METHOD AND DEVICE FOR DETECTING AND/OR MEASURING AT LEAST ONE GEOPHYSICAL PARAMETER ON A CORE SAMPLE

PROCEDE ET DISPOSITIF DE DETECTION ET/OU DE MESURE D'AU MOINS UN PARAMETRE GEOPHYSIQUE SUR UNE CAROTTE

English Abstract

Method and device for detecting and/or measuring
at least one geophysical parameter from a core sample
(1), in particular in the oil sector, comprising, during
an operation of core drilling with a sampler (2);
arranging, substantially fixed relative to the sampler
(2), a sensor (3) for detecting and/or measuring said
parameter, directly downstream of the exit orifice (5) of
the sampler (2) relative to the direction of withdrawal
of the core sample (1), in the vicinity of the withdrawal
path of the core sample (1), detecting and/or measuring
values, of the parameter at at least one location on the
core sample (1) while the latter is being withdrawn from
and/or moved back in the sampler (2), and processing of
the detected and/or measured values of the parameter, in
order to store them in memory and/or use them
immediately.

French Abstract

Procédé et dispositif de détection et/ou mesure d'au moins un paramètre géophysique sur une carotte (1), en particulier dans le domaine pétrolier, comprenant, lors d'une opération de carottage avec un carottier (2), un agencement, sensiblement fixe par rapport au carottier (2), d'un capteur (3) de détection et/ou mesure dudit paramètre, directement en aval de l'orifice de sortie (5) du carottier (2), par rapport au sens de retrait de la carotte (1), au voisinage du parcours de retrait de la carotte (1), une détection et/ou mesure de valeurs du paramètre en au moins un endroit de la carotte (1) pendant que celle-ci est retirée du et/ou renvoyée dans le carottier (2), et un traitement de valeurs détectées et/ou mesurées du paramètre, pour leur mise en mémoire et/ou utilisation immédiate.

Claims

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WE CLAIM:
1. A method for detecting and measuring at least one
geophysical parameter from a core sample (1), in particular in
the oil sector, characterized in that it comprises, during an
operation of core drilling with a sampler (2);
- arranging, substantially fixed relative to the sampler (2),
a sensor (3) for detecting and measuring said parameter,
directly downstream of an exit orifice (5) of the sampler
(2) relative to the direction of withdrawal of the core
sample (1), in the vicinity of the withdrawal path of the
core sample (1);
- detecting and measuring values of the parameter at at least
one location on the core sample (1) while the latter is
being moved relative to the sampler (2); and
- processing the detected and measured values of the
parameter.
2. The method according to claim 1, characterized in that it
further comprises, simultaneously with the detection and
measurement of the parameter, acquisition of the position of the
location corresponding to this detection and measurement on the
core sample (1) and processing of this acquisition.
3. The method according to claims 1 or 2, characterized in that
it comprises selection of a constant spacing of the successive
detection and measurement locations and a substantially constant
speed of movement of the core sample (1) moved relative to the
sampler (2) during the detection and measurement.
4. The method according to claims 1, 2 or 3, characterized in
that it further includes remote transmission of one or more of
the detected and measured values.

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5. The method according to claim 4, further including the step
of remote transmission of the position of said at least one
location.
6. The method according to claim 3, characterized in that it
further includes remote transmission of one or more of the
detected and measured values.
7. The method according to claim 1, characterized in that it
further includes remote transmission of one or more of the
detected and measured values.
8. The method according to claims 1 or 2, wherein the detected
and measured values of the parameter are processed in order to
store said detected and measured values in electronic memory.
9. The method according to claims 1, 2, or 8, wherein the
detected and measured values of the parameter are processed in
order to use said detected and measured values substantially
immediately.
10. The method according to claims 1 or 2, characterized in that
it comprises selection of a constant spacing of the successive
detection and measurement locations or a substantially constant
speed of movement of the core sample (1) moved relative to the
sampler (2) during the detection and measurement.
11. A method for detecting or measuring at least one geophysical
parameter from a core sample (1), in particular in the oil
sector, characterized in that it comprises, during an operation
of core drilling with a sampler (2);
- arranging, substantially fixed relative to the sampler (2),
a sensor (3) for detecting or measuring said parameter,
directly downstream of an exit orifice (5) of the sampler
(2) relative to the direction of withdrawal of the core

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sample (1), in the vicinity of the withdrawal path of the
core sample (1);
- detecting or measuring values of the parameter at at least
one location on the core sample (1) while the latter is
being moved relative to the sampler (2); and
- processing the detected or measured values of the
parameter.
12. The method according to claim 11, characterized in that it
further comprises, simultaneously with the detection or
measurement of the parameter, acquisition of the position of the
location corresponding to this detection or measurement on the
core sample (1) and processing of this acquisition.
13. The method according to claims 11 or 12, characterized in
that it comprises selection of a constant spacing of the
successive detection or measurement locations and a substantially
constant speed of movement of the core sample (1) moved relative
to the sampler (2) during the detection or measurement.
14. The method according to claims 11, 12 or 13, characterized
in that it further includes remote transmission of one or more
of the detected or measured values.
15. The method according to claim 14, further including the step
of remote transmission of the position of said at least one
location.
16. The method according to claim 13, characterized in that it
further includes remote transmission of one or more of the
detected or measured values.
17. The method according to claim 11, characterized in that it
further includes remote transmission of one or more of the
detected or measured values.

