Crustal movements detected by GPS observations before and after the India ocean earthquake of M9.3 in 2004 and other earthquakes
-
摘要: 2004年至2012年印尼西部海域发生多次大地震，其中2004年印度洋9.3级巨震为本世纪以来全球最强。利用印尼及其邻近区域35个GPS连续观测站和中国大陆北京附近的GPS连续观测站BJFS站全球参考框架坐标时间序列，可得到以BJFS作为核心站的区域参考框架下这些站大地震震前位移积累、同震和震后位移，特别是震前水平位移积累和同震水平位移。该区大地震时空间隔密，且分布范围较大，观测站相互间与地震相关的地壳运动影响明显，地壳运动极为复杂。本文重点讨论了5次8级以上大地震前后地壳运动的特点、成因和相互影响。GPS观测结果显示，研究区域内7.5级以上地震的同震水平位移是震前水平位移积累的（弹性）回跳，震前水平位移积累是前兆。9.3级与2005年8.7级地震震级与时空相近，有重合与不重合的前兆形变区，是前者触发后者的主要条件。而9.3级与8.7级震后强烈地壳水平运动与2012年8.6和8.2级地震的发生直接有关。2007年的8.4级地震的发生与9.3和8.7级地震无明显关系，但其震后水平位移影响了赤道南8.6和8.2级地震的同震水平位移。尽管所采用的GPS连续观测站数量少、密度低，但仍为研究地震预测中多次地震前后地壳运动的复杂性提供了有意义的震例。研究表明，印尼西部地区是全球最有意义的地震预测探索区之一。Abstract: From 2004 to 2012, multiple strong earthquakes occurred offshore western part of Indonesia and among them the Indian Ocean earthquake of M9.3 in 2004 has been the greatest in this century in the world. Based on the time series of coordinates at 35 stations of continuous GPS observations in Indonesia and its neighborhood in the global reference frame, the accumulated preseismic, coseismic and post seismic displacements, particularly the accumulated preseismic horizontal displacements and the coseismic horizontal displacements of these earthquakes in the regional reference frame with the core station at BJFS near Beijing on China mainland, are obtained. The crustal movements in the region has been quite complicated as shown by significant mutual influences in the crustal movements that were related at the GPS observation stations because of strong earthquakes of short time intervals and short spacing, scattering over a large area. The features, causes and mutual influences of the preseismic, coseismic and postseismic crustal movements of 5 earthquakes of magnitudes over 8.0 are discussed. Results of GPS observations show that the coseismic horizontal displacements of earthquakes of magnitudes larger than 7.5 were (elastic) rebound of the accumulated preseismic horizontal displacements, which were precursory to the earthquakes. The M9.3 in 2004 and M8.7 in 2005 were close in magnitudes, occurrence time and spacing and the areas of anomalous crustal deformations in the preparation of both events were both overlapping and non overlapping, which was the prerequisite for the triggering of the latter by the former event. The intensive post seismic horizontal crustal movements of the M9.3 and M8.7 earthquakes significantly contributed to the occurrence of the M8.6 and M8.2 earthquakes in 2012. Though the occurrence of the M8.4 earthquake was independent of the M9.3 and M8.7 earthquakes, the postseismic horizontal crustal movements of the M8.4 influenced the coseismic horizontal displacements of the M8.6 and M8.2 earthquakes, south to the equator. Though stations of continuous GPS observations used in this study is small in number and low in density, they have accumulated valuable earthquake cases of complicated crustal deformations before and after multiple strong earthquakes with GPS observations for the benefit of exploring earthquake predictions. The study shows that the western part of Indonesia is one of the most valuable areas for the exploration of earthquake predictions in the world.
