زمین لرزه 8 خرداد ماه 1383 منطقه فیروزآباد- کجور
براساس تحلیل لرزهنگاشتهای ثبت شده در ایستگاههای باند پهن شبکه لرزهنگاری، پژوهشگاه بینالمللی زلزلهشناسی و مهندسی زلزله، زمینلرزه زیر بوقوع پیوست:
- زمان وقوع زلزله: ساعت 17:08 به وقت محلی
- محل وقوع: شمال غرب بلده به مختصات 51/64 درجه طول جغرافیایی و 36/37 درجه عرض جغرافیایی
- بزرگای: 6.3 =Ms امواج سطحی
- رویداد اصلی در منطقه بلده بلافاصله با پسلرزههای متعددی دنبال گردید که از میان بیش از 200 پسلرزه ثبت شده در شبکه لرزهنگاری باند پهن پژوهشگاه، تعداد حدود 75 پسلرزه که دارای بزرگای بیش از 2 بوده و با دقت خوبی تعیین محل شدهاند، در شکل و جدول زیر نشان داده شدهاند.
- سازوکار تعیین لرزه اصلی دلالت بر گسلش از نوع معکوس دارد که از مشخصههای غالب زمینلرزهها در البرز مرکزی میباشد.
- معرفی گسل یا گسلهای مسبب زمینلرزه اصلی 83/3/8 در منطقه بلده در حال حاضر با توجه به اطلاعات موجود امری دشوار به نظر میرسد. ولی با نگاهی به موقعیت گسلهای البرز مرکزی، روند پسلرزهها و بویژه سازوکار کانونی رویداد اصلی را میتوان به یکی از گسلهای تراستی با روند شمال غرب – جنوب شرق واقع در دامنه شمالی البرز نسبت داده شوند. در این میان فعالیت گسلهای کجور و یا شمال البرز (شکل 2) بعنوان عامل ایجاد رویدادهای اخیر محتملتر بنظر میرسد.
- بدیهی است شناسایی دقیق گسل مسبب زمینلرزه، تعیین ابعاد گسلش و سازوکار کانونی آن پس از بازگشت گروه شناسایی و بررسیهای زمینشناسی و پردازش و تفاسیر دادههای ثبت شده در شبکه لرزهنگاری محلی نصب شده در منطقه میسر خواهد بود.
جدول شماره 1: مشخصات زلزله اصلی و پسلرزهها (Ms امواج سطحی، ML امواج محلی)
| DATE | TIME | LAT-N | LONG-E | DEPTH | mb | Ms | ML | REGION |
| 2004/07/22 | 02:05:32.4 | 36.51 | 51.54 | 28 | 2.9 | BALADEH | ||
| 2004/07/21 | 12:11:48.4 | 36.56 | 51.59 | 15 | 3.2 | BALADEH | ||
| 2004/07/18 | 13:44:19.0 | 36.53 | 51.44 | 28 | 2.8 | BALADEH | ||
| 2004/07/11 | 13:16:48.5 | 36.40 | 51.41 | 28 | 3.3 | BALADEH | ||
| 2004/07/03 | 06:43:31.2 | 36.45 | 51.41 | 15 | 2.9 | BALADEH | ||
| 2004/06/27 | 04:51:35.5 | 36.49 | 51.40 | 12 | 3.3 | BALADEH | ||
| 2004/06/24 | 02:36:28.6 | 36.47 | 51.42 | 28 | 2.8 | BALADEH | ||
| 2004/06/20 | 00:55:02.1 | 36.52 | 51.32 | 29 | 2.2 | BALADEH | ||
| 2004/06/19 | 01:54:41.0 | 36.58 | 51.54 | 28 | 2.4 | BALADEH | ||
| 2004/06/18 | 03:39:50.4 | 36.17 | 51.96 | 28 | 3.3 | BALADEH | ||
| 2004/06/17 | 21:48:19.8 | 36.44 | 51.64 | 28 | 2.3 | BALADEH | ||
| 2004/06/16 | 21:36:40.3 | 36.52 | 51.38 | 28 | 2.0 | BALADEH | ||
| 2004/06/16 | 06:53:26.5 | 36.41 | 51.59 | 28 | 2.4 | BALADEH | ||
| 2004/06/15 | 20:51:35.0 | 36.48 | 51.52 | 28 | 2.2 | BALADEH | ||
| 2004/06/15 | 20:31:43.9 | 36.46 | 51.65 | 28 | 2.2 | BALADEH | ||