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18. The method according to claims 11 or 12, wherein the
detected or measured values of the parameter are processed in
order to store said detected or measured values in electronic
memory.
19. The method according to claims 11, 12, or 18, wherein the
detected or measured values of the parameter are processed in
order to use said detected or measured values substantially
immediately.
20. The method according to claims 11 or 12, characterized in
that it comprises selection of a constant spacing of the
successive detection or measurement locations on a substantially
constant speed of movement of the core sample (1) moved relative
to the sampler (2) during the detection or measurement.
21. A device for detecting and measuring at least one
geophysical parameter from a core sample (1), in particular in
the oil sector, characterized in that it includes:
- a hollow body (10) having two openings (11, 12) situated
opposite one another along a longitudinal axis (13) of the
hollow body (10), and a free passage (14) extending between
the two openings (11, 12), the two openings (11, 12) and
the free passage (14) being arranged so that a core sample
(1), enclosed in an inner tube (15) of a sampler (2), can
pass freely from one opening to the other (11, 12) through
the hollow body (10);
- fixing means (16) for releasably fixing, optionally with
defined play, the hollow body (10) to an outer tube (17) of
the sampler (2), at the end (22) of the latter through
which a core sample (1) enclosed in an inner tube (15) is
extracted, so that the hollow body (10) is, at least for
the most part, situated in the extension of the outer tube
(17), the longitudinal axes (13 and 18, respectively) of

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the hollow body (10) and of the sampler (2) being
substantially coaxial; and
- at least one sensor (3, 53) for detecting and measuring a
geophysical parameter to be evaluated from a core sample
(1) to be withdrawn from the sampler (2), this detection
and measuring sensor (3, 53) being fixed to the hollow body
(10) in such a way that it is arranged facing the core
sample (1) enclosed in said inner tube (15) when this core
sample is in the aforementioned free passage (14).
22. The device according to claim 21, characterized in that the
fixing means (16) form a detachable constituent assembly of the
hollow body (10) and comprise:
- at least two clamp parts (20, 21) matched to the external
diameter of said outer tube (17) in order to be able to
grip the latter securely in the vicinity of its end (22)
for taking the core sample (1) out;
- linkage (23) and tightening (24) means arranged between the
two clamp parts (20, 21) so that the latter can occupy
relative to one another two separate positions, namely a
first position in which they securely grip said outer tube
(17) when the device (7) is mounted on the latter, and a
second position in which they are separated from one
another for mounting or dismounting the device (7) on or
from the outer tube (17); and
- detachable connection means (30) preferably comprising
projecting elements (31) and recesses (32) arranged on the
hollow body (10) and on the clamp parts (20, 21) in order
to form an interlock linkage which, on the one hand, fixes,
optionally with defined play, the hollow body (10) on the
outer tube (17) when the clamp parts (20, 21) securely grip
the latter when the hollow body (10) is mounted on the
outer tube (17) and which, on the other hand, is released
when the clamp parts (20, 21) are in their second position,

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separated from one another for mounting or dismounting the
hollow body (10) on or from the sampler (2).
23. The device according to claims 21 or 22, characterized in
that the hollow body (10) has an overall U-shape in transverse
section, one longitudinal side (35) of the hollow body (10) being
open over its entire dimension parallel to the axis (13) over a
dimension transverse to this axis (13) at least equal to the
external diameter of the core sample (1) or of the aforementioned
inner tube (15), so as to make it possible to pass the core
sample (1) or, respectively, the inner tube (15), transversely
to the longitudinal axis (13) from the aforementioned free
passage (14), through the open longitudinal side (35), out of the
hollow body (10).
24. The device according to claim 23, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected and measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection and measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
25. The device according to claim 23, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
26. The device according to claim 22, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface

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of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.
27. The device according to claim 26, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected and measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection and measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to it user.
28. The device according to claim 26, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
29. The device according to claim 22, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected and measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection and measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
30. The device according to claim 22, characterized in that it
further includes a radioactive source (6), designed to radiate

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toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
31. The device according to claim 2l, characterized in that the
hollow body (10) has an overall U-shape in transverse section,
one longitudinal side (35) of the hollow body (10) being open
over its entire dimension parallel to the axis (13) over a
dimension transverse to this axis (13) at least
equal to the external diameter of the core sample (1) or of the
aforementioned inner tube (15), so as to make it possible to pass
the core sample (1) or, respectively, the inner tube (15),
transversely to the longitudinal axis (13) from the
aforementioned free passage (14), through the open longitudinal
side (35), out of the hollow body (10).
32. The device according to claim 31, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.
33. The device according to claim 32, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
34. The device according to claim 31, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the

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signals detected and measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection and measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
35. The device according to claim 31, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
36. The device according to claim 21, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.
37. The device according to claim 21, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being on either side of the plane.

