We review the current knowledge of the Pleistocene Modern Chiapanecan Volcanic Arc (MCVA). This arc is related to the subduction of the Cocos plate beneath the North American plate in the State of Chiapas, southeastern Mexico. The MCVA consists of large intrusive bodies, domes, eroded volcanic landforms, and the active El Chichón, which produced the disastrous 1982 eruption, the deadliest in Mexico’s recorded history. The available geological knowledge, and new geological and aeromagnetic data on the arc, reveals a system composed of a sizeable intrusive body called the Santa Fe diorite, and small-size volcanoes such as El Chichón and Catedral, and extinct volcanoes associated with volcaniclastic deposits. A 3D-inversion of the aeromagnetic anomalies indicates that the Santa Fe diorite is a large intrusive body (27 km long, 4 km wide with a minimum volume of 1662 km 3 ) while small volcanoes such as El Chichón have small-size magma chambers (~ 7 km 3 ). Interestingly, our models of the causative bodies for the aeromagnetic anomalies suggest that the El Chichón volcano, as well as of other volcanic areas in the region, are not linked directly to the Santa Fe intrusive. However, new 40 Ar/ 39 Ar dates for samples from the Santa Fe intrusive (2.2 Ma), the Catedral volcano (1.6 Ma), and a mafic enclave (1.09 Ma) hosted in 1982 Chichón deposits, along with the aeromagnetic anomalies and geochemical data confirm that these extrusive and intrusive structures belong to the MCVA. The chemistry of these structures suggests that magmas generated in the upper mantle by the subduction system evolved through different processes, such as crustal contamination for the Santa Fe diorite and Catedral volcano, and crystal fractionation for El Chichón volcano.

中文翻译：

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奇琼火山区（墨西哥）下的圣达菲侵入体和其他岩浆体：来自航磁和新岩石地质年代学数据的推论

我们回顾了更新世现代恰帕尼卡火山弧 (MCVA) 的当前知识。该弧与墨西哥东南部恰帕斯州北美板块下方的科科斯板块俯冲有关。MCVA 由大型侵入体、圆顶、被侵蚀的火山地貌和活跃的 El Chichón 组成，该火山产生了 1982 年灾难性的火山喷发，这是墨西哥有记录以来最致命的火山喷发。现有的地质知识以及有关该弧的新地质和航磁数据揭示了一个系统，该系统由一个称为圣达菲闪长岩的大型侵入体、El Chichón 和 Catedral 等小型火山以及与火山碎屑沉积物相关的死火山组成。航磁异常的 3D 反演表明圣达菲闪长岩是一个大型侵入体（27 公里长，4 公里宽，最小体积为 1662 公里 3 ），而像 El Chichón 这样的小火山有小尺寸的岩浆房（~ 7 km 3 ）。有趣的是，我们的航磁异常原因体模型表明，El Chichón 火山以及该地区其他火山区与 Santa Fe 侵入体没有直接联系。然而，新的 40 Ar/ 39 Ar 日期来自 Santa Fe 侵入岩 (2.2 Ma)、Catedral 火山 (1.6 Ma) 和 1982 年 Chichón 矿床的镁铁质飞地 (1.09 Ma)，以及航空磁异常和地球化学数据证实这些挤压和侵入结构属于 MCVA。这些结构的化学性质表明，俯冲系统在上地幔中产生的岩浆通过不同的过程演化，