Note: Descriptions are shown in the official language in which they were submitted.
CA 03011167 2018-07-10
DESCRIPTION
PREDICTION APPARATUS AND METHOD OF PREDICTING DESORBED GAS
VOLUME OF SHALE GAS RESERVOIR USING GEOPHYSICAL LOGGING DATA
ANALYSIS
Technical Field
[0001) The present invention relates to a prediction
apparatus and a method of predicting a desorbed gas volume
of a shale gas reservoir. More particularly, the present
invention relates to a prediction apparatus and a method of
predicting a desorbed gas volume of a shale gas reservoir
using a geophysical logging data analysis which enables the
desorbed gas volume of the shale gas reservoir to be
predicted by: deriving a correlation of a geophysical
logging data analysis result by mineral and a measured
canister gas volume value; selecting major minerals having
correlationship exceeding preset reference values; and using
correlation of derived major mineral contents and the
measured canister gas volume value after deriving the
selected major mineral contents.
Background Art
[0002] A traditional gas is moved and trapped in
reservoir rocks having high porosity and permeability after
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having been generated from organic matter inside a source
rock. For shale gas, remaining gases are trapped by being
adsorbed to organic porosities inside a source rock, after
gases having been formed from organic matter inside the
source rock move to reservoir rocks. Since shale
gas is
trapped in hale having low permeability, the gas is produced
by hydraulic fracturing after horizontal boring along a
shale gas reservoir including a large volume of gas, which
is different from a traditional gas production method.
W Accordingly, selection of a shale gas reservoir having a
large volume of gas is necessary for success of a shale gas
operation.
[0003] In addition,
shale gas is distributed in very
tight shale differently from traditional gas resources, and
shows a feature that characteristics of rock physics and
geochemistry inside a reservoir ,are heterogeneous.
Accordingly, for effective and sustainable production of
shale gas, characteristics analysis of rock physics and
geochemistry inside a reservoir are important. Particularly,
gas produced from a shale gas reservoir is originated from a
free gas being confined in porosities or cracks inside a rock
and a desorbed gas adsorbed on organic matter surfaces.
Meanwhile, an assessment for a case of the free gas may be
performed by a traditional method, whereas a standardized
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assessment technique for a case of the desorbed gas is not
available yet.
Disclosure
Technical Problem
[0004] Accordingly,
the present invention has been made
keeping in mind the above problems occurring in the prior
art, and an object of the present invention is to resolve
conventional problems described as above and to provide a
W prediction apparatus and method of a desorbed gas volume of
a shale gas reservoir using a geophysical logging data
analysis which enables the desorbed gas volume of the shale
gas reservoir to be rapidly and accurately predicted and an
effective and sustainable production of shale gas to be
Is possible: by selecting minerals having a high correlation as
major adsorption minerals as major adsorption factors
through an interaction formula using a correlation of
mineral and organic matter contents analyzed from a boring
core of a reservoir and a canister gas volume; and by
20 allowing the desorbed gas volume distributed inside the
shale gas reservoir to be predicted by using the correlation
after deriving selected major mineral contents.
Technical Solution
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[0005] In order to accomplish the above object, the
present invention provides a prediction apparatus of a
desorbed gas volume of a shale gas reservoir using a
geophysical logging data analysis, and the prediction
apparatus is configured to include:
[0006] a mineral and organic matter content analysis part
analyzing mineral and organic matter contents by thermal
analysis of a shale sample collected from a borehole;
[0007] a canister gas volume measurement part measuring
gas contents by using a gas inside a canister sealing a
collected shale sample;
[0008] a correlation analysis part extracting minerals
having a correlation exceeding a preset reference value as
major adsorption minerals by analyzing a correlation of the
minerals and the gas contents;
[0009] a major adsorption mineral content derivation part
deriving contents of the major adsorption minerals being
extracted; and
[0010] a desorbed gas volume prediction part predicting
contents of a gas adsorbed in a shale gas reservoir by using
an interaction formula of derived contents of the major
adsorption minerals and the correlation.
[0011]
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[0012] The mineral and
organic matter content analysis
part may be configured to analyze TOO of organic matter and
constituent and contents of minerals through XRD analysis.