-22-
38. The device according to claims 36 or 37, characterized in
that the sensor (3, 53) is connected to a unit (51) for
processing the signals detected and measured by the sensor (3)
and in that the processing unit (51) is connected to a radio
transmitter (52) which is designed for remote transmission of
said processed signals and which is mounted in said detection and
measurement device (7), said radio transmitter (52) being tuned
on a radio receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
39. The device according to claims 36 or 37, characterized in
that it further includes a radioactive source (6), designed to
radiate toward a core sample (1), and a second sensor (53)
designed to measure the absorption of the radiation from the
radioactive source (6) by the core sample (1).
40. The device according to claim 21, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are designed to bear
on the outer surface of the latter which is arranged in the free
passage (14) of the hollow body (10), and in that:
- the hollow body includes an open longitudinal side (35);
- a guide means comprises at least one roller (37B) which can
rotate about an axis of rotation transverse to the
longitudinal axis (13) and which is mounted removably on
the hollow body (10), on the open longitudinal side (35) of
the latter, in order to bear on the inner tube (15) on the
same side (35) of the hollow body (10) relative to the
longitudinal axis (13) and which is mounted fixed on the
hollow body (10);
- at least two other guide means, each comprising at least
one roller (37A) which can rotate about an axis of rotation
transverse to the longitudinal axis (13) and which is
mounted fixed on the hollow body (10); and

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- the axes of rotation of the three rollers (37) being
arranged around the free passage (14) so that the bearing
points of the three rollers (37), projected onto a plane
perpendicular to the longitudinal axis (13), are
substantially regularly distributed about the latter.
41. The device according to claim 21, characterized in that said
at least one sensor (3, 53) includes a crystal connected to a
photo-multiplier (50) in order to detect gamma rays in a core
sample (1).
42. The device according to claim 21, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected and measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection and measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
43. The device according to claim 21, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
44. A device for detecting or measuring at least one geophysical
parameter from a core sample (1), in particular in the oil
sector, characterized in that it includes:
- a hollow body (10) having two openings (11, 12) situated
opposite one another along a longitudinal axis (13) of the
hollow body (10), and a free passage (14) extending between
the two openings (11, 12), the two openings (11, 12) and
the free passage (14) being arranged so that a core sample

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(1), enclosed in an inner tube (15) of a sampler (2), can
pass freely from one opening to the other (11, 12) through
the hollow body (10);
- fixing means (16) for releasably fixing, optionally with
defined play, the hollow body (10) to an outer tube (17) of
the sampler (2), at the end (22) of the latter through
which a core sample (1) enclosed in an inner tube (15) is
extracted, so that the hollow body (10) is, at least for
the most part, situated in the extension of the outer tube
(17), the longitudinal axes (13 and 18, respectively) of
the hollow body (10) and of the sampler (2) being
substantially coaxial; and
- at least one sensor (3, 53) for detecting or measuring a
geophysical parameter to be evaluated from a core sample
(1) to be withdrawn from the sampler (2), this detecting or
measuring sensor (3, 53) being fixed to the hollow body
(10) in such a way that it is arranged facing the core
sample (1) enclosed in said inner tube (15) when this core
sample is in the aforementioned free passage (14).
45. The device according to claim 44, characterized in that the
fixing means (16) form a detachable constituent assembly of the
hollow body (10) and comprise:
- at least two clamp parts (20, 21) matched to the external
diameter of said outer tube (17) in order to be able to
grip the latter securely in the vicinity of its end (22)
for taking the core sample (1) out;
- linkage (23) and tightening (24) means arranged between the
two clamp parts (20, 21) so that the latter can occupy
relative to one another two separate positions, namely a
first position in which they securely grip said outer tube
(17) when the device (7) is mounted on the latter, and a
second position in which they are separated from one
another for mounting or dismounting the device (7) on or
from the outer tube (17); and

-25-
- detachable connection means (30) preferably comprising
projecting elements (31) and recesses (32) arranged on the
hollow body (10) and on the clamp parts (20, 21) in order
to form an interlock linkage which, on the one hand, fixes,
optionally with defined play, the hollow body (10) on the
outer tube (17) when the clamp parts (20, 21) securely grip
the latter when the hollow body (10) is mounted on the
outer tube (17) and which, on the other hand, is released
when the clamp parts (20, 21) are in their second position,
separated from one another for mounting or dismounting the
hollow body (10) on or from the sampler (2).
46. The device according to claims 44 or 45, characterized in
that the hollow body (10) has an overall U-shape in transverse
section, one longitudinal side (35) of the hollow body (10) being
open over its entire dimension parallel to the axis (13) over a
dimension transverse to this axis (13) at least equal to the
external diameter of the core sample (1) or of the aforementioned
inner tube (15), so as to make it possible to pass the core
sample (1) or, respectively, the inner tube (15), transversely
to the longitudinal axis (13) from the aforementioned free
passage (14), through the open longitudinal side (35), out of the
hollow body (10).
47. The device according to claim 46, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected or measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection or measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.

