CN109683196A - A kind of ionosphere and seismic precursor correlative space-time characterisation analysis method - Google Patents
A kind of ionosphere and seismic precursor correlative space-time characterisation analysis method Download PDFInfo
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- CN109683196A CN109683196A CN201811357573.4A CN201811357573A CN109683196A CN 109683196 A CN109683196 A CN 109683196A CN 201811357573 A CN201811357573 A CN 201811357573A CN 109683196 A CN109683196 A CN 109683196A
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- 239000005433 ionosphere Substances 0.000 title claims abstract description 36
- 238000004458 analytical method Methods 0.000 title claims abstract description 21
- 239000002243 precursor Substances 0.000 title claims abstract description 17
- 238000012512 characterization method Methods 0.000 title claims abstract description 12
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
- G01V1/30—Analysis
- G01V1/307—Analysis for determining seismic attributes, e.g. amplitude, instantaneous phase or frequency, reflection strength or polarity
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
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Abstract
A kind of ionosphere and seismic precursor correlative space-time characterisation analysis method, the data of detecting link are received based on the oblique survey station in ionosphere, the ionospheric critical frequency at observation link midpoint is obtained using inverting, utilize hyperspace reconstructing method, obtain ionospheric critical frequency Spatial Variation, and Ionospheric variability Study on Trend is as a result, this result can be analyzed for anomalous of the ionosphere, seismic precursor analysis provides basis.
Description
Technical field
The invention belongs to seismic precursor analysis field more particularly to a kind of ionosphere and seismic precursor correlative space-time characterisations
The method of analysis.
Background technique
Seismic precursor forecast is the sciences problems that the current whole world faces.Ionosphere is capable of providing clearly seismic precursor and rings
It answers.In order to promote the development of omen Earthquake Prediction Research, many scientists constantly explore the new method of seismological observation and forecast,
Wherein using before earthquake anomalous of the ionosphere phenomenon and earthquake Ionosphere coupling theory to study earthquake prediction become current
One of hot spot.
In recent years, increasing with ionospheric observatory point, the development of global positioning system inversion technique, and it is related
The use of satellite is monitored, scientists have observed that the ionospheric data before and after more macroseisms carries out analysis to these data and grinds
Study carefully, it has been found that Ionospheric Parameters are disturbed before a variety of shakes, such as electron concentration, and critical frequency, virtual height, electron concentration always contain
Ultralow frequency, very low frequencies etc. in amount, ion concentration temperature and ionosphere electromagnetic radiation background.Barnes (nineteen sixty-five) is 1964
When year Alaska violent earthquake, there is the generation of disturbing phenomenon in discovery ionosphere, and this observation and analysis is seemingly sent out for the first time
There is certain relevance between the two in the disturbance in existing ionosphere and the generation of earthquake【1】.Use ionization within Pulinets (1998) later
The diurnal variation of the critical frequency, maximum electron concentration NmF2 and layer height of layer visualizer analysis Ionospheric F_2-layer, finds in 1979-
Before the several macroseisms occurred in 1981, these Ionospheric Parameters are with the presence of disturbance, and wherein foF2 can reduce extremely, and height can be abnormal
Increase【2】.Pulinets (1998) is but abnormal the study found that floor anomalous of the ionosphere area with the position of focal area is corresponding