[0013]
[0014] The mineral and organic
matter content analysis
part may be configured to perform analyses of logging data by
natural gamma radiation, neutron porosity, density,
electrical resistivity, and sonic logging.
[0015]
W [0016] The mineral and
organic matter content analysis
part may be configured to calculate a volume of shale by
using a gamma-ray logging and a combination of neutron
porosity and density logging.
[0017]
[0018] After classifying
collected samples into the major
adsorption minerals and remainders excluding the major
adsorption minerals as a clay mineral, the contents of the
major adsorption minerals are derived by the formula:
VSh = psh¨ Iiish = pclays
Tinain=
pmain¨ pciays , where
Vmain is a volume of
the major adsorption minerals, pmain a density of the major
adsorption minerals, pclays a density of the clay mineral,
Vsh a volume of the shale, and psh a density of the shale.
[0019]
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[0020] In order to accomplish the above object, the
present invention provides a method of predicting a desorbed
gas volume of a shale gas reservoir using a geophysical
logging data analysis, and the method is configured to
include:
[0021] performing a mineral and organic matter content
analysis analyzing mineral and organic matter contents by
thermal analysis on a shale sample collected from a borehole
by the mineral and organic matter content analysis part;
[0022] performing a canister gas volume measurement
measuring gas contents by using a gas inside a canister
sealing a collected sample by the canister gas volume
measurement measuring gas contents part;
[0023] performing a correlation analysis extracting
minerals having a correlation exceeding preset reference
value as major adsorption minerals by analyzing a correlation
of the minerals and the gas contents by the correlation
analysis part;
[0024] performing a major adsorption mineral content
derivation deriving contents of the major adsorption minerals
being extracted by the major adsorption mineral content
derivation part; and
[0025] performing a desorbed gas volume prediction
predicting contents of a gas adsorbed in a shale gas
reservoir by using derived contents of the major adsorption
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minerals and the correlation by the desorbed gas volume
prediction part.
[0026]
[0027] The
performing mineral and organic matter content
analysis may be a process of analyzing TOO of an organic
matter and constituent and contents of minerals through XRD
analysis.
[0028]
[0029] The
performing mineral and organic matter content
analysis may further include a process of performing analyses
of logging data by natural gamma radiation, neutron porosity,
density, electrical resistivity, and sonic logging.
[0030]
[0031] The
performing mineral and organic matter content
analysis may further include a process of calculating a
volume of shale by using gamma-ray logging and a combination
of neutron porosity and density logging.
[0032]
[0033] After
classifying the collected samples into the
major adsorption minerals and remainders excluding the major
adsorption minerals as a clay mineral, the major adsorption
minerals are derived by the following formula:
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= VSh psh¨ Vsh pdays
timain
[0034] pain¨ Mays , where
Vmain is a
volume of the major adsorption minerals, pmain a density of
the major adsorption minerals, pclays a density of the clay
mineral, Vsh a volume of the shale, and psh a density of the
shale.
Advantageous Effects
[0035] As described
above, the present invention
provides an effect which enables the desorbed gas volume of
a shale gas reservoir to be rapidly and accurately predicted
and an effective and sustainable production of shale gas to
be possible: by selecting minerals having high correlation
as major adsorption minerals as major adsorption factors
through an interaction formula using a correlation of
mineral and organic matter contents analyzed from a boring
core of a reservoir and a canister gas volume; and by
allowing the desorbed gas volume distributed inside the
shale gas reservoir to be predicted by using the correlation
after deriving selected major mineral contents.
Description of Drawings
[0036] FIG. 1 is a
block diagram of a prediction
apparatus 1 of a desorbed gas volume of a shale gas
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reservoir using a geophysical logging data analysis
according to an embodiment of the present invention.
[0037] FIG. 2 is a flow chart showing a process of a
prediction method of the desorbed gas volume of a shale gas
reservoir using a geophysical logging data analysis of the
present invention.
[0038] FIG. 3 depicts graphs each showing a correlation
of one of a combination of minerals inside a collected
sample and a canister gas volume.
Mode for Invention
[0039] In describing the present invention, detailed
descriptions of prior arts and constituents which have been
deemed to obfuscate the gist of the present invention will
be omitted below.
