupy any desired position on the base. The upstanding support 21 slidably supports a mounting 23 which is capable of displacement along an axis perpendicular to the base 11 and which is associated with a clamping means (not shown) associated with a third locknut 24 whereby the mounting 23 can be positioned at any position along the support 21. The mounting 23 comprises a circular front plate which rotatably supports a cursor 25 through a hub 27 which is rotatably mounted on the circular plate about a third axis which is perpendicular to the first axis and which intersects the first axis. As a result of the capacity of the mounting 23 to be displaced perpendicularly from the base 11 the point of intersection with the third axis can also be displaced vertically along the first axis. The cursor 25 comprises a U-shaped member where one arm 28 is slidably receivable in the hub 27. The other arm of the cursor 25 is parallel to the one arm 28 and the web 30 is parallel to the third axis. The arms 28 and 29 of the cursor intersect with the third axis and as a result the cursor defines a reference plane which intersects the third axis. The engagement between the one arm 28 of the cursor 25 and the hub 27 is such that the arm 28 is frictionally retained in the hub and will be held in position as a result of such frictional engagement but is capable of slidable displacement in the hub on the 6 application of a suitable force. The orientation of the cursor 25 is such that the third axis is coplanar with the plane occupied by the arms 28 and 29 and web of the cursor 25. The mounting of the cursor 25 to the base through the second turntable 22 and the hub 27 enables the cursor to be positioned such that its plane corresponds with the plane occupied by a boundary of a geological feature that may be observed as being present in the core sample C.

The base 11 is provided with a first scale 31 which is concentric with the first axis and which surrounds the perimeter of the second turntable 22. The first scale corresponds to the points of the Compass. In addition the first turntable 13 is provided a first reference pointer 32 which has a reference axis which is coplanar with the plane occupied by the central axis of the core sample C accommodated within the cradle 16 whereby the first turntable 13 can be positioned relative to the first scale 31 at a position corresponding to the azimuth of the hole from which the core sample has been extracted.

15 In addition the cradle 16 is provided with a part circular scale second scale 33 which is associated with a second pointer 34 supported from the first turntable 0 13. The relationship between the second scale 33 and the second pointer 34 enables the angle of the cradle relative to the horizontal or vertical axis to be readily determined in order that the core sample C can be positioned at an angle which corresponds to the angle of depression and angle of elevation of core hole at the position from which the core sample C was extracted.

The second turntable 22 is provided with a pair of perpendicularly disposed reference pointers which comprise a third reference pointer 35 and a fourth reference pointer 36 where the reference pointers are disposed at 900 with respect to each other. The first reference pointer 35 is intended to provide an indication of the azimuth of the dip direction of the boundary of discontinuity detected in the core sample C and with which the cursor 25 is aligned while the fourth reference pointer 36 is intended to provide an indication of the strike direction which is the azimuth of a horizontal line drawn on the plane of the boundary of discontinuity with which the cursor 25 has been aligned. Both the third and fourth reference pointers utilise the first scale 31 for providing an indication of their relevant measures.

The circular plate of the mounting 23 or the cursor 25 is provided with a circular scale which provides for an indication of the angular orientation of the cursor in order to provide an indication of the dip angle of the feature in the core sample with which the cursor has been aligned.

The embodiment provides a means whereby the position of a core sample within a bore hole can be replicated in order that the relative position of geological features which are observed in the core sample can be accurately determined.

10 It should be appreciated that the scope of the present invention need not be .i limited to the particular scope of the embodiment described above.

o .l

Claims

2. A drill core measuring means as claimed at claim 1 wherein the position of the cursor is displaceable on the second support in a direction substantially 15 parallel to the first axis. S.
3. A drill core measuring means as claimed at claim 1 or claim 2 wherein a first scale is provided between the base and the first support to provide a *measure of relative angular displacement therebetween about the first axis.
4. A drill core measuring means as claimed at claim 1 or claim 2 or claim 3 wherein a second scale is provided between the cradle and the first support to provide a measure of the relative angular displacement therebetween about the second axis. A drill core measuring means as claimed at any one of the preceding claims wherein a third scale is provided between the second support and base to provide a measure of the relative angular displacement therebetween about the first axis. 9
6. A drill core measuring means as claimed at any one of the preceding claims wherein a fourth scale is provided between the cursor and the second support to provide a measure of the angular displacement therebetween about the third axis.
7. A drill core measuring means as claimed at any one of the preceding claims wherein the first and third scales incorporate the points of the Compass.
8. A drill core measuring means as claimed at claim 5 and any one of claims 6 and 7 as dependant from claim 5 wherein the first and third scale comprise the same scale. 10 9. A drill core measuring means substantially as herein described so S Dated this NINETEENTH day of DECEMBER 1997. Stewart Stretch Applicant g. S Wray Associates S. Perth, Western Australia Patent Attorneys for the Applicant s SS