| 2004/06/12 | 21:31:01.2 | 36.505 | 51.580 | 28 | 3.5 | BALADEH | ||
| 2004/06/12 | 06:43:42.0 | 36.445 | 51.517 | 28 | 3.3 | BALADEH | ||
| 2004/06/10 | 22:01:14.0 | 36.495 | 51.397 | 28 | 2.1 | BALADEH | ||
| 2004/06/10 | 06:27:23.0 | 36.418 | 51.703 | 28 | 2.7 | BALADEH | ||
| 2004/06/09 | 19:29:46.4 | 36.356 | 51.640 | 28 | 2.4 | BALADEH | ||
| 2004/06/09 | 08:27:03.6 | 36.403 | 51.515 | 28 | 2.8 | BALADEH | ||
| 2004/06/09 | 05:25:18.0 | 36.365 | 51.677 | 28 | 3.0 | BALADEH | ||
| 2004/06/09 | 02:07:33.3 | 36.499 | 51.553 | 28 | 2.3 | BALADEH | ||
| 2004/06/08 | 19:13:10.1 | 36.446 | 51.522 | 28 | 2.2 | BALADEH | ||
| 2004/06/08 | 10:46:24.5 | 36.482 | 51.512 | 28 | 2.7 | BALADEH | ||
| 2004/06/08 | 09:06:08.3 | 36.323 | 51.546 | 28 | 2.8 | BALADEH | ||
| 2004/06/08 | 04:34:36.3 | 36.475 | 51.383 | 28 | 2.5 | BALADEH | ||
| 2004/06/08 | 02:24:46.8 | 36.417 | 51.407 | 28 | 2.4 | BALADEH | ||
| 2004/06/07 | 23:11:59.7 | 36.439 | 51.402 | 28 | 2.2 | BALADEH | ||
| 2004/06/07 | 08:22:18.4 | 36.420 | 51.586 | 28 | 2.4 | BALADEH | ||
| 2004/06/07 | 04:01:23.0 | 36.411 | 51.506 | 28 | 3.9 | BALADEH | ||
| 2004/06/06 | 17:20:15.8 | 36.446 | 51.655 | 28 | 2.8 | BALADEH | ||
| 2004/06/06 | 06:08:21.2 | 36.443 | 51.415 | 28 | 2.8 | BALADEH | ||
| 2004/06/06 | 02:20:10.9 | 36.339 | 51.635 | 28 | 3.3 | BALADEH | ||
| 2004/06/05 | 23:22:38.7 | 36.550 | 51.547 | 28 | 2.3 | BALADEH | ||
| 2004/06/05 | 22:12:45.3 | 36.443 | 51.520 | 28 | 3.0 | BALADEH | ||
| 2004/06/05 | 20:58:14.3 | 36.421 | 51.439 | 28 | 3.2 | BALADEH | ||
| 2004/06/05 | 19:08:48.5 | 36.486 | 51.531 | 28 | 2.5 | BALADEH | ||
| 2004/06/05 | 00:10:45.3 | 36.408 | 51.401 | 28 | 2.8 | BALADEH | ||
| 2004/06/04 | 23:45:05.7 | 36.399 | 51.670 | 28 | 2.4 | BALADEH | ||
| 2004/06/04 | 14:30:31.1 | 36.543 | 51.537 | 45 | 2.8 | BALADEH | ||
| 2004/06/04 | 08:35:21.3 | 36.363 | 51.656 | 28 | 2.5 | BALADEH | ||
| 2004/06/04 | 08:18:53.2 | 36.367 | 51.555 | 28 | 2.4 | BALADEH | ||
| 2004/06/04 | 06:31:37.2 | 36.484 | 51.418 | 28 | 2.3 | BALADEH | ||
| 2004/06/03 | 20:15:25.6 | 36.452 | 51.645 | 28 | 2.8 | BALADEH | ||
| 2004/06/03 | 17:26:11.2 | 36.443 | 51.517 | 28 | 3.5 | BALADEH | ||
| 2004/06/03 | 07:37:27.0 | 36.449 | 51.651 | 28 | 2.5 | BALADEH | ||
| 2004/06/03 | 03:43:45.1 | 36.410 | 51.510 | 28 | 3.0 | BALADEH | ||
| 2004/06/02 | 20:41:19.6 | 36.496 | 51.511 | 28 | 3.1 | BALADEH | ||
| 2004/06/02 | 18:46:24.9 | 36.474 | 51.642 | 28 | 2.2 | BALADEH | ||
| 2004/06/02 | 11:12:25.6 | 36.506 | 51.410 | 28 | 3.0 | BALADEH | ||