Peak point be not overlapped with the subpoint in earthquake centre, the diameter of the exceptions area disturbed is probably magnitude, and sometimes different
Normal perturbing area can also be observed in the magnetic conjugated region of another corresponding hemisphere【3】.Compare on the November 8th, 1997 of Ma Buddhist nun 7.5
Grade and 8.1 grades of preceding magnetic fields of earthquake of West Kunlun Mountains Pass on November 14th, 2001 and anomalous of the ionosphere distribution and feature, the results show that two
The secondary preceding magnetic field of Giant Bullous and ionosphere Impending anomaly spatial-temporal distribution characteristic have preferable consistency, occur day variation around earthquake centre
Often, it is obviously abnormal to there is ionosphere foF2 for Lhasa platform【4】.3 days before Wenchuan earthquake (May 9), Chongqing ionosphere occurs great different
Often, foF2 is obviously increased, and amplitude is very big, about more than the 3 of background reference values times【5】【6】.Kunming foF2 is first 3 days (May 9), preceding
2 days (May 10) also obviously increases, and amplitude is also very big【7】【8】.Show ionospheric critical frequency foF2 caused by seismic activity
Variation be implicitly present in.JY Liu et al. people in 2004 analyzes 1994 ~ 1999 years totally 184 M > 5.0 grade earthquake foF2 before shake
Situation of change, discovery shake preceding 5 days in foF2 reduction percentage be more than 25%, with the increase seismo-ionospheric anomaly feelings of earthquake magnitude
Condition is gradually significant, it was demonstrated that the ionospheric disturbance occurred before earthquake occurs may be related to earthquake【9】。
Further to study omen Earthquake Prediction Research, while the related data in ionosphere is made full use of, is badly in need of using one
The effective method of kind is anomalous of the ionosphere and seismic precursor for analyzing the space-time characterisation in ionosphere Yu seismic precursor correlative
Analysis provides basis.
Bibliography
【1】Leonard R S, Jr R A B. Observation of ionospheric disturbances
following the Alaska earthquake[J]. Journal of Geophysical Research, 1965, 70
(5):1250–1253.
【2】PULINETS S A,LEGENKA A D,KARPACHEV A T.The earthquakes prediction
possibility on the base of topside sounding data[J]. 1991,34a(981):25.
【3】Pulinets S A, Legenka A D, Zelenova T I. Local-Time Dependence of
Seismo-Ionospheric Variations at the F-Layer Maximum[J]. Geomagnetism &
Aeronomy, 1998, 38(3):400-402.
[4] earth's magnetic field Ding Jianhai, Suo Yucheng, Yu Surong is empty with anomalous of the ionosphere phenomenon and its with relationship [J] of earthquake
Between scientific journal, 2005,25 (6): 536-542.
[5] Ding Zonghua, Wu Jian, Sun Shuji, with waiting variation characteristic and analysis [J] of the preceding ionosphere parameter of Wenchuan earthquake
Ball Acta Physica Sinica, 2010,53 (1): 30-38.
[6] Seismo-Ionospheric Anomalies of Wu Jian, Xu Tong, the Hu Yanli based on the vertical measured data in national electric wave observation network ionosphere
Progress [J] earthquake journal, 2016,38 (3): 345-355.
[7] Ionospheric Profile reconstruct and the spatial abnormal feature research Xi'an [D] electronic section that Guo Wanzhen is detected based on ground wave
Skill university, 2011.
[8] He Jianhui, Zhang Xuemin, Lin Jian, wait Wenchuan earthquake with shake ionospheric disturbance research [J] earthquake, 2017,37
(2):126-134.
【9】Liu J Y, Chuo Y J, Shan S J, et al. Pre-earthquake ionospheric
anomalies registered by continuous GPS TEC measurements[J]. Annales
Geophysicae, 2004, 22(5):1585-1593。
Summary of the invention
In order to solve the problems existing in the prior art, the invention proposes a kind of ionospheres and seismic precursor correlative space-time characterisation point
Ionospheric critical frequency time change and spatial characteristics can be obtained using the method in analysis method, provides and grinds for earthquake prediction
Study carefully basis.
