CN106530628A - Three-index joint early warning method for micro-earthquake large-magnitude event - Google Patents

Three-index joint early warning method for micro-earthquake large-magnitude event Download PDF

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CN106530628A
CN106530628A CN201611105416.5A CN201611105416A CN106530628A CN 106530628 A CN106530628 A CN 106530628A CN 201611105416 A CN201611105416 A CN 201611105416A CN 106530628 A CN106530628 A CN 106530628A
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microseism
cbs
time
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CN106530628B (en
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董陇军
张凌云
李夕兵
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Central South University
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    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
    • G08B21/02—Alarms for ensuring the safety of persons
    • G08B21/10—Alarms for ensuring the safety of persons responsive to calamitous events, e.g. tornados or earthquakes

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Abstract

The invention discloses a three-index joint early warning method for a micro-earthquake large-magnitude event, which comprises the steps of installing a micro-earthquake monitoring system in a target area, acquiring the time, the amplitude and the frequency of a micro-earthquake, automatically calculating the time, the frequency, energy and the moment magnitude of an earthquake source micro-earthquake activity in the target area, and performing statistics to acquire accumulated Benioff strain, a b-value and an H-index of the earthquake source micro-earthquake activity in the target area; drawing a time sequence diagram of the three indexes such as the accumulated Benioff strain, the b-value and the H-index is drawn, variation trends of the three indexes such as the accumulated Benioff strain, the b-value and the H-index are analyzed, predicting whether a micro-earthquake large-magnitude event occurs or not according to the variation trends of the three indexes, and predicting mine rock disaster and accidents through performing early warning on the micro-earthquake large-magnitude event.

