Subsidence in the Midst of Plateau Uplift: Neogene Evaporitic Basins of Northwest Argentina

在岩浆弧内形成的沉积盆地， 对高原的了解很少。 基本问题包括： 有没有地壳沉降或者沉积物的沉淀 这种构造沉降是由于岩浆运动、地壳运动造成的吗？ 减薄、推力加载或原有密度的再活化 异常现象 观察和理论处理， 盆地是罕见的，尽管广泛的研究的成因， 沉积盆地中。 约旦将研究新第三纪和第四纪内- 中安第斯山脉的弧形/高原内盆地， 阿根廷西北部的普纳高原。 晚中新世至 最近的沉积中心积累了2000至5000米的地层， 整个地区都在上升。 潜在的原因线索 包括它们与重力高的重合， 它们缺乏沉积物的事实。 蒸发岩相是 体积上重要、寿命长、经济上重要。 这项工作将记录盆地的古地理 从中新世到近代 相、接触研究 盆地充填物与邻近基岩、物源 和古水流的绝对年代测定 插灰

Sedimentary basins that form within magmatic arcs and plateaus are poorly understood. Basic questions include: Has there been any tectonic subsidence or just ponding of sediment? Is such tectonic subsidence due to magmatic movement, crustal thinning, thrust loading, or reactivation of pre-existing density anomalies? Observations and theoretical treatments of such basins are rare, in spite of extensive study of the genesis of sedimentary basins in other settings. Jordan will study Neogene and Quaternary intra- arc/intraplateau basins of the Central Andes mountain chain, in the Puna plateau of northwestern Argentina. Late Miocene to Recent depocenters accumulated 2000 to 5000 m of strata while the whole region was being uplifted. Potential clues to the causes of the basins include their coincidence with gravity highs and the fact that they are sediment-starved. Evaporite facies are volumetrically important, long-lived, and economically important. The work will document the paleogeography of the basins through the Miocene to Recent. Study of facies, contact relations between the basin fill and adjacent bedrock, provenance and paleocurrents will be complemented by absolute dating of intercalated ashes.