本文選題：地震勘探 + 環(huán)境噪聲��； 參考：《吉林大學(xué)》2015年碩士論文

【摘要】：陸地地震勘探是煤田和石油勘探中一種重要勘探方法。但是在野外采集過程中，地震資料不可避免的會混入各種噪聲，使有效地震信號淹沒在噪聲中，令資料處理難度加大，也對后續(xù)數(shù)據(jù)的解釋分析造成困擾，直接影響了勘探結(jié)果的準(zhǔn)確性。因此，前人對于地震勘探的研究一直都集中在噪聲的壓制上。 在地震勘探噪聲消減領(lǐng)域，對于噪聲的性質(zhì)一直采用傳統(tǒng)認(rèn)識：線性平穩(wěn)高斯。這是一種理想化的噪聲性質(zhì)，方便于為選擇地震隨機噪聲壓制方法提供理論依據(jù)。然而，在某些情況下基于此思想的去噪方法對實際噪聲的壓制效果并不理想。這就需要對實際噪聲的特性有一個重新的認(rèn)識，向這種理想化的傳統(tǒng)認(rèn)識提出質(zhì)疑與挑戰(zhàn)。 環(huán)境噪聲作為陸地地震勘探隨機噪聲中重要組成成分，目前還沒有被科學(xué)系統(tǒng)的研究過。本文利用時頻峰值濾波中對噪聲高斯性的無偏估計理論，分別就混入高斯白噪和實際純環(huán)境噪聲記錄的模擬地震數(shù)據(jù)進行去噪，通過去噪后的信噪比比較，認(rèn)為實際噪聲具有一定的非高斯特性。同樣利用維納濾波原理對于平穩(wěn)過程的理論要求，進行了高斯白噪和實際純環(huán)境噪聲記錄的去噪仿真實驗，兩者信噪比差異較大，同樣認(rèn)為噪聲的非平穩(wěn)特性存在，確定了噪聲平穩(wěn)性與高斯性檢驗的必要性。 對四個測區(qū)：林帶，沙漠，山地，黃土塬進行了平穩(wěn)性和高斯性的檢驗。其中平穩(wěn)檢驗方法采用基于Fokker-Planck方程的非參數(shù)的平穩(wěn)性檢驗方法，由于考慮到目前濾波算法普遍采用時頻域濾波方法或者針對短時窗內(nèi)局部數(shù)據(jù)濾波，截取數(shù)據(jù)點數(shù)不多，因此對四個測區(qū)的短時噪聲平穩(wěn)性進行檢驗比較及差異分析。結(jié)果表明，各測區(qū)的噪聲均具有非平穩(wěn)性質(zhì)，且各個測區(qū)間非平穩(wěn)情況不同。為此進一步分析噪聲局部平穩(wěn)性情況，實驗結(jié)果認(rèn)為噪聲是可以進行局部分段平穩(wěn)研究的。 應(yīng)用四種常用的正態(tài)檢驗方法：SW檢驗，KS檢驗，，Lilliefors檢驗，JB檢驗進行蒙特卡羅實驗，最后選取檢驗功效最優(yōu)的SW檢驗方法作為實際噪聲高斯性檢驗方法。對不同測區(qū)不同長度的高斯性進行比較。檢驗結(jié)果表明，非高斯情況隨著沙漠，黃土塬，山地，林帶依次減弱，但是當(dāng)數(shù)據(jù)長度足夠長時，四個測區(qū)的實際地震數(shù)據(jù)都顯現(xiàn)出極大非高斯特性。 本文的主要研究方向是對陸地地震勘探環(huán)境噪聲的特性進行檢驗，其中特性主要包括平穩(wěn)性與高斯性。通過系統(tǒng)研究不同地區(qū)不同長度純環(huán)境噪聲紀(jì)錄，對陸地地震勘探環(huán)境噪聲特性研究進行了補充，為今后噪聲建模、依據(jù)噪聲性質(zhì)去噪提供理論依據(jù)。
[Abstract]:Land seismic exploration is an important exploration method in coalfield and petroleum exploration. However, in the process of field acquisition, the seismic data will inevitably be mixed with various noises, which will make the effective seismic signal submerged in the noise, make the data processing more difficult, and also cause trouble to the interpretation and analysis of the subsequent data. It directly affects the accuracy of exploration results. Therefore, previous researches on seismic exploration have been focused on noise suppression. In the field of noise abatement in seismic exploration, the character of noise has been traditionally recognized: linear stationary Gao Si. This is an idealized noise property, which is convenient to provide a theoretical basis for the selection of seismic random noise suppression methods. However, in some cases, the denoising method based on this idea is not effective in suppressing actual noise. Therefore, it is necessary to have a new understanding of the characteristics of actual noise and challenge this idealized traditional understanding. As an important component of random noise in terrestrial seismic exploration, environmental noise has not been studied by scientific system. In this paper, the unbiased estimation theory of noise Gao Si in time-frequency peak filtering is used to Denoise the simulated seismic data mixed with the actual pure ambient noise, and the signal-to-noise ratio (SNR) after denoising is compared. It is considered that the actual noise has some non-Gao Si characteristics. At the same time, according to the theoretical requirements of Wiener filtering principle for stationary process, the simulation experiments of Gao Si white noise and real pure ambient noise record are carried out. The signal-to-noise ratio between them is quite different, and the non-stationary characteristic of noise is also considered to exist. The necessity of noise smoothness and Gao Si test is determined. The stability and Gao Si of four survey areas: forest belt, desert, mountain and loess tableland were tested. Among them, the stationary test method is based on the Fokker-Planck equation. Considering that the current filtering algorithms generally use time-frequency filtering method or local data filtering in the short-time window, the number of truncated data points is not large. Therefore, the short-time noise stationarity of the four measuring areas is tested and compared and the differences are analyzed. The results show that the noise of each measuring area is nonstationary and the non-stationary condition is different in each interval. The experimental results show that the noise can be studied by local piecewise stationary analysis. In this paper, four normal test methods are used: KS test and Lilliefors test / JB test to carry out Monte Carlo experiment. Finally, the optimal SW test method is selected as the actual noise Gao Si test method. Gao Si of different length in different measuring area was compared. The results show that the non- situation weakens in turn with the desert, loess plateau, mountain and forest belt, but when the length of the data is long enough, the actual seismic data of the four measured areas show a great non- characteristic. The main research direction of this paper is to test the characteristics of environmental noise in terrestrial seismic exploration, and the characteristics mainly include stationarity and Gao Si. By systematically studying the pure environmental noise records of different regions and different lengths, this paper supplements the research on environmental noise characteristics of land seismic exploration, and provides theoretical basis for noise modeling and denoising based on noise properties in the future.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P631.4