Description

A kind of three index combined pre-warning methods of the big earthquake magnitude event of microseism
Technical field
The invention belongs to micro seismic monitoring early warning technology field, is related to a kind of pre- police of many reference amounts of the big earthquake magnitude event of microseism Method.
Background technology
In recent years, with the increase year by year of China's mining depth, mining area rock burst, ore deposit are shaken, collapse etc., and rock mass disaster is got over Come more serious, but carry out early warning to which and be always a global problem, many mines all introduce Microseismic monitoring system, its Effect is also barely satisfactory.According to statistics, most rock mass disaster accidents are all accompanied by the big earthquake magnitude event of microseism, therefore, it can lead to Cross the big earthquake magnitude event of early warning microseism to carry out rock body quality of mine disaster early warning, but there is no at present is carried out to the big earthquake magnitude event of microseism The method of early warning.
Therefore, it is necessary to design a kind of big earthquake magnitude event method for early warning of microseism.
The content of the invention
The technical problem to be solved is, for the deficiencies in the prior art, there is provided a kind of big earthquake magnitude event of microseism Three index combined pre-warning methods, calculate simplicity, strong applicability, accuracy height.
The technical solution of the present invention is as follows：
A kind of three index combined pre-warning methods of the big earthquake magnitude event of microseism, comprise the steps：
Step one：Microseismic monitoring system is installed in target area；Using Microseismic monitoring system collection the microseism time, amplitude and Frequency the automatically time of calculating target area focus microseismic activity, the frequency, energy and moment magnitude；
Step 2：At set intervals, CBS values, the b values of setting time window region of interest within focus microseismic activity are counted With H indexes (Hurst indexes)；
Wherein, CBS values represent the accumulation Benioff strain of target area focus microseismic activity, equal to a time window The sum of interior Benioff strain value；Before most of earthquake, accumulation Benioff strain rate of release increases (i.e. CBS values increase), Therefore can be using accumulation Benioff strain as the big earthquake magnitude event warning index of microseism；
Constant of the b values of microseismic activity for sign seismic events relative moment magnitude distribution；When b values first increase to be subtracted afterwards, represent Might have the big earthquake magnitude event of microseism to occur；
The H indexes of microseismic activity are by entering to setting time window region of interest within focus microseismic activity time serieses T (t) Row R/S analyses are obtained；
H indexes are a kind of Time series analysis methods for being proposed by Hurst first, are widely used in a point shape research, due to Microseismic activity shows the fractal property of self similarity in many aspects, before a large amount of microseismic event data analyses find big earthquake magnitude event H indexes are more than 0.5, therefore H indexes are applied to the big earthquake magnitude event early warning of microseism；
Step 3：The variation tendency of the CBS values, b values and H indexes of analysis target area focus microseismic activity；Then will be micro- The CBS values of shake activity, b values, the variation tendency of H indexes press following logic value：CBS value increases are designated as 1, and other situations are designated as 0； After b values first increase, write-off is 1, and other situations are designated as 0；H-number is designated as 1 more than 0.5, and other situations are designated as 0, as shown in table 1；
The big earthquake magnitude event early warning logical table of 1 microseism of table
Finally, the variation tendency value of CBS values, b values, H indexes is designated as into three digits, and according to three digits for obtaining Judged, early warning microseism big earthquake magnitude event when this three digit that and if only if is 111.
In the step 2, Benioff strain value BS is calculated by the empirical equation of following moment magnitude M：
Accumulation Benioff strain (CBS values) is equal to the sum of Benioff strain value in a time window, CBS=∑s BS。
In the step 2, the b values of microseismic activity pass through the statistical relationship of following B.Gutenberg and C.F.Richter Formula and method of least square are calculated：
Lgn (M)=a-bM
Wherein, M is earthquake moment magnitude；N (M) is the moment magnitude that occurs in setting time window of target area in interval (M ± Δ M) in earthquake number of times；A is constant, for characterizing setting time window region of interest within seismic activity level；
Change the value of seismic moment magnitude M, obtain point (M, lgn (M)) in plane right-angle coordinate, recycle least square Method is calculated b values.
In the step 2, the calculating process of the H indexes of microseismic activity is as follows：
One group of setting time window region of interest within focus microseismic activity time serieses T (t) is recorded, adjacent two are calculated Focus microseismic activity time interval, obtains new time serieses ξ (t)：