| 2004/06/02 | 10:55:27.2 | 36.476 | 51.536 | 28 | 3.4 | BALADEH | ||
| 2004/06/02 | 07:27:32.3 | 36.410 | 51.621 | 6 | 3.5 | BALADEH | ||
| 2004/06/02 | 03:13:36.5 | 36.382 | 51.475 | 28 | 2.2 | BALADEH | ||
| 2004/06/01 | 23:38:09.7 | 36.410 | 51.429 | 28 | 2.0 | BALADEH | ||
| 2004/06/01 | 18:15:47.5 | 36.542 | 51.472 | 28 | 2.4 | BALADEH | ||
| 2004/06/01 | 16:28:34.1 | 36.397 | 51.638 | 33 | 3.2 | BALADEH | ||
| 2004/06/01 | 10:57:46.7 | 36.454 | 51.419 | 28 | 2.7 | BALADEH | ||
| 2004/06/01 | 09:33:15.3 | 36.431 | 51.647 | 28 | 3.5 | BALADEH | ||
| 2004/06/01 | 08:15:20.7 | 36.463 | 51.762 | 33 | 2.6 | BALADEH | ||
| 2004/06/01 | 06:22:01.7 | 36.396 | 51.451 | 28 | 2.6 | BALADEH | ||
| 2004/06/01 | 03:55:12.6 | 36.418 | 51.520 | 28 | 3.3 | BALADEH | ||
| 2004/06/01 | 03:22:26.2 | 36.389 | 51.718 | 28 | 3.2 | BALADEH | ||
| 2004/06/01 | 02:41:28.7 | 36.378 | 51.464 | 28 | 3.3 | BALADEH | ||
| 2004/06/01 | 00:35:32.6 | 36.456 | 51.497 | 28 | 3.2 | BALADEH | ||
| 2004/05/31 | 23:04:42.8 | 36.398 | 51.348 | 28 | 2.0 | BALADEH | ||
| 2004/05/31 | 22:27:01.8 | 36.300 | 51.449 | 15 | 2.2 | BALADEH | ||
| 2004/05/31 | 22:23:25.9 | 36.393 | 51.435 | 28 | 2.2 | BALADEH | ||
| 2004/05/31 | 22:05:34.6 | 36.542 | 51.670 | 12 | 3.3 | BALADEH | ||
| 2004/05/31 | 17:57:00.5 | 36.318 | 51.418 | 34 | 2.1 | BALADEH | ||
| 2004/05/31 | 08:12:16.7 | 36.463 | 51.264 | 14 | 3.7 | BALADEH | ||
| 2004/05/31 | 07:30:29.7 | 36.430 | 51.746 | 26 | 2.3 | BALADEH | ||
| 2004/05/31 | 03:43:38.1 | 36.320 | 51.638 | 15 | 2.4 | BALADEH | ||
| 2004/05/30 | 19:27:02.0 | 36.424 | 51.663 | 10 | 4.6 | BALADEH | ||
| 2004/05/30 | 18:03:19.0 | 36.449 | 51.452 | 28 | 2.7 | BALADEH | ||
| 2004/05/30 | 17:12:01.7 | 36.479 | 51.529 | 28 | 3.1 | BALADEH | ||
| 2004/05/30 | 16:18:24.6 | 36.268 | 51.442 | 28 | 3.2 | BALADEH | ||
| 2004/05/30 | 15:48:46.8 | 36.442 | 51.463 | 28 | 3.5 | BALADEH | ||
| 2004/05/30 | 13:09:55.6 | 36.415 | 51.455 | 28 | 4.0 | BALADEH | ||
| 2004/05/30 | 12:41:41.5 | 36.519 | 51.361 | 28 | 3.1 | BALADEH | ||
| 2004/05/30 | 11:49:02.3 | 36.360 | 51.367 | 28 | 2.8 | BALADEH | ||
| 2004/05/30 | 08:57:06.0 | 36.188 | 51.492 | 28 | 2.9 | BALADEH | ||
| 2004/05/30 | 07:48:53.1 | 36.464 | 51.382 | 28 | 3.5 | BALADEH | ||
| 2004/05/30 | 06:07:36.6 | 36.451 | 51.657 | 28 | 2.9 | BALADEH | ||
| 2004/05/30 | 02:41:27.7 | 36.461 | 51.450 | 28 | 3.6 | BALADEH | ||
| 2004/05/30 | 01:42:41.8 | 36.403 | 51.613 | 28 | 4.5 | BALADEH | ||