A kind of ionosphere with seismic precursor correlative space-time characterisation analysis method be it is realized through the following technical scheme,
Include:
Step A: the locality maximum usable frequency data of the oblique incidence souding link of seismoelectric absciss layer observational network；
Step B: detection data pretreatment removes abnormal data using tenths method, calculates data intermediate value；
Step C: the parameter in refutation process, including conversion factor, gyro-frequency and transmission factor are determined；
Step D: determining ionosphere distance using the longitude and latitude between two websites, calculates weight using amendment Kriging method, most
Regional restructuring is carried out using this result and critical frequency inversion result afterwards；
Step E: Ionospheric Parameters time and spatial character are calculated using the interpretation of result that inverting and reconstruct obtain.
Further, step C is specifically described as follows:
Step C1: rule of thumb formula determines conversion factor using the transmission range between detection site；
Step C2: the reference value of the gyro-frequency based on six grades of spheric harmonic function geomagnetic field model calculation path midpoints；
Step C3: delay estimation M (3000) F is corresponded to using basic MUF2；
Step C4: critical frequency inverting is carried out.
Further, step D is specifically described as follows:
Step D1: ionosphere distance is calculated using the geographic latitude and longitude between two websites；
Step D2: weight is calculated using reconstruct equation group；
Step D3: the ionosphere parameter foF2 in unknown place is calculated using the above results.
Further, step E is specifically described as follows:
Step E1: analyze Ionospheric Parameters round the clock, season and with solar activity variation characteristic；
Step E2: utilizing grid contour tracing algorithm, calculates the spatial contour distribution of Ionospheric Parameters.
The present invention is based on the data that the oblique survey station in ionosphere receives detecting link, obtain observation link midpoint using inverting
Ionospheric critical frequency obtains ionospheric critical frequency Spatial Variation and ionosphere using hyperspace reconstructing method
Changing trend analysis is as a result, this result can be analyzed for anomalous of the ionosphere, seismic precursor analysis provides basis.
Detailed description of the invention
Attached drawing 1 is flow diagram of the present invention；
Attached drawing 2 is step C " critical frequency inverting " flow diagram；
Attached drawing 3 is step D " regional restructuring " flow diagram；
Attached drawing 4 is step E " space-time characterisation analysis " flow diagram.
Specific embodiment
The key step in the present invention is briefly described below according to drawings and examples.
Step A: the locality maximum usable frequency data of the oblique incidence souding link of seismoelectric absciss layer observational network；
Step B: data prediction removes abnormal data using tenths method, calculates data intermediate value；
Step C: critical frequency inverting is carried out:
For being less than 4000km detecting link, ray communication theory inverting critical frequency is utilized；
Step C1: conversion factor is determined:
Step C2: path midpoint gyro-frequency is determined:
In formula,FRepresent earth's magnetic field；
Step C3: the F of analysis path midpoint2Layer 3000km transmission factor M (3000) F2:
In formula,τFor the corresponding time delay of basic MUF, a0For earth radius,dFor propagation distance,cFor the light velocity；
Step C4: critical frequency is carried out based on above-mentioned parameter:
Step D: the regional restructuring of Ionospheric Parameters is carried out using amendment Kriging interpolation method；
Step D1: defining ionosphere distance isd ij :
WhereinWithIt respectively indicatesi、jThe geographic logitude and latitude stood,cIt is correlation distance scale factor, takes
1.4；
Step D2: weight is calculated using reconstruct equation group:
Step D3: the Kriging estimator of unknown point is calculated:
With the measured value foF2 of multiple ionosphere observation points i (i=1,2 ... n)Calculate the ionosphere parameter foF2 in unknown place:
Step E: Ionospheric Parameters time and spatial character are calculated using the interpretation of result that inverting and reconstruct obtain:
Step E1: analyze Ionospheric Parameters round the clock, season and with solar activity variation characteristic；
Step E2: grid contour tracing algorithm is utilized, the spatial distribution of Ionospheric Parameters is calculated.