ξ (t)=T (t+1)-T (t) t=1,2,3 ..., n
By sequence ξ (t) according to being divided into scale length for XIndividual subsequence；For m-th subsequence, note ξ (t, m) (t=1,2,3 ..., X；M=1,2,3 ..., Y) it is its t-th sample elements, rememberFor its average, R is rememberedmFor its pole Difference, remembers SmFor its standard deviation；Note scale length is (R/S) for the rescaled range of XX；Calculate successively as followsRm、SmWith (R/S)X：
Hurst is analyzing the ratio (R/S) of extreme difference and standard deviationNFind just like ShiShimonoseki with during the statistical law of scale yardstick N It is formula：
(R/S)X=(α X)H
Wherein, α is statistical constant, and H is Hurst indexes.Above formula take the logarithm obtain scale length for X when H indexes：
lg(R/S)X=H lgX+H lg α；
Change the value of scale yardstick X, obtain point (lgX, lg (R/S) in plane right-angle coordinateX), using least square Method is calculated final H indexes.
In the step 3, first according to different time, CBS values, the b of the target area focus microseismic activity for obtaining are counted Value and H indexes；Draw CBS values, b values, the time series chart of three indexs of H indexes；Then CBS is obtained according to time series chart Value, b values, the variation tendency of three indexs of H indexes.
When history of existence training sample data, imitated with the early warning under setting time length of window according to different intervals Rate, determines the interval time in step 2 and setting time length of window using early warning efficiency highest principle.
When no history training sample data, the default interval time is 7 days, and setting time length of window is 1 month.
Beneficial effect：
Microseismic monitoring system, collection microseism time, amplitude and frequency are installed in target area, and calculate automatically target area The time of focus microseismic activity, the frequency, energy and moment magnitude, the accumulation Benny that statistics obtains target area focus microseismic activity are difficult to understand Husband (Beniof) strain, b values and H indexes；Draw out accumulation Benioff strain, b values, the time serieses of three indexs of H indexes Figure, analysis accumulation Benioff strain, b values, the variation tendency of three indexs of H indexes, according to the variation tendency of three indexs, in advance Whether survey occurs the big earthquake magnitude event of microseism, predicts rock body quality of mine disaster thing by carrying out early warning to the big earthquake magnitude event of microseism Therefore.It is high that the present invention calculates simplicity, strong applicability, accuracy.
Description of the drawings
Fig. 1 is CBS value time series charts；
Fig. 2 is b value time series charts；
Fig. 3 is H exponential time sequence chart；
Fig. 4 is 3 index conjoint analysis early warning figures.
Specific embodiment
Illustrate with reference to the Historical Monitoring data of certain ore deposit.
Step one：The time of the part focus microseismic activity that the Microseismic monitoring system installed from mine is obtained, earthquake magnitude, the frequency Table.
Step 2：Acquiescence took setting time window for 1 month, and sliding step-length is 7 days, calculated Benny Austria husband of microseismic activity Strain, the accumulation Benioff strain for counting microseismic activity are to be added the Benioff strain in its 1 month (4 week)； B values, H indexes (H indexes are both greater than 0.5 in table) are calculated using method of least square, statistics obtains 3 fingers on 13-October of July 11 , wherein there is big earthquake magnitude event in August 20 days and October 8 in mark time serieses such as following table.
Time B values H indexes BS values CBS values
July 13 1.12 1.11 33 /
July 19 0.90 0.84 105 /
July 26 0.60 0.91 204 /
August 3 days 0.72 0.76 451 793
August 9 days 0.72 0.73 349 1110
August 16 days 0.68 0.72 509 1513
August 23 days 0.89 0.78 532 1842
August 30 days 0.83 0.94 146 1537
September 6 days 1.00 0.87 26 1213
September 13 days 0.91 1.01 11 715
September 20 days 1.06 0.65 1668 1851
September 27 days 0.96 0.80 1170 2875
October 4 0.92 0.84 118 2967
October 11 0.81 0.75 2145 5101
Step 3：The accumulation Benioff strain CBS values of analysis microseismic activity, b values, the change of three indexs of H indexes become Gesture；
First according to different time, CBS values, b values and the H indexes of the target area focus microseismic activity for obtaining are counted；Paint The accumulation Benioff strain CBS values of microseismic activity processed, b values, the time series chart of three indexs of H indexes, as shown in Figures 1 to 3；
Then obtain the accumulation Benioff strain CBS values of microseismic activity, b values, H indexes three according to time series chart to refer to Target variation tendency.
As illustrated, all there is the rising of CBS values, b values and first rising to October 11 within 13rd in July 26 to August 16 days, September Drop, H indexes are more than 0.5 afterwards, meet the pattern of early warning 111, open the early warning to big earthquake magnitude event；Actually in August 20 days and There is big earthquake magnitude event in October 8 (time point as shown in Fig. 4 arrows), illustrate that the present invention has preferably carried out the big earthquake magnitude of microseism Event early warning.