| 2004/05/30 | 00:05:17.4 | 36.238 | 51.511 | 7 | 2.7 | BALADEH | ||
| 2004/05/29 | 23:37:51.4 | 36.579 | 51.205 | 43 | 2.9 | BALADEH | ||
| 2004/05/29 | 23:05:46.8 | 36.487 | 51.361 | 28 | 2.6 | BALADEH | ||
| 2004/05/29 | 22:55:19.3 | 36.439 | 51.369 | 28 | 3.9 | BALADEH | ||
| 2004/05/29 | 19:58:19.7 | 36.465 | 51.455 | 28 | 3.5 | BALADEH | ||
| 2004/05/29 | 18:42:45.1 | 36.438 | 51.418 | 28 | 3.8 | BALADEH | ||
| 2004/05/29 | 18:38:07.9 | 36.451 | 51.376 | 28 | 4.6 | BALADEH | ||
| 2004/05/29 | 17:30:26.8 | 36.496 | 51.444 | 28 | 3.9 | BALADEH | ||
| 2004/05/29 | 15:41:03.6 | 36.469 | 51.420 | 28 | 3.9 | BALADEH | ||
| 2004/05/29 | 15:23:49.5 | 36.502 | 51.352 | 28 | 3.3 | BALADEH | ||
| 2004/05/29 | 15:03:49.6 | 36.509 | 51.416 | 28 | 3.2 | BALADEH | ||
| 2004/05/29 | 14:56:46.1 | 36.456 | 51.440 | 28 | 3.7 | BALADEH | ||
| 2004/05/29 | 13:34:24.6 | 36.390 | 51.390 | 28 | 3.3 | BALADEH | ||
| 2004/05/29 | 13:01:55.1 | 36.523 | 51.382 | 28 | 3.4 | BALADEH | ||
| 2004/05/29 | 12:56:43.7 | 36.507 | 51.424 | 28 | 3.6 | BALADEH | ||
| 2004/05/29 | 11:01:32.9 | 36.420 | 51.383 | 28 | 4.2 | BALADEH | ||
| 2004/05/29 | 10:20:40.0 | 36.374 | 51.413 | 28 | 3.6 | BALADEH | ||
| 2004/05/29 | 09:23:51.3 | 36.41 | 51.35 | 28 | 4.7 | BALADEH | ||
| 2004/05/29 | 06:34:14.0 | 36.436 | 51.439 | 28 | 3.2 | BALADEH | ||
| 2004/05/29 | 06:14:20.1 | 36.475 | 51.415 | 28 | 3.4 | BALADEH | ||
| 2004/05/29 | 05:34:50.5 | 36.444 | 51.433 | 28 | 2.8 | BALADEH | ||
| 2004/05/29 | 04:53:04.4 | 36.370 | 51.421 | 28 | 3.7 | BALADEH | ||
| 2004/05/29 | 04:12:35.6 | 36.413 | 51.708 | 28 | 3.9 | BALADEH | ||
| 2004/05/29 | 03:54:27.8 | 36.477 | 51.407 | 28 | 3.3 | BALADEH | ||
| 2004/05/29 | 03:35:23.6 | 36.415 | 51.746 | 28 | 3.5 | BALADEH | ||
| 2004/05/29 | 01:57:58.0 | 36.368 | 51.377 | 28 | 2.9 | BALADEH | ||
| 2004/05/29 | 01:09:57.4 | 36.510 | 51.397 | 9 | 2.8 | BALADEH | ||
| 2004/05/29 | 00:25:48.1 | 36.360 | 51.432 | 28 | 3.4 | BALADEH | ||
| 2004/05/28 | 23:53:57.3 | 36.389 | 51.705 | 28 | 3.1 | BALADEH | ||
| 2004/05/28 | 23:07:27.7 | 36.391 | 51.404 | 28 | 2.6 | BALADEH | ||
| 2004/05/28 | 22:50:37.7 | 36.439 | 51.383 | 28 | 2.4 | BALADEH | ||
| 2004/05/28 | 22:32:34.9 | 36.366 | 51.386 | 28 | 2.6 | BALADEH | ||
| 2004/05/28 | 21:31:25.6 | 36.413 | 51.676 | 28 | 3.1 | BALADEH | ||
| 2004/05/28 | 21:24:47.5 | 36.444 | 51.731 | 15 | 2.9 | BALADEH | ||
| 2004/05/28 | 21:22:48.5 | 36.372 | 51.426 | 28 | 2.5 | BALADEH | ||
| 2004/05/28 | 21:03:35.2 | 36.323 | 51.439 | 28 | 3.5 | BALADEH | ||