[0040]
[0041] Since embodiments according to a concept of the
present invention may be modified in various ways and have
many types, specific embodiments will be illustrated in
drawings and described in detail in the present description
or application. However, it is to be understood that the
embodiments according to the concept of the present
invention are not limited to a specific disclosure, but, on
the contrary, are intended to cover all kinds of
modifications, equivalent arrangements or substitutes
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included within the spirit and technical scope of the
present invention. In addition, a term "exemplary" is used
to mean "as an example", "for example", or "plays a role as
an illustration". Any aspects described with "exemplary" in
this description should not be necessarily interpreted as
they must be preferable to or advantageous than other
aspects.
[0042]
[0043] When a
constituent is referred to as being
W "connected" or "joined" to another constituent, this should
be understood that the constituent may be directly connected
or joined to the other constituent, but a different
constituent may be interposed therebetween. In contrast,
when a constituent is referred to as being "directly
connected" or "directly joined" to another constituent, this
should be understood that no different constituent is
interposed therebetween. Other expressions to explain
relationship between other constituents such as "between"
and "just between" or "adjacent to" and "directly adjacent
to" should be understood in the same way.
[0044] Terms used
in the present specification are used
to describe only specific embodiment and are not intended to
limit the present disclosure. An expression in a singular
form includes an expression in a plural form, unless the
meaning is not obviously different conextually. It should
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be understood that terms such as "include" or "have" in the
present disclosure are intended to designate the existence
of a character, a numeral, a step, a movement, a
constituent, a parts, or a combination of these which are
embodied, and not to exclude at least one of other
character, numeral, step, movement, constituent, parts, or
combination of these, or an additional possibility.
[0045]
[0046] Hereinafter, the present invention will be
described in more detail with reference to the accompanying
drawings illustrating embodiments of the present invention.
[0047] Embodiments of the present invention predicted a
desorbed gas volume inside shale by deriving major
adsorption minerals by analyzing a correlation of mineral
0 and organic matter (TOC) contents analyzed from a boring
core of the Montney Shale Gas Reservoir and a canister gas
volume, and by deriving an interaction formula extracting
contents of major adsorption minerals.
[0048]
[0049] FIG. 1 is a block diagram of a prediction
apparatus 1 of a desorbed gas volume of a shale gas
reservoir using a geophysical logging data analysis
according to an embodiment of the present invention.
[0050] As illustrated in FIG. 1, the prediction
apparatus 1 of the desorbed gas volume of the shale gas
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reservoir is configured to include: a mineral and organic
matter content analysis part 10, a canister gas volume
measurement part 20, a correlation analysis part 30, a major
adsorption mineral content derivation part 40, and a
desorbed gas volume prediction part 50.
[0051] The mineral
and organic matter content analysis
part 10 is configured to analyze mineral and organic matter
contents by thermal analysis on a shale sample collected
from a borehole.
Specifically, the mineral and organic
matter content analysis part 10 is confjgured to analyze TOO
and kinds and contents of minerals through XRD analysis,
natural gamma radiation, neutron porosity, density,
electrical resistivity, and sonic logging. In addition, a
volume of shale is configured to be calculated by using
gamma-ray logging and a combination of neutron porosity and
density logging.
[0052] The canister
gas volume measurement part 20 is
configured to measure gas contents by using a gas inside a
canister sealing a collected shale sample.
[0053] The correlation
analysis part 30 is configured to
perform correlation analysis extracting minerals having high
correlation (exceeding preset reference value) as major
adsorption minerals having large gas adsorption volume by
analyzing correlation of the mineral and gas contents.
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[0054] The major
adsorption mineral content derivation
part 40 is configured to derive contents of the major
adsorption minerals being extracted. In other words, after
classifying the collected samples into major adsorption
minerals and remainders excluding major adsorption minerals
as a clay mineral, the contents of the major adsorption
minerals are derived by the formula:
TT TirS h # psh¨ fish pelays
main ¨
pmcall pc
lays , where
Vmain is a volume of
the major adsorption minerals, pmain a density of the major
adsorption minerals, pclays a density of the clay mineral,
Vsh a volume of the shale, and psh a density of the shale.
