中国地震台网【 1 】的速报地震震级为 M s 6.6 级,美国地震台网【 2 】报的是 M w 5.9 级,地震局地质所郭志先生【 3 】通过震源机制解给出的震级为 M w 6.47 级,地震局地球物理研究所【 4 】的震源机制解反演结果为 M w 6.1级 。 我们的预测结果【 5 】为 M s 5.9-6.5 级。上限 M s 6.5 级是如何确定的呢?是根据新一轮孕育周期内积累的应变能反算得出的结果, 且考虑锁固段膨胀点标志性地震震级与峰值强度点地震震级的关系,综合判定的结果。 如此看来,中国地震台网的速报震级值确实报高了,估计会修订。 那么,该震的震级定为多大合适呢?在我看来,定为 M s 6.1-6.5 级间的某个值较为合理。 Wells 等 (1994) 【 6 】的研究也已表明:在 5.7-8.0 级之间,矩震级与面波震级之间没有系统偏差。 换句话说,在此范围内,不管采用 M s 或是 M w 震级标度,两者应相等或相差不大。 参考 【1 】 http://data.earthquake.cn/datashare/datashare_details_subao.jsp?id=CC20130722075506 【2 】 http://earthquake.usgs.gov/earthquakes/eventpage/usb000ije3#summary 【3 】 http://www.eq-igl.ac.cn/admin/upload/files/20130722Dingxi.pdf 【4 】 http://www.cea-igp.ac.cn/upload/Image/mrtp/tpxw/2013n/20130722gsdxds/2674188375.jpg 【5 】 http://blog.sciencenet.cn/home.php?mod=spaceuid=575926do=blogid=710240 【 6 】 Wells D L andCoppersmith K J . 1994 . New empiricalrelationships among magnitude , rupture length,rupture width , rupture area and surface displacement . Bull Seism Soc Am , 84(4) : 974- 1002 .
当前震级标度有以下几种:地方性震级 M L , 短周期体波震级 m b 、长周期体波震级 m B 、面波震级 M S 、矩震级 M W 以及持续时间震级 M D ,常见震级标度换算公式如下: 对于 M W 震级的转换采用以下方法,在大多数破坏性地震的震级测定中,当 6.4 < M S < 7.8 时, M W = M S ;当 M S = 6 时, M W ≈ M S ,相差很小;在较小震级范围内 M W = M L 。 震级 M L 、地震矩 M 0 、地震能量 E 和 Benioff Strain 之间换算关系如下: 当不同的震级标度统一换算为 M L 时,表 1 给出了震级及相应的能量、 Benioff 应变值。 表 1 震级 - 能量 - Benioff 应变换算表 震级 ( M L ) 地震距 M 0 能量 E Benioff 应变 1 3.55E+10 1.77E+06 1.33E+03 2 1.12E+12 5.61E+07 7.49E+03 3 3.55E+13 1.77E+09 4.21E+04 4 1.12E+15 5.61E+10 2.37E+05 5 3.55E+16 1.77E+12 1.33E+06 6 1.12E+18 5.61E+13 7.49E+06 7 3.55E+19 1.77E+15 4.21E+07 8 1.12E+21 5.61E+16 2.37E+08 9 3.55E+22 1.77E+18 1.33E+09
印度尼西亚发生7.4级地震 http://www.sina.com.cn 2010年09月30日01:49 新华网 图中A点即为地震发生点。(4.920S, 133.783E) 新华网快讯:据印尼气象与地球物理局消息,印度尼西亚东部巴布亚地区30日凌晨发生里氏7.4级强烈地震。 http://news.sina.com.cn/w/2010-09-30/014921198280.shtml GFZ Potsdam GEOFON Global Seismic Monitor GFZ Potsdam - Earthquake Bulletin This real-time bulletin is a product of the GEOFON Extended Virtual Network (GEVN) and credit belongs to all involved institutions! Disclaimer: Unless revised by a geophysicist, automatically determined earthquake locations may be erroneous! This bulletin is customizable and also available as RSS news feed. New search Legend Origin Time UTC Mag Latitude degrees Longitude degrees Depth km A M Region Name 2010-09-29 