| 2004/05/28 | 20:49:25.9 | 36.451 | 51.379 | 28 | 2.8 | BALADEH | ||
| 2004/05/28 | 20:32:57.3 | 36.460 | 51.421 | 28 | 3.3 | BALADEH | ||
| 2004/05/28 | 20:31:20.8 | 36.419 | 51.406 | 28 | 3.2 | BALADEH | ||
| 2004/05/28 | 20:25:31.5 | 36.178 | 51.476 | 28 | 3.4 | BALADEH | ||
| 2004/05/28 | 20:16:55.6 | 36.519 | 51.365 | 28 | 2.7 | BALADEH | ||
| 2004/05/28 | 20:14:29.1 | 36.434 | 51.676 | 28 | 2.6 | BALADEH | ||
| 2004/05/28 | 20:09:18.1 | 36.411 | 51.373 | 28 | 3.1 | BALADEH | ||
| 2004/05/28 | 20:07:26.3 | 36.405 | 51.389 | 28 | 3.2 | BALADEH | ||
| 2004/05/28 | 19:47:05.6 | 36.368 | 51.448 | 28 | 4.8 | BALADEH | ||
| 2004/05/28 | 18:54:50.5 | 36.280 | 51.540 | 15 | 2.5 | BALADEH | ||
| 2004/05/28 | 18:46:36.6 | 36.274 | 51.530 | 15 | 2.3 | BALADEH | ||
| 2004/05/28 | 18:43:38.9 | 36.284 | 51.580 | 15 | 2.3 | BALADEH | ||
| 2004/05/28 | 18:33:13.2 | 36.364 | 51.595 | 15 | 2.7 | BALADEH | ||
| 2004/05/28 | 18:25:04.9 | 36.396 | 51.569 | 33 | 3.1 | BALADEH | ||
| 2004/05/28 | 18:10:19.7 | 36.364 | 51.593 | 15 | 2.3 | BALADEH | ||
| 2004/05/28 | 17:51:21.5 | 36.275 | 51.388 | 15 | 3.2 | BALADEH | ||
| 2004/05/28 | 17:34:51.3 | 36.485 | 51.361 | 22 | 3.3 | BALADEH | ||
| 2004/05/28 | 17:17:26.6 | 36.413 | 51.551 | 23 | 2.8 | BALADEH | ||
| 2004/05/28 | 16:45:21.5 | 36.260 | 51.460 | 28 | 2.8 | BALADEH | ||
| 2004/05/28 | 16:37:51.4 | 36.362 | 51.560 | 35 | 2.0 | BALADEH | ||
| 2004/05/28 | 15:35:05.0 | 36.455 | 51.494 | 28 | 2.4 | BALADEH | ||
| 2004/05/28 | 15:30:26.0 | 36.403 | 51.731 | 9 | 1.7 | BALADEH | ||
| 2004/05/28 | 15:20:49.8 | 36.392 | 51.531 | 28 | 2.6 | BALADEH | ||
| 2004/05/28 | 15:09:09.2 | 36.491 | 51.825 | 28 | 2.6 | BALADEH | ||
| 2004/05/28 | 15:01:18.3 | 36.458 | 51.588 | 26 | 2.5 | BALADEH | ||
| 2004/05/28 | 14:49:53.7 | 36.370 | 51.611 | 15 | 2.6 | BALADEH | ||
| 2004/05/28 | 14:47:51.3 | 36.493 | 51.373 | 10 | 2.8 | BALADEH | ||
| 2004/05/28 | 14:38:29.7 | 36.408 | 51.673 | 15 | 2.5 | BALADEH | ||
| 2004/05/28 | 14:28:27.7 | 36.372 | 51.706 | 28 | 3.0 | BALADEH | ||
| 2004/05/28 | 14:20:22.7 | 36.447 | 51.731 | 20 | 2.8 | BALADEH | ||
| 2004/05/28 | 13:35:56.0 | 36.397 | 51.613 | 28 | 4.4 | BALADEH | ||
| 2004/05/28 | 13:28:43.5 | 36.330 | 51.611 | 15 | 3.0 | BALADEH | ||
| 2004/05/28 | 13:26:28.8 | 36.406 | 51.781 | 15 | 2.9 | BALADEH | ||
| 2004/05/28 | 13:15:07.4 | 36.447 | 51.592 | 37 | 4.6 | BALADEH | ||
| 2004/05/28 | 13:07:11.2 | 36.339 | 51.670 | 28 | 3.9 | BALADEH | ||
| 2004/05/28 | 12:38:46.1 | 36.371 | 51.643 | 28 | 6.3 | BALADEH |
رکوردهای زلزله اصلی