-26-
48. The device according to claim 46, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
49. The device according to claim 45, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.
50. The device according to claim 49, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected or measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection or measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to it user.
51. The device according to claim 49, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
52. The device according to claim 45, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the

-27-
signals detected or measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection or measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
53. The device according to claim 45, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
54. The device according to claim 44, characterized in that the
hollow body (10) has an overall U-shape in transverse section,
one longitudinal side (35) of the hollow body (10) being open
over its entire dimension parallel to the axis (13) over a
dimension transverse to this axis (13) at least equal to the
external diameter of the core sample (1) or of the aforementioned
inner tube (15), so as to make it possible to pass the core
sample (1) or, respectively, the inner tube (15), transversely
to the longitudinal axis (13) from the aforementioned free
passage (14), through the open longitudinal side (35), out of the
hollow body (10).
55. The device according to claim 54, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),

-28-
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.
56. The device according to claim 55, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
57. The device according to claim 54, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected or measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection or measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
58. The device according to claim 54, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
59. The device according to claim 44, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being substantially in the same plane.

-29-
60. The device according to claim 44, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are fixed to the
hollow body (10) and designed so as to bear on the outer surface
of the abovementioned inner tube (15) arranged in the hollow body
(10), the bearing taking place at at least three contact points
which, seen in projection onto a plane perpendicular to the
abovementioned substantially coaxial longitudinal axes (13, 18),
are distributed over 360 degrees around the inner tube (15),
these bearing points being on either side of the plane.
61. The device according to claims 59 or 60, characterized in
that the sensor (3, 53) is connected to a unit (51) for
processing the signals detected or measured by the sensor (3) and
in that the processing unit (51) is connected to a radio
transmitter (52) which is designed for remote transmission of
said processed signals and which is mounted in said detection or
measurement device (7), said radio transmitter (52) being tuned
on a radio receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
62. The device according to claims 59 or 60, characterized in
that it further includes a radioactive source (6), designed to
radiate toward a core sample (1), and a second sensor (53)
designed to measure the absorption of the radiation from the
radioactive source (6) by the core sample (1).
63. The device according to claim 44, characterized in that it
further includes means (36) for guiding the hollow body (10)
relative to the inner tube (15), which means are designed to bear
on the outer surface of the latter which is arranged in the free
passage (14) of the hollow body (10), and in that:
- the hollow body includes an open longitudinal side (35);
- a guide means comprises at least one roller (37B) which can
rotate about an axis of rotation transverse to the

-30-
longitudinal axis (13) and which is mounted removably on
the hollow body (10), on the open longitudinal side (35) of
the latter, in order to bear on the inner tube (15) on the
same side (35) of the hollow body (10) relative to the
longitudinal axis (13) and which is mounted fixed on the
hollow body (10);
- at least two other guide means, each comprising at least
one roller (37A) which can rotate about an axis of rotation
transverse to the longitudinal axis (13) and which is
mounted fixed on the hollow body (10); and
- the axes of rotation of the three rollers (37) being
arranged around the free passage (14) so that the bearing
points of the three rollers (37), projected onto a plane
perpendicular to the longitudinal axis (13), are
substantially regularly distributed about the latter.
64. The device according to claim 44, characterized in that said
at least one sensor (3, 53) includes a crystal connected to a
photo-multiplier (50) in order to detect gamma rays in a core
sample (1).
65. The device according to claim 44, characterized in that the
sensor (3, 53) is connected to a unit (51) for processing the
signals detected or measured by the sensor (3) and in that the
processing unit (51) is connected to a radio transmitter (52)
which is designed for remote transmission of said processed
signals and which is mounted in said detection or measurement
device (7), said radio transmitter (52) being tuned on a radio
receiver located remotely and designed to receive said
transmitted signals and to send them to a user.
66. The device according to claim 44, characterized in that it
further includes a radioactive source (6), designed to radiate
toward a core sample (1), and a second sensor (53) designed to

-31-
measure the absorption of the radiation from the radioactive
source (6) by the core sample (1).
67. A device for detecting and measuring at least one parameter
of a core sample, comprising:
- a longitudinally extending hollow body having a
longitudinally extending free passage;
- a fixing assembly for releasably fixing said hollow body to
an outer tube of a longitudinally extending sampler, at the
end of said sampler, through which a core sample enclosed
in an inner tube is extracted, whereby said hollow tube is
situated as an extension of said outer tube and the
longitudinal axes of said hollow body and said sample are
coaxial; and
- at least one sensor fixed to said hollow body with said
sensor facing said core sample when said core sample is in
said free passage of said hollow body.
68. A device for detecting or measuring at least one parameter
of a core sample, comprising:
- a longitudinally extending hollow body having a
longitudinally extending free passage;
- a fixing assembly for releasably fixing said hollow body to
an outer tube of a longitudinally extending sampler, at the
end of said sampler, through which a core sample enclosed
in an inner tube is extracted, whereby said hollow tube is
situated as an extension of said outer tube and the
longitudinal axes of said hollow body and said sample are
coaxial; and
- at least one sensor fixed to said hollow body with said
sensor facing said core sample when said core sample is in
said free passage of said hollow body.

