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跨墨西哥火山带是一个由弧内扩展断层网络变形而形成的活动火山弧。长度为14km、最大落差为260m的莫雷利亚断层是位于这个火山弧中部的主要正断层,也是一个36km长的断裂组合的一部分,在主断层面测量的擦痕线表明其具有次级左旋分量的南北张性倾向滑动。在莫雷利亚断层上盘出露良好的横断面,位于主要的断层迹几米处有两个土壤埋层,包含陶瓷碎片和石器,放射性碳测年表明,二者形成的时间分别为公元420~660年(前哥伦布古典时期,Chupícuaro文化)和公元1290~1435年(古典时代后期)。下伏基岩(阿特夸罗熔结凝灰岩)由三个综合次级正断层切割成阶梯状,从而形成两个塌积的楔形。可以从该部分推断出三个滑移事件,其位移范围在46~185cm之间(平均109cm)。这些事件中的最近一次必定发生在公元1290~1435年之后,在古典时代后期或可能在novohispanic时期早期。莫雷利亚断层能够产生M W6~7地震,对人口超过900 000的莫雷利亚地区产生的危害主要有地震地面震动危害和局部地表断层破裂危害。在莫雷利亚断层上发生的7次一系列小型地震的震源位于城镇中心下方,深度为11km,断层迹穿越了城市居民区。此外,在历史地震期间,该镇曾多次遭受严重的地震动。最好的记录是1858年6月19日的地震,此次地震造成莫雷利亚大范围的破坏,对应于修正的麦卡利烈度表上的VIII-IX烈度。在线材料放射性碳分析报告,1894~1904年和1909~1911年的地方地震目录
Across the Mexican volcanic belt is an active volcanic arc formed by the deformation of the extended fault network within the arc. The Morelia Fault, with a length of 14 km and a maximum drop of 260 m, is the main normal fault located in the middle of this volcanic arc and also part of a 36 km long fault combination. The scored line measured on the main fault plane indicates that it has a secondary left- The north-south tension component tends to slip. There are two soil burial layers, including ceramic fragments and stone tools, located a few meters above the main fault trace on the upper plate of the Morelia fault revealing a good cross section dating from AD 420 ~ 660 years (pre-Columbian period, Chupícuaro culture) and AD 1290 ~ 1435 (late classical period). The underlying bedrock (Attalco Melting Tuff) is cut into three steps by a synthetic secondary normal fault, forming two collapsed wedges. Three slip events can be inferred from this section, with a displacement range of 46-185 cm (109 cm on average). The last of these events must occur after 1290 to 1435 AD, late in the classical period or perhaps early novohispanic period. The Morelia fault can generate M6.6 ~ 7 earthquakes. The damage to the Morelia region with a population of more than 900,000 is mainly caused by the earthquake ground vibration damage and the local surface fault rupture. The source of a series of seven small earthquakes that hit the Morelia Fault lies below the center of the town at a depth of 11 km and traces the passage of urban settlements. In addition, the town has suffered many serious earthquakes during the historical earthquake. The best record was the earthquake of June 19, 1858, which caused extensive damage to Morelia and corresponds to VIII-IX intensities on the revised McCulier scale. Online Material Radiocarbon Analysis Report, Local Earthquake Catalogs, 1894-1904 and 1909-1911