21:03:26 5.0 4.84 S 133.74 E 10 A Irian Jaya Region, Indonesia 2010-09-29 20:28:06 4.5 4.94 S 133.70 E 83 A Irian Jaya Region, Indonesia 2010-09-29 20:08:11 5.0 7.16 S 123.11 E 605 A Banda Sea 2010-09-29 19:06:51 5.2 7.34 S 129.14 E 144 C Banda Sea 2010-09-29 18:52:12 4.1 36.16 N 23.04 E 10 A Southern Greece 2010-09-29 18:49:33 5.9 15.51 S 172.26 W 10 M Samoa Islands Region 2010-09-29 18:35:02 5.0 47.69 N 153.75 E 90 A Kuril Islands 2010-09-29 18:00:54 5.2 5.36 S 133.95 E 37 A Aru Islands Region, Indonesia 2010-09-29 17:30:03 6.4 2.81 N 46.99 W 10 C North Atlantic Ocean 2010-09-29 17:11:27 7.1 5.07 S 133.87 E 10 M Aru Islands Region, Indonesia 2010-09-29 17:10:52 7.2 4.93 S 133.80 E 10 M Irian Jaya Region, Indonesia 2010-09-29 16:29:54 5.5 34.71 S 71.54 W 74 A Near Coast of Central Chile 2010-09-29 14:10:46 4.2 2.83 N 128.61 E 226 A Halmahera, Indonesia 2010-09-29 11:33:32 5.1 5.07 N 94.70 E 44 A Northern Sumatra, Indonesia 2010-09-29 08:00:01 5.7 37.23 N 139.97 E 37 M Eastern Honshu, Japan 2010-09-29 04:22:26 5.4 28.68 N 134.77 E 61 A West of Bonin Islands 2010-09-29 04:14:47 5.3 36.78 S 176.92 E 283 M Off E. Coast of N. Island, N.Z. http://geofon.gfz-potsdam.de/db/eqinfo.php 2010-09-29 20:35:18.4 44min ago 37.98 N 20.73 E 5 ML 2.8 IONIAN SEA 2010-09-29 20:38 2010-09-29 20:08:11.2 1hr 11min ago 7.21 S 123.09 E 614 M 5.1 BANDA SEA 2010-09-29 20:15 2010-09-29 20:00:29.0 1hr 19min ago 40.71 N 30.12 E 7 MD 3.1 WESTERN TURKEY 2010-09-29 20:15 2010-09-29 19:23:31.0 1hr 56min ago 39.00 N 24.06 E 6 ML 2.5 AEGEAN SEA 2010-09-29 19:35 2010-09-29 19:06:48.9 2hr 13min ago 7.41 S 129.22 E 155 M 5.4 KEPULAUAN BABAR, INDONESIA 2010-09-29 21:09 2010-09-29 18:52:08.7 2hr 28min ago 36.36 N 23.28 E 2 ML 3.8 SOUTHERN GREECE 2010-09-29 19:01 2010-09-29 18:49:38.8 2hr 30min ago 15.77 S 172.10 W 60 mb 5.4 SAMOA ISLANDS REGION 2010-09-29 20:41 2010-09-29 18:41:55.0 2hr 38min ago 46.37 N 12.80 E 5 ML 2.0 NORTHERN ITALY 2010-09-29 18:49 2010-09-29 18:34:57.9 2hr 45min ago 47.82 N 153.91 E 60 mb 4.7 KURIL ISLANDS 2010-09-29 19:49 2010-09-29 17:10:51.3 4hr 09min ago 4.90 S 133.82 E 10 Mw 6.7 NEAR S COAST OF PAPUA, INDONESIA 2010-09-29 17:32 2010-09-29 16:44:02.4 4hr 36min ago 37.60 N 38.71 E 5 MD 3.1 EASTERN TURKEY 2010-09-29 17:07 2010-09-29 16:39:42.9 4hr 40min ago 39.92 N 36.31 E 8 MD 3.0 CENTRAL TURKEY http://www.emsc-csem.org/index.php