Description

21678.25
"Method and device for detecting and/or measurinct at
least one geophysical parameter from a core sample"
The present invention relates to a method for
detecting and/or measuring at least one geophysical
parameter from a core sample, in particular in the oil
sector.
Geophysical parameters which are of interest to
the person skilled in the art in the study of oil wells
being drilled are, for example, the natural radioactivity
of the core sample, the absorption of a known radiation
emitted by a known source arranged in proximity to the
core sample, and the value of the liquid saturation of
the core sample (Which value is measured by induction).
To date, this type of parameter has been measured
and/or detected by arranging the core sample which has
been withdrawn from the well substantially horizontally
on the ground and by moving a carriage equipped with the
measuring instrument or instruments manually along the
core sample.
This procedure has significant disadvantages,
including the fact that it a.s first necessary to handle
the core sample. Although it is contained in an inner
tube of the sampler, it is necessary, in order to
transport the core sample, for example in order to lay it
on the ground, to detach the successive inner tubes from
one another, break the core sample at the junctions of
these tubes and to cut the core sample, together with the
inner tube containing it, into transportable sections of
the order of approximately one meter in length, and it is
necessary to close the ends of these sections. This
sectioning and the operations of closure and transport
affect the strata in the core sample, especially at the
two ends of each section, and therefore distort the
information which could be extracted from the
measurements taken along the sections and mainly at their
ends.
Since the carriage is moved by hand, the speed
imparted to it is not uniform, and this may compromise
accuracy of the measurements.

267825
- 2 -
Parameters of the abovementioned type can be
influenced by the environment of the core sample at the
time of measurement, or else similar parameters origina-
ting from the environment may be added to the correspon-
ding parameters of the core sample during the measurement
taken therefrom. Thus, when the core sample is arranged
horizontally, since one of its sides is closer to the
ground than the other, this difference in distance may
affect the result of the measurement, or else the ground
may influence the instruments because of its proximity,
this being increasingly so since this proximity is
asymmetrical relative to the mass of the core sample as
a whole. Overall, lack of accessibility to the core
sample makes it impossible to optimize the measurement.
The object of the present invention is to over-
come these problems by making it possible to detect
and/or measure geodesic parameters from a core sample
which has been handled as little as possible, for example
because it has not yet been cut into sections, and Which
is situated in such a way that it is influenced by the
environment as little as possible or as symmetrically as
possible, because it is, for example, still held, until
the time of detection and/or measurement, in the vertical
position (therefore under symmetrical influence from the
ground) and shielded in the outer tube of the sampler,
which is made of metal and therefore forms a screen
against certain influences of the surrounding ground.
In order to solve the abovementioned problems
according to the invention, the process comprises, during
an operation of core drilling with a sampler;
- arranging, substantially fixed relative to the
sampler, a sensor for detecting and/or measuring
said parameter, directly downstream of the exit
orifice of the sampler relative to the direction of
withdrawal of the core sample, in the vicinity of
the withdrawal path of the core sample,
- detecting and/or measuring values of the parameter
at at least one location on the core sample while
the latter is being withdrawn from and/or moved back

216725
- 3 -
in the sampler, and
- processing of the detected and/or measured values of
the parameter, in order to store them in memory
and/or use them immediately.
The present invention also relates to a device
for detecting and/or measuring at least one geophysical
parameter from a core sample, in particular in the oil
sector.
According to the invention, the said device
includes:-
- a hollow body having two openings situated opposite
one another along a longitudinal axis of the hollow
body, and a free passage extending between the two
openings , the latter and the free passage being
arranged so that a core sample, enclosed in an inner
tube of the sampler, can pass freely from one
opening to the other through the hollow body,
- fixing means for releasably fixing, optionally with
defined play, the hollow body to an outer tube of
the sampler, at the end of the latter through which
a core sample enclosed in an inner tube is extrac-
ted, so that the hollow body is, at least for the
most part, situated in the extension of the outer
tube, the longitudinal axes of the hollow body and
of the sampler being substantially coaxial, and
- at least one sensor for detecting and/or measuring
a geophysical parameter to be evaluated from a core
sample to be withdrawn from the sampler, this detec-
tion and/or measuring sensor being fixed to the
hollow body in such a way that it is arranged facing
the core sample enclosed in said inner tube when
this core sample is in the aforementioned free
passage.
Other details and particular features of the
invention will emerge from the secondary claims and from
the description of the drawings which are appended to the
present document and which illustrate, by way of non-
limiting examples, the method and one particular embodi-
ment of the device according to the invention.