Claims (7)

1. three index combined pre-warning methods of the big earthquake magnitude event of a kind of microseism, it is characterised in that comprise the steps：
Step one：Microseismic monitoring system is installed in target area；Using Microseismic monitoring system collection microseism time, amplitude and frequency And calculate automatically time, the frequency, energy and the moment magnitude of target area focus microseismic activity；
Step 2：At set intervals, CBS values, b values and the H of setting time window region of interest within focus microseismic activity are counted Index；
Wherein, CBS values represent the accumulation Benioff strain of target area focus microseismic activity, equal to shellfish in setting time window The sum of Ni Aofu strain values；
Constant of the b values of microseismic activity for sign seismic events relative moment magnitude distribution；
The H indexes of microseismic activity are by carrying out R/ to setting time window region of interest within focus microseismic activity time serieses T (t) S analyses are obtained；
Step 3：The variation tendency of the CBS values, b values and H indexes of analysis target area focus microseismic activity；Then microseism is lived Dynamic CBS values, b values, the variation tendency of H indexes press following logic value：CBS value increases are designated as 1, and other situations are designated as 0；B values After first increasing, write-off is 1, and other situations are designated as 0；H-number is designated as 1 more than 0.5, and other situations are designated as 0, as shown in table 1；
The big earthquake magnitude event early warning logical table of 1 microseism of table
Finally, the variation tendency value of CBS values, b values, H indexes is designated as into three digits, and is carried out according to three digits for obtaining Judge, early warning microseism big earthquake magnitude event when this three digit that and if only if is 111.
2. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to claim 1, it is characterised in that the step In rapid two, Benioff strain value BS is calculated by the empirical equation of following moment magnitude M：
B S = 5 × 10 1.5 × ( M + 6.06 ) - 5 .
3. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to claim 2, it is characterised in that the step In rapid two, the b values of microseismic activity pass through the statistic relation and method of least square of following B.Gutenberg and C.F.Richter Calculate：
Lg n (M)=a-bM
Change the value of seismic moment magnitude M, obtain point (M, lg n (M)) in plane right-angle coordinate, recycle method of least square It is calculated b values；
Wherein, M is earthquake moment magnitude；N (M) is the moment magnitude that occurs in setting time window of target area in interval (M ± Δs The number of times of the earthquake in M)；A is constant, for characterizing setting time window region of interest within seismic activity level.
4. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to claim 3, it is characterised in that the step In rapid two,
The calculating process of the H indexes of microseismic activity is as follows：
Record setting time window region of interest within focus microseismic activity time serieses T (t), calculates two adjacent focus microseisms Active time interval, obtains new time serieses ξ (t)：
ξ (t)=T (t+1)-T (t) t=1,2,3 ..., n
By sequence ξ (t) according to being divided into scale length for XIndividual subsequence；For m-th subsequence, note ξ (t, M) (t=1,2,3 ..., X；M=1,2,3 ..., Y) it is its t-th sample elements, rememberFor its average, R is rememberedmFor its extreme difference, note SmFor its standard deviation；Note scale length is (R/S) for the rescaled range of XX；Calculate successively as followsRm、Sm(R/ S)X：
ξ m ‾ = 1 X Σ t = 1 X ξ ( t , m )
R m = max k = 1 , 2 , ... , X Σ t = 1 k ( ξ ( t , m ) - ξ m ‾ ) - min k = 1 , 2 , ... , X Σ t = 1 k ( ξ ( t , m ) - ξ m ‾ )
S m = [ 1 X Σ t = 1 X ( ξ ( t , m ) - ξ m ‾ ) 2 ] 1 2
( R / S ) X = 1 Y Σ m = 1 Y R m S m
H indexes when scale length is X are calculated finally according to below equation：
lg(R/S)X=H lg X+H lg α；
Change the value of scale yardstick X, obtain point (lgX, lg (R/S) in plane right-angle coordinateX), using method of least square meter Calculation obtains final H indexes.
5. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to claim 1, it is characterised in that the step In rapid three, first according to different time, CBS values, b values and the H indexes of the target area focus microseismic activity for obtaining are counted；Draw CBS values, b values, the time series chart of three indexs of H indexes；Then CBS values, b values, H indexes three are obtained according to time series chart The variation tendency of index.
6. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to any one of Claims 1 to 5, its feature It is, when history of existence training sample data, according to the early warning efficiency under different intervals and setting time length of window, The interval time in step 2 and setting time length of window is determined using early warning efficiency highest principle.
7. three index combined pre-warning methods of the big earthquake magnitude event of microseism according to any one of Claims 1 to 5, its feature It is that when no history training sample data, the default interval time is 7 days, and setting time length of window is 1 month.
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CN108798785A (en) * 2018-06-06 2018-11-13 中煤能源研究院有限责任公司 A kind of coal mine rock burst prediction and warning method
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CN109507728A (en) * 2018-11-08 2019-03-22 长沙矿山研究院有限责任公司 A kind of underground hazard method for early warning based on micro seismic monitoring
CN109441546A (en) * 2018-12-28 2019-03-08 湖北海震科创技术有限公司 Method based on microseism information mine disaster auto-partition early warning
CN110942593A (en) * 2019-10-23 2020-03-31 中南大学 Three-index early warning method and system for large-earthquake-level fault slippage event
CN110942593B (en) * 2019-10-23 2020-10-20 中南大学 Three-index early warning method and system for large-earthquake-level fault slippage event
CN113253344A (en) * 2021-05-12 2021-08-13 中油奥博(成都)科技有限公司 Method for realizing pressure raising early warning of underground gas storage based on microseism monitoring technology
CN113253344B (en) * 2021-05-12 2022-04-22 中油奥博(成都)科技有限公司 Method for realizing pressure raising early warning of underground gas storage based on microseism monitoring technology
CN113657044A (en) * 2021-07-30 2021-11-16 深圳市中金岭南有色金属股份有限公司凡口铅锌矿 Ore body large-seismic-level event early warning method and device, terminal equipment and medium

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