Claims (4)
1. a kind of ionosphere and seismic precursor correlative space-time characterisation analysis method, it is characterised in that: concrete scheme includes:
Step A: the locality maximum usable frequency data of the oblique incidence souding link of seismoelectric absciss layer observational network；
Step B: detection data pretreatment removes abnormal data using tenths method, calculates data intermediate value；
Step C: the parameter in refutation process, including conversion factor, gyro-frequency and transmission factor are determined；
Step D: determining ionosphere distance using the longitude and latitude between two websites, calculates weight using amendment Kriging method, most
Regional restructuring is carried out using this result and critical frequency inversion result afterwards；
Step E: Ionospheric Parameters time and spatial character are calculated using the interpretation of result that inverting and reconstruct obtain.
2. a kind of ionosphere and seismic precursor correlative space-time characterisation analysis method according to claim 1, it is characterised in that:
Step C is specifically described as follows:
Step C1: rule of thumb formula determines conversion factor using the transmission range between detection site；
Step C2: the reference value of the gyro-frequency based on six grades of spheric harmonic function geomagnetic field model calculation path midpoints；
Step C3: delay estimation M (3000) F is corresponded to using basic MUF2；
Step C4: critical frequency inverting is carried out.
3. a kind of ionosphere and seismic precursor correlative space-time characterisation analysis method according to claim 1, it is characterised in that:
Step D is specifically described as follows:
Step D1: ionosphere distance is calculated using the geographic latitude and longitude between two websites；
Step D2: weight is calculated using reconstruct equation group；
Step D3: the ionosphere parameter foF2 in unknown place is calculated using the above results.
4. a kind of ionosphere and seismic precursor correlative space-time characterisation analysis method according to claim 1, it is characterised in that:
Step E is specifically described as follows:
Step E1: analyze Ionospheric Parameters round the clock, season and with solar activity variation characteristic；
Step E2: utilizing grid contour tracing algorithm, calculates the spatial contour distribution of Ionospheric Parameters.
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Cited By (5)
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| CN110673206A (en) * | 2019-08-26 | 2020-01-10 | 吉林大学 | Satellite magnetic field data earthquake abnormity detection method based on non-negative matrix factorization |
| CN110995381A (en) * | 2019-11-26 | 2020-04-10 | 天津大学 | Short-wave wireless transmission available frequency prediction method |
| CN111008361A (en) * | 2019-11-26 | 2020-04-14 | 天津大学 | Ionosphere parameter reconstruction method |
| CN113109632A (en) * | 2021-04-08 | 2021-07-13 | 三门峡职业技术学院 | Method for inverting F2 layer parameters by using oblique ionogram |
| CN113325469A (en) * | 2020-02-28 | 2021-08-31 | 中国科学院国家空间科学中心 | Seismic ionized layer TEC correlation analysis method |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110673206A (en) * | 2019-08-26 | 2020-01-10 | 吉林大学 | Satellite magnetic field data earthquake abnormity detection method based on non-negative matrix factorization |
| CN110673206B (en) * | 2019-08-26 | 2020-12-29 | 吉林大学 | Satellite magnetic field data earthquake abnormity detection method based on non-negative matrix factorization |
| CN110995381A (en) * | 2019-11-26 | 2020-04-10 | 天津大学 | Short-wave wireless transmission available frequency prediction method |
| CN111008361A (en) * | 2019-11-26 | 2020-04-14 | 天津大学 | Ionosphere parameter reconstruction method |
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| CN113325469A (en) * | 2020-02-28 | 2021-08-31 | 中国科学院国家空间科学中心 | Seismic ionized layer TEC correlation analysis method |
| CN113325469B (en) * | 2020-02-28 | 2023-10-13 | 中国科学院国家空间科学中心 | Earthquake ionized layer TEC correlation analysis method |
| CN113109632A (en) * | 2021-04-08 | 2021-07-13 | 三门峡职业技术学院 | Method for inverting F2 layer parameters by using oblique ionogram |
| CN113109632B (en) * | 2021-04-08 | 2023-04-14 | 三门峡职业技术学院 | Method for inverting F2 layer parameters by using oblique ionogram |
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