267825
- 4 -
Figure 1 shows a view in elevation and with
partial cutaway of a device of the invention for imple-
menting the method of the invention, the device being
installed on a sampler and being used.
Figure 2 is a view with cross section, on the
line II-II of Figure 1 and along the associated arrows,
showing the fixing of the aforementioned device to the
sampler.
Figure 3 is a view with cross section, on the
line III-III of Figure 1 and along the associated arrows,
showing guiding of the aforementioned device relative to
a sampler inner tube passed into the device.
In the various figures, the same reference .
numerals denote identical or similar elements.
The method according to the invention a.s intended
for detecting and/or measuring at least one geophysical
parameter from a core sample 1 (Figure 1), for example in
oil industry core drilling. A geophysical parameter of
this type may be natural radioactivity of the
constituents of the core sample, absorption of the
radiation emitted by a known radiation source, etc.
According to the invention, the method comprises,
during an operation of core drilling with a sampler 2,
arranging, substantially fixed relative to the sampler 2,
a sensor 3 for detecting and/or measuring the parameter
in question, directly downstream, at 4, of the exit
orifice 5 of the sampler 2 relative to the direction of
withdrawal of the core sample 1 in the immediate vicinity
(known to the person skilled in the art) of the with-
drawal path of the core sample 1. For example, the sensor
3 may be an NaI crystal which detects the radiation
fraction, from a known cesium-137 source of 1 millicurie
and situated at 6, which is not absorbed by the con-
stituents of the core sample 1, in order to determine
therefrom the radiation fraction absorbed by these
constituents. The value of the parameter is therefore
detected and/or measured by this sensor 3 at one or more
locations on the core sample 1 while the latter is
withdrawn from the sampler 2 by known means and/or is

~16~8~~
-5_
moved back therein by these means. This procedure may
have the purpose, for example, of performing the same
detection and/or measurement several times at a plurality
of locations over the length of the core sample 1 which
has just been taken and which is still only at the first
handling stages, in contrast to the prior method, without
therefore being cut and moved from a practically vertical
position to, for example, a horizontal position before
the abovementioned detection and/or measurement takes
place. Preliminary processing of the values delivered by
the detection and/or measurement may then also take place
directly at the core drilling site, for example for the
purpose of sorting these values in order to store them in-
memory or to use them immediately, as explained below.
Preferably, the method according to the invention
further includes, simultaneously with the aforementioned
detection and/or measurement at 3, acquisition of the
position of the location corresponding to this detection
and/or measurement on the core sample 1 and, after this
acquisition, processing thereof in order to store a.t in
memory and/or use it immediately, for example in order to
determine the segments of the core sample 1 which exhibit
particular detection and/or measurement results.
Advantageously, a substantially constant separa
tion between two detection locations can be selected so
as, for example, to facilitate this assignment of each
detection and/or measurement location to this detection
and/or measurement, or to make it possible to observe a
change in the latter more easily. In addition, selection
of a substantially constant speed of displacement during
withdrawal of the core sample 1 from the sampler 2 or
movement thereof back in the latter may be beneficial for
detections and/or measurements which are influenced by
this speed of displacement. Until now, this has resulted
from a manual action during displacement of the
aforementioned carriage and it is therefore essentially
nonuniform.
Since detections and/or measurements are carried
out, according to the invention, directly at the drilling

CA 02167825 2000-06-28
- 6 -
site, it is preferable, for example in order to analyze
them immediately, to transmit them remotely from the
abovementioned site to where an operator can process them
under shelter and out of the way of the workers
undertaking the drilling or core sampling proper.
The invention also relates to the device men-
tioned above. In i.t;s simple form, this device 7 includes
a hollow body 10 having two openings 11 and 12 situated
opposite one another along a longitudinal axis 13 of the
hollow body 10. A free passage 14 extends between the
openings 11 and 12 and is arranged relative thereto so
that a core sample 7., enclosed in an inner tube 15 of the
sampler 2, can pass; freely through the hollow body 10.
The device 7 further includes fixing means 16 for
releasably fi:cing the hollow body 10 to an outer tube 17
of the sampler 2, .at the end 22 of the latter through
which a core samples 1 enclosed in the inner tube 15 is
extracted from the aampler 2. The hollow body 10 is then
fixed therein so as to be situated, at least for the most
part, in the extension of the outer tube 17, the
longitudinal .axes 13, of the hollow body 10, and 18 of
the sampler 2, being substantially coaxial. The hollow
body 10 includes at least one sensor 3 for detecting
and/or measuring a geophysical parameter to be evaluated
from the core sample 1 to be withdrawn from the sampler
2. The sensor 3, an. example of which is given above, is
fixed to the hollow body 10 in order to be arranged
facing the core sample 1 when the latter is in the free
passage 14.
Prefe:cably, the aforementioned fixing means
16 may constitute a.n assembly that can be detached from
the hollow body 10 and may comprise (Figure 3 ) two
clamping parts 20 and 2:1 matched to the external diameter
of the outer tubEa 17 in order to be able to grip this
tube 1'7 forcibly in the vicinity of its end 22 for
extraction of the core sample 1. Linkage 23 and
tightening means :?.4 are arranged between the two clamping
parts 2,0 and 21. The linkage means 23 are formed, for
example, by a l.i:nkage cross member 23 which joins

