Contrasting tectonic and magmatic signatures of convergent margin magmas associated with porphyry Cu versus iron oxide-copper-gold deposits

铜和金是工业和社会上重要的金属，通常从矿床中提取 形成于板块边缘的聚合，可以在南美洲和北美洲的西部科迪勒拉山脉发现， 包括在加拿大。斑岩型Cu±Mo±Au和氧化铁-铜-金矿床是这类矿床的两个重要类型 矿床（IOCG）有相似之处，但也有重要的差异，并且通常不会在时间上同时出现 和空间.这两种存款类型都可能与岩浆喷出的热液流体有关， 大致相似的过程。然而，大多数当前的研究将存款类型视为不相关的， 不同的，有时高度对比的成矿模式。 在智利，斑岩和IOCG矿床出现在靠近但不重叠的位置。优秀的曝光和 这一地区构造历史的良好约束允许对这些地质背景进行高水平的控制， 存款我们对已发表数据的初步评估表明， 地球化学可以观察到，这与记录的构造环境的变化。 在这个提议中，我们的目标是通过使用矿物， 锆石、磷灰石和Fe-Ti氧化物，以提供对氧、硫和水的逸度的限制。我们将 检验这两种不同的岩浆之间的主要差异之一， 存款类型是它们的硫含量，而硫含量又反映了不同的岩浆来源和熔融条件。 更好地理解有助于形成的对比构造和岩浆环境 斑岩和IOCG矿床将为此类矿床的勘探提供信息，并限制对此类矿床的勘探， 加拿大科迪勒拉山脉等地区。

Copper and gold, industrially and societally important metals, are commonly extracted from ore deposits formed at convergent plate margins, and can be found in the western Cordilleras of South and North American, including in Canada. Two important classes of such deposits, porphyry Cu±Mo±Au and iron oxide-copper-gold deposits (IOCG) have similarities but also important differences, and do not typically occur together in time and space. Both deposit types can be related to hydrothermal fluids exsolved from magmas, and seem to form by broadly similar processes. However, most current research treats the deposit types as unrelated, with distinct, and sometimes highly contrasting models for ore formation. In Chile, porphyry and IOCG deposits occur in close but not overlapping proximity. Excellent exposure and the well-constrained tectonic history of this region permit a high level of control on the geological context of these deposits. Our preliminary assessment of published data indicates that clear but subtle differences in their geochemistry can be observed, which correlate with documented changes in tectonic setting. In this proposal, we aim to probe more deeply into these geochemical contrasts by using minerals such as zircon, apatite, and Fe-Ti oxides to provide constraints on the fugacities of oxygen, sulfur, and water. We will test the hypothesis that one of the main differences between magmas associated with these two different deposit types is their sulfur content, which in turn reflects different magmatic sources and melting conditions. A better understanding of the contrasting tectonic and magmatic settings conducive to the formation of porphyry and IOCG deposits will inform and constrain exploration for such deposits in less well studied regions such as the Canadian Cordillera.