[0055] The desorbed
gas volume prediction part 50 is
configured to predict contents of a gas adsorbed in a shale
gas reservoir by inversely applying the interaction formula
of derived contents of the major adsorption minerals and the
correlation.
[0056]
[0057] FIG. 2 is a
flow chart showing a process of a
prediction method of a desorbed gas volume of a shale gas
reservoir using a geophysical logging data analysis of the
present invention.
[0058] As
illustrated in FIG. 2, the prediction method
of the desorbed gas volume of the shale gas reservoir is
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configured to include: a mineral and organic matter content
analysis step S10, a canister gas volume measurement step
S20, a correlation analysis step S30, a major adsorption
mineral content derivation step S40, and a desorbed gas
volume prediction step S50.
[0059] The mineral and organic matter content analysis
step S10 is a process of analyzing minerals and organic
matter by thermal analysis on a shale sample collected from
a borehole by the mineral and organic matter content
analysis part 10. In this process, TOC and kinds and
contents of minerals are analyzed through XRD analysis,
natural gamma radiation, neutron porosity, density,
electrical resistivity, and sonic logging. In addition, the
volume of shale is calculated by using gamma-ray logging and
a combination of neutron porosity and density logging.
[0060] The canister gas volume measurement step S20 is a
process of measuring gas contents by using a gas inside a
canister sealing a collected sample by the canister gas
volume measurement part 20.
[0061] The correlation analysis step S30 is a process
wherein a correlation of the mineral and gas contents is
analyzed by the correlation analysis pert 30, and minerals
having high correlation are extracted as major adsorption
minerals having a large adsorbed gas volume.
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[0062] FIG. 3 depicts graphs each showing a correlation
of one of a combination of minerals inside a collected
sample and a canister gas volume.
[0063] As illustrated in FIG. 3, correlation of canister
volume and various combinations of minerals are derived in
the correlation analysis step S30 by the correlation
analysis part 30, that is, correlations of canister volume
to a clay mineral, canister volume to illite/mica and
smectite, canister volume to illite/mica, canister volume to
illite/smectite, canister volume to kaolinite, canister
volume to chlorite, and so on.
[0064] In the case of FIG. 3, the desorbed gas content
and correlation for each combination of minerals are as
follows.
[0065] 8.966 + 0.743*Volume of Clay minerals R2= 0.442
[0066] 7.748 + 0.971*Volume of Illite/Smectite/Mica R2=
0.537
[0067] 6.317 + 8.534*Volume of Illite/Smectite R2= 0.682
[0068] 8.150 + 1.079*Volume of Illite/Mica R2= 0.510
[0069] 19.47 + 0.982*Volume of Chlorite R2-= 0.034
[0070] 20.90 + 7.996*Volume of Kaolinite R2= 0.442
[0071]
[0072] In the case of FIG. 3, as a result of correlation
analysis, the illite was identified as having the largest
desorbed gas volume and correlation.
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[00731
[0074] With
reference to FIG. 2 again, after deriving
major adsorption minerals having large desorbed gas content
and correlation by performing the correlation analysis step
S30 as described above, contents of the major adsorption
minerals are derived by the major adsorption mineral content
derivation step S40. At this time, to derive a content of
the illite of a major adsorption mineral, a collected sample
is classified into the illite of the major adsorption mineral
W and remainders excluding the illite as a clay mineral. Then,
after substituting major adsorption minerals with the illite,
the content of the illite is derived by a following
interaction formula.
Villite Vsh = psh-Vvh = pclays
pillite-pclays
[0075] , where
Villite is a volume of the illite as the major adsorption
mineral, pillite a density of the illite, pclays a density
of the clay mineral, Vsh a volume of shale, and psh a
density of shale.
[0076]
Subsequently, the desorbed gas volume in the
shale gas reservoir in an investigating area is predicted by
inversely applying correlation of each of a combination of
minerals and the desorbed gas volume in the desorbed gas
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volume prediction step S50 after deriving the content of the
illite as major adsorption mineral.
Industrial Applicability
[0077] The present
invention may be applied to an
industry to develop shale gas resources.