-
图 1 印尼西部近海及其邻近区域的大地震（大红点）及GPS连续观测站（彩色点）。图右侧为表示GPS观测站大地高的色码。标有站名的为本文采用的35个GPS连续观测站，其中10个站文中显示位移时间序列，站名标为红色。震级标记为棕色的3次地震未作研究
Figure 1. Large earthquakes (big red dots) and GPS stations of continuous observations (small color dots) offshore and in the western part of Indonesia. On the right side is the color code for the geodetic heights at the GPS stations. 35 GPS stations of continuous observations used in the paper are marked with station codes, 10 of them with displacement time series shown in the paper are marked with station codes in red. Earthquakes marked with magnitudes in brown are not studied in the paper
图 2 印尼西部近海多次大地震同震水平（左图）与垂直（右图）位移。各图左下角为位移向量或位移比例尺
Figure 2. Coseismic horizontal displacements (left figure) and vertical displacements (right figure) of the large earthquakes offshore the western part of Indonesia. The displacement (vector) scale is shown at the bottom left of each figure
图 3 印尼西部海域多次大地震附近多个GPS连续观测站3个位移分量和水平位移向量时间序列，位移单位均为mm。左图为3个分量，即水平位移东西（E，棕色）和南北（N，红色）分量与垂直（U，蓝色）位移时间序列，图上方标出了有明显同震位移的地震震级。右图为水平位移向量时间序列，图右侧为用GPS周表示日期的色码。
Figure 3. Time series of 3 displacement components (left figure) and horizontal displacement vectors (right figure) in mm at several stations of continuous GPS observations in the western part of Indonesia. The 3 displacement component are the east horizontal component E in brown, north horizontal component N in red and vertical component U in blue. At the top of the figures of 3 displacement components, the magnitudes of the earthquakes are shown. On the right side of each vector figure the color code shows the date in GPS week for time series of the horizontal displacement vectors
图 4 GPS连续观测站NGNG的3个位移分量和水平位移向量时间序列，位移单位均为mm。左图为3个分量，即水平位移东西（E，棕色）和南北（N，红色）分量与垂直（U，蓝色）位移时间序列，图上方标出了有明显同震位移的地震震级。右图为水平位移向量时间序列，图右侧为用GPS周表示日期的色码。上图和下图时间段不同
Figure 4. Time series of 3 displacement components (left figure) and horizontal displacement vectors (right figure) in mm at the station NGNG of continuous GPS observations. The 3 displacement component are the east horizontal component E in brown, north horizontal component N in red and vertical component U in blue. At the top of the figures of 3 displacement components, the magnitudes of the earthquakes are shown. On the right side of each vector figure the color code shows the date in GPS week for time series of the horizontal displacement vectors. The upper and lower figures are different in time periods
表 1 2004至2012年印尼西部近海多次大地震日期、震级和位置
Table 1. Dates, magnitudes and locations of earthquakes offshore western Indonesia from 2004 to 2012
日期 GPS周 震级 震中经纬度和震源深度 2004-12-26 1303 日 9.3 E96.0°，N3.3°，30.0 km 2005-03-28 1316 一 8.7 E97.0°，N2.1°，30.0 km 2005-04-10* 1318 日 6.7 E99.607°，S1.644°，19.0 km 2007-09-12
相距225 km1444 三 8.4
7.9E101.5°，S4.4°，34.0 km
E100.841°，S2.625°，35.0 km2008-02-20* 1467 三 7.4 E95.964，N2.768，26.0 km 2008-02-25 1468 一 7.6 E99.972°，S2.486°，25.0 km 2009-08-16* 1545 日 6.7 E99.490°，S 1.479°，20.0 km 2009-09-30* 1551 三 7.6 E99.867°，S0.720°，81.0 km 2010-04-07 1578 三 7.8 E97.1°，N2.4°，46.0 km 2010-05-09* 1583 日 7.2 E96.018°，N3.748°，38.0 km 2010-10-25 1607 一 7.7 E100.082°，S3.478°，20.0 km 2012-04-11
相距183 km1683 三 8.6
8.2E93.1°，N2.3°，20.0 km
E92.4°，N0.8°，20.0 km注：表中8.4级地震中国地震台网测定的震级为7.9级。以下分别用6b7和7b6表示2008月2月25日6.7级和2009年9月30日7.6级地震。表中日期后的标记*，表示地震附近仅有一个GPS连续观测站有显著的同震和震前水平位移。给出了同一天2次地震的距离。 
下载: 导出CSV
表 2 印尼西部海域多次大地震多个GPS连续观测站的震中距与同震水平位移
Table 2. Epicentral distances and coseismic horizontal displacements of stations of continuous GPS observations for several earthquakes offshore western Indonesia from 2004 to 2012
地震 站名代码 震中距
km同震水平位移
mm站名代码 震中距
km同震水平位移
mm站名代码 震中距
km同震水平位移