CA 02167825 2000-06-28
_ 7 _
together, in articulated fashion, one end of a clamping
part 20 to a corresponding end of the other clamping part
21, so that these clamping parts 20, 21 can be moved
freely, in or~3er to grip and to release the end 22, in a
plane substantial.l~~ perpendicular to the longitudinal
axis 18. The two clamping parts 20 and 21 can then be
arranged to occupy two separate positions relative to one
another, namely a first position in which (Figures 1 and
3) they securely grip the outer tube 17 when the device
7 is mounted thereon, and a second position (not repre-
sented) in which the c:Laimping parts 20 and 21 are sepa-
rated from one another by a distance greater than the
external diameter of the outer tube 17, so ae to make it
possible to mount t:he fixing means 16 and therefore the
device 7 on the outer tube 17, or to remove them there-
from.
In the example represented in Figure 3 , the
clamping parts 20 and 21 and the crossmember 23 each
include an internal boss 25, an internal peripheral
surface of which is matched to said external diameter of
the outer tutee 17, the three internal bosses 25 being
regularly distributed around the outer tube 17.
For the abovementioned gripping, the aforemen
tioned tightening means 24 are, for example, a screw
26 passing through a smooth hole 27 made in the free end
of the clamping part 21, and in a threaded hole 28 made
in the free e:ad of the clamping part 20. Advantageously,
the screw 26, the smooth hole 27 and the threaded hole
28 have, when the :Linkage 23 and clamping means 24 are
mounted on the outer tube 17, a common axis which is
parallel to the aforementioned plane perpendicular to the
longitudinal axis 7_8, and which extends on the opposite
side of the outer tube 17 relative to the cross member
23, preferably parallel to the latter.
In order to connect the hollow body 10 proper to
the linkage 23 and tightening means 24, connection means
30 are provided which may comprise projecting elements
31 and recesE~es .32 arranged on the hollow body 10 and,
for example, on t:he clamping parts 20 and 21, as repre-

CA 02167825 2000-06-28
- 8 -
sented by Figure 3. In this figure, each projection 31 is
a protruding pin :31 fixed to the clamping part 20 or
21 in such a way that the two pins 31 are coaxial along
a diameter oi: the outer tube 17, when the fixing means
16 grip the latter with the device 7 being mounted, and
in such a way that the free end of each pin 31 is turned
toward the longitudinal axis 18. In the aforementioned
mounted state:, represented in Figures 1 and 3. the pins
31 are passed through recesses or openings 32 made in
corresponding lugs 33 of the hollow body 10, which are
fixed thereto at that end of it which is to be placed on
the outer tube 17. An interlock linkage is thus produced
between the hollow body 10 and the linkage 23 and .
clamping means 24.
Preferably, play is provided between each pin
31 and the corresponding opening 32, for reasons
explained below.
The aforementioned interlock linkage can be
released, in 'the case of the above example, by unscrewing
the screws 26 so that the clamping parts 20 and 21 can be
moved away from ones another in order to untighten their
grip on the outer tube 17, until the pins 31 can be
withdrawn from the apenings 32.
Advantageously, in order to allow possible
mounting or dismounting of the hollow body 10 on or from
the sampler 2, this body has an overall U-shape in cross
section at it;s axis 13. One longitudinal side 35 (Figures
1 and 3) of the hollow body 10 is actually open over its
entire dimension, taken parallel to the longitudinal axis
13, and over its transverse dimension at least equal to
the external diameter of the core sample 1 or, prefer-
ably, of the inner tube 15. The device 7 can thus be
fitted on thE: core sampler 2 or withdrawn therefrom by
displacement transverse to the axis 13 or 18 so that the
core sample .L or the :inner tube 15 can thus, partially
extracted from t:h~= sampler 2, easily enter the free
passage 14 from the outside' of the hollow body 10, or
vice versa, when t:he latter is mounted on the sampler 2
or, respectively, during dismounting.