【參考文獻】

相關(guān)期刊論文 前10條

1 聶鵬飛;曾謙;馬海濤;李月;林紅波;;消減地震勘探隨機噪聲:導(dǎo)數(shù)算子約束下的維納濾波[J];吉林大學(xué)學(xué)報(地球科學(xué)版);2010年06期

2 李月;馬海濤;林紅波;趙曉京;楊泉;宋蕾;;基于核函數(shù)主分量的維納濾波方法研究[J];地球物理學(xué)報;2010年05期

3 田小平，丁玉美;利用多項式擬合模板法消除地震數(shù)據(jù)中的低頻隨機干擾[J];地球物理學(xué)報;1996年S1期

4 陳國民;沈章洪;鮑祥生;張金淼;;確定合成地震記錄子波主頻的方法研究[J];石油天然氣學(xué)報;2009年05期

5 向馗;蔣靜坪;;時間序列的非平穩(wěn)度分析[J];科技通報;2007年01期

6 方衛(wèi)東;懷博;;滬深300指數(shù)馬氏性檢驗及預(yù)測[J];科學(xué)技術(shù)與工程;2011年20期

7 房林;鄒衛(wèi)星;;多種單位根檢驗法的比較研究[J];數(shù)量經(jīng)濟技術(shù)經(jīng)濟研究;2007年01期

8 項靜恬,杜金觀,王文玉;時間序列非線性門限模型——模擬非平穩(wěn)動態(tài)數(shù)據(jù)的一種有效工具[J];數(shù)學(xué)的實踐與認(rèn)識;1985年02期

9 李慶忠;;關(guān)于低信噪比地震資料的基本概念和質(zhì)量改進方向[J];石油地球物理勘探;1986年04期

10 劉貴忠,宗濤,章珂,鄒大文,錢俊生,李鳳歧;利用縱向小波包變換和橫向多項式擬合提高地震信號的信噪比和分辨率[J];石油地球物理勘探;1995年05期

本文編號：1856417