mm9.3 SAMP 319 142.4 PBAI 475 4.8 BSAT 861 8 PSMK 438 26.7 NGNG 681 3.7 NTUS 896 18.5 8.7 LEWK 172 129.4 PBAI 282 51.5 NGNG 492 8.5 SAMP 247 180.3 ABGS 327 47.5 NTUS 735 11.3 PSMK 255 788.9 UMLH 383 192.7 PTLO 270 163.2 MSAI 437 15.4 8.6+8.2 LEWK 309 280.9 LHW2 464 74.2 BTHL 547 32.2 BNON 340 214.1 PBLI 479 105 SDKL 569 85.6 UMLH 393 154.8 HNKO 498 47.4 8.4+7.9 LAIS 113（166） 726.7 SLBU 245（94） 221.1 TIK1 475 73 BSAT 199（80） 1471.3 PPNJ 339（154） 698.3 NTUS 680 25.5 PRKB 200（62） 1798.4 NGNG 380 161.7 ABGS 736 18.7 MKMK 210（29） 792.7 JMBI 381 81.1 LNNG 237（51） 605.4 PSKI 384 256.6 7.8 PBLI 41 325.2 SAMP 230 14.9 7.7 BSAT 71 348.6 KTET 138 71.7 LNNG 200 20.2 PRKB 88 186.8 PKRT 167 35.9 NGNG 213 16.1 SLBU 94 302.4 MKMK 175 26.2 TRTK 244 14.5 SMGY 112 142.9 PPNJ 182 26.4 7.608年 KTET 18 125.4 SLBU 41 213.8 BSAT 81 8.7 SMGY 26 99.2 PPNJ 63 15.5 NGNG 105 9.4 7.609年 ABGS 90 20.5 NGNG 296 39.9 PKRT 328 20.8 MSAI 253 55.1 PPNJ 310 22.3 注：震中距一栏中括号内为2次地震中后一次地震的震中距。表中2008年7.6级地震NGNG站同震水平位移是利用地震前后相隔相对较久的观测结果估计得的。
下载: 导出CSV
-
[1] 顾国华. GPS-地震预测利器 [M]//白春礼. 科学与中国（十年辉煌 光耀神州）: 气候与灾害科学技术集. 北京: 北京大学出版社, 2012Gu G H. GPS-Useful technique for earthquake prediction[M]//Bai C L. Science and China: Science and technology for climate and disasters. Beijing: Peking University Press, 2012 [2] Gu G H,Wang W X. Advantages of GNSS in monitoring crustal deformation for detection of precursors to strong earthquakes[J]. Positioning,2013,4:11-19 doi: 10.4236/pos.2013.41003 [3] Blewitt G,Corné K,Hammond W C,et al. Terrestrial reference frame NA12 for crustal deformation studies in North America[J]. Journal of Geodynamics,2013,72:11-24 doi: 10.1016/j.jog.2013.08.004 [4] 顾国华,王武星,占伟,等. 东日本 MW9.0 大地震前、同震及震后地壳水平运动[J]. 武汉大学学报(信息科学版),2015,40(12):1669-1676Gu G H,Wang W X,Zhan W,et al. Preseismic,coseismic and postseismic horizontal crustal movements of the MW9.0 Tohoku earthquake in 2011 in Japan[J]. Geomatics and Information Science of Wuhan University,2015,40(12):1669-1676 [5] 顾国华、王武星. 2016年日本本州近海MS7.2地震前后的地壳运动[J]. 地震学报,2020,42(2):196-204 doi: 10.11939/jass.20190096GU G H,Wang W X. Crustal Movements of the MS7.2 Honshu Offshore Earthquake in 2016 in Japan[J]. Acta Seismologica Sinica,2020,42(2):196-204 doi: 10.11939/jass.20190096 [6] 顾国华,王武星. GPS观测得到的大地震前兆地壳形变震例[J]. 地震科学进展,2020,50(10):30-39GU G H,Wang W X. Case Studies on GPS Observations and Crustal Deformation Precursors to Strong Earthquakes[J]. Progress in Earthquake Sciencess,2020,50(10):30-39 [7] Kreemer C,Blewitt G,Hammond W C,et al. Global deformation from the great 2004 Sumatra-Andaman earthquake observed by GPS:Implications for rupture process and global reference frame[J]. Earth Planets Space,2006,58:141-148 doi: 10.1186/BF03353370 [8] 顾国华,王武星. GPS观测到的智利及其邻区多次大地震前后地壳运动[J]. 地震科学进展,2022,52(5):222-231 doi: 10.19987/j.dzkxjz.2021-086Gu G H,Wang W X. Crustal movements before and after several earthquakes in Chile and its neighborhood detected by GPS observations[J]. Progress in Earthquake Sciences,2022,52(5):222-231 doi: 10.19987/j.dzkxjz.2021-086 [9] 顾国华. 青海玛多7.4级和门源6.9级地震GPS观测结果[M]//地震预测咨询委文集（2022）. 待出版Gu G H. Results of GPS observations of the M7.4 Madu and M6.9 Menyuan earthquakes in Qinhai, China[M]// 2022 Collection of Papers of the Earthquake Forecasting Consultative Board. In Press [10] 顾国华,王武星. GPS测得的2018年夏威夷6.9级地震与火山喷发地壳运动[J]. 武汉大学学报(信息科学版),2019,44(8):1191-1204Gu G H,Wang W X. Crustal Motions Observed from GPS observations for the Earthquake of M6.9 and the Eruption of the Kilauea Volcano in 2018[J]. Geomatics and Information Science of Wuhan University,2019,44(8):1191-1204 [11] Blewitt G,Hammond W C,Kreemer C. Harnessing the GPS data explosion for interdisciplinary science[J]. Eos Transactions American Geophysical Union,2018:99 [12] Wessel P,Smith W H. New version of the generic mapping tools released[J]. Eos Transactions American Geophysical Union,1995,76(47):329 -
点击查看大图
计量
- 文章访问数: 20
- HTML全文浏览量: 15
- PDF下载量: 12