CA 02167825 2000-06-28
_ g _
In a prefearred embodiment of the invention,
represented in Figures 1 and 3, the device 7 further
includes meana 36 for guiding the hollow body 10 relative
to the inner tube 15. These guide means 36, comprising
rollers 37 whose axis of rotation is in each case in a
plane perpenclicular to the longitudinal axis 13, are
arranged so a.s to bear on the external surface of the
aforementioned inner tube 15 when the latter is arranged
in the hollow body 10, in the measurement and/or detec-
tion position. For example, the axes of rotation of the
two rollers 3'7A may be fixed relative to the hollow body
10 and may be situated in the same plane perpendicular to
the longitudinal aacis 13, preferably opposite the open
longitudinal side 35 relative to the longitudinal axis
13. In the present exemplary embodiment, two other
rollers 37B m.ay be provided on a support 38 mounted on
the hollow body 10 by means, on the one hand, of a hinge
39 and, on t.h.e othcar hand, of a screw 40 and of a com-
pression spring 41,, so as to be capable of closing or
opening tie longit:udinal side 35 by means of this support
38 and the rollers 37B. The axes of rotation of the two
rollers 37B are in planes perpendicular to the longitudi-
nal axis 13 and situated on either side of the common
perpendicular plane: of the axes of the rollers 37A. The
projections of the rol:Lers 37A and 37B onto this latter
plane are distributed over 360° around the projection of
the inner tube 15 onto this same plane.
As shown by Figure 1, the guide rollers 37 are
situated at the end of the hollow body 10 away from the
sampler 2 when the device 7 is mounted on the sampler 2.
In one embodiment of the invention, the sensor 3 ,
formed by an Na:L crystal, is connected to a photo
multiplier 50 in order to detect gamma rays emitted by
the core sample 1 or to measure these rays absorbed by
this core sample 1..
In order to analyze the detection and/or measure-
ment, the sensor 3 may be connected by the photomulti-
plier 50 to a unit: 51 for processing the signals from the
sensor 3, and this processing unit 51 may be connected to

- ~ 216725
-lo-
a transmitter 52, for example a VFiF radiotransmitter,
which is designed to transmit the processed signals over
a distance of 50 to 100 m and which is incorporated in
the device 7. The transmitter 52 is then, via its antenna
52A, tuned to a radio receiver (not represented) designed
to receive the transmitted processed signals and to send
them to a user. Preferably, the aforementioned transmit-
ter 52 and receiver are each a combined transmitter/
receiver and are designed so that they can, in addition,
control the processing unit 51 from the receiver (not
represented), via the transmitter 52.
A radioactive source 6 may be arranged in the
hollow body 10 in order to radiate toward the core sample
1. The aforementioned sensor may then be designed to
measure the absorption of the radiation from the source
6 by the core sample 1. A second sensor 53 may be mounted
in the hollow body 10 in order to measure natural radia-
tion originating from the core sample 1. This sensor 53
is then also connected to the processing unit 51 which,
in this case, is designed to process the signals from the
second sensor 53 as well and to transmit them, as above,
with a view to using them away from the drilling platform
which is the site of core drilling and use of the device
7.
The device 7 preferably includes its own
batteries 55 for powering the aforementioned measurement,
detection, processing, transmission, etc. means.
In order to use the device 7, the inner tube 17
of the sampler 2 may, for example, be blocked in the
revolving table 60 (Figure 1) of the drilling platform,
by wedging blocks 61. The upper end 62 of the inner tube
15 may be grasped by known means 63, for the purpose of
withdrawing this inner tube 15 and the core sample 1 from
the drilled well. These grasping means 63 are, for
example, suspended by a cable from a winch (which are not
represented).
The hollow body 10 may be introduced transversely
to the axis 18, when the support 38 is pivoted so as to
free the open longitudinal side 35, and the hollow body

. 2167825
- 11 -
is placed on the upper end 22 of the outer tube 17 in
order to be fixed thereto by the fixing means 16. A
damping washer 64 (Figure 1) may be arranged between the
hollow body 10 and the aforementioned upper end 22. After
5 this fixing has been carried out by inserting the pins 31
into the corresponding holes 32 and by tightening the
screw 26, the support 38 is positioned so as to close the
longitudinal side 35 and the screw 40 is tightened in
order, by means of the spring 41, to press the rollers
10 37B in contact with the external surface of the inner
tube 15 which also comes into contact with the rollers
37A.
Once the device 7 has thus been installed, the
detection and/or measurement, signal processing and
transmission equipment can then be engaged in order to
measure and/or detect parameters, process them,
optionally store them in a memory incorporated in the
device 7 and/or transmit them remotely. The aforemen-
tioned winch is turned on in order to withdraw the inner
tube 15 and the core sample 1 which it carries. The
measurements and/or detections are carried out. If
necessary, the inner tube 15 and the core sample 1 are
lowered in the outer tube 17 in order to be pulled out of
it again, so as to repeat the measurements and/or
detections either during descent or during descent and
raising, and this can be repeated as often as desired, at
a desired speed that is preferably constant.
After measurement and/or detection from the core
sample 1, the device 7 can be withdrawn by reversing the
sequence of operations mentioned above and the core
sample 1 can then be processed in a conventional manner,
for other analyses that are useful in the case of the
abovedescribed type of drilling.
It should be understood that the invention is in
no way limited to the described embodiments, and that
many changes may be made to these embodiments without
departing from the scope of the present invention.
For example, an encoding wheel system for the
displacement and/or distance travelled by the inner tube

2167~~5
- 12 -
15 may be used for correlating a measurement location and
the corresponding measurement, it being possible for this
system to be connected to the winch or to be directly in
contact with the inner tube 15.
A screen may be provided in order to close the
longitudinal side 35, and thereby to avoid unbalanced
influencing of the core sample l, intended for detection
and/or measurement, by the device 7 and/or the
environment.

Representative Drawing