Tertiary Magmatic Evolution of the Maricunga Mineral Belt in Chile
Tertiary Magmatic Evolution of the Maricunga Mineral Belt in Chile
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DOI：
10.1080/00206819409465506
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发表时间：
1994-12
影响因子：
2.6
通讯作者：
S. Kay;C. Mpodozis;A. Tittler;P. Cornejo
中科院分区：
文献类型：
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作者：
S. Kay;C. Mpodozis;A. Tittler;P. Cornejo
智利北方安第斯山脉中南部岩浆前缘沿着晚渐新世-早中新世火山活动与马里昆加矿带（南纬28°至26°）低温热液金银矿床的形成有关。岩浆活动开始于约26 Ma，并持续到2006 Ma，当火山前缘向东迁移。带内中心的演化反映了与中安第斯山脉剧烈构造变化相关的地壳增厚，这种构造变化是由于纳斯卡板块俯冲改变了形状，并导致上覆地壳和岩石圈地幔发生了变化。在这些变化中，有南部“板块”火山活动的停止和东部普纳高原的隆起。在这种背景下，马里昆加带岩浆活动可以被看作是在五个岩浆构造幕。第一个是晚渐新世至早中新世（26至20 Ma）的一幕，在此期间，火山杂岩在一个适度倾斜的俯冲带上爆发，通过一个45 km-t.
Late Oligocene-Early Miocene volcanic activity along the magmatic front of the south Central Andes in Northern Chile was associated with the formation of epithermal gold-silver deposits in the Maricunga mineral belt (28° S to 26° S). Magmatic activity began at approximately 26 Ma and lasted until ∼ 6 Ma, when the volcanic front migrated eastward. The evolution of the centers within the belt reflects crustal thickening associated with the dramatic tectonic changes in the Central Andes that occurred as the subducting Nazca plate changed shape and caused modifications in the overlying crust and lithospheric mantle. Among these changes were the cessation of volcanism in the “flat-slab” to the south and the uplift of the Puna plateau to the east. Within this setting, Maricunga-belt magmatism can be viewed in five magmatic-tectonic episodes. The first was a Late-Oligocene to Early-Miocene (26 to 20 Ma) episode, during which volcanic complexes erupted over a moderately dipping subduction zone through a ∼ 45-km-t...