Abstract The Andean basin formation across the Altiplano-Puna plateau has been mostly associated with: (i) interconnected depozones within a simple eastward-migrating foreland, (ii) isolated depocenters in a broken foreland or (iii) intermontane basins within a rising plateau setting. Particularly, the regions located further east from the western orogenic belts are key to disentangle these proposals. The Pozuelos Basin is today an internally-drained depositional area located at ∼22°22′S in the easternmost Andean plateau (an area known as the Puna). While this basin might be key to understanding the formation of basins at these latitudes, between belts Puna and Cordillera Oriental, during the Andean orogeny, only a few studies have been done since most of their records are in subsurface. In order to address the Cenozoic formation and evolution of the Pozuelos Basin, and support some of the Andean basin formation hypotheses, we conducted seismic data interpretation, complemented with field surveys. Data allowed the correlation of seismic reflectors, five identified tectono-sequences (two basements –non-stratified and stratified– packages and three stratified Cenozoic packages) and subsurface structures with the local outcropping geology. In contrast to other areas from the Puna and Altiplano, the Pozuelos basin seems to have been affected by basement thrusting and deformation along its eastern boundary, previous to the late Miocene plateau formation. Despite that in the basin configuration was clearly an isolated and intermontane setting since the late Miocene, seismic and stratigraphic data suggest that during the Late Oligocene - Middle Miocene the Pozuelos basin would have behaved as well as a disconnected depositional zone. Some features like sequence encroachments and stratigraphic arrangements in outcrops drove us to interpret an intermontane broken foreland.

中文翻译：

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阿根廷安第斯高原 Pozuelos 盆地地震解释与新生代构造演化

摘要 横跨 Altiplano-Puna 高原的安第斯盆地形成主要与：(i) 简单的向东迁移前陆内相互连接的沉积带，(ii) 破碎前陆中的孤立沉积中心或 (iii) 上升高原环境中的山间盆地. 特别是，位于西部造山带以东的地区是解开这些建议的关键。Pozuelos 盆地如今是位于安第斯高原最东端约 22°22'S 的内排水沉积区（称为普纳区）。虽然这个盆地可能是了解这些纬度盆地形成的关键，在安第斯造山运动期间，位于普纳带和东科迪勒拉带之间，但由于大部分记录都在地下，因此只进行了少数研究。为了解决 Pozuelos 盆地的新生代地层和演化问题，并支持安第斯盆地的一些地层假设，我们进行了地震资料解释，并辅以实地调查。数据允许将地震反射层、五个已识别的构造序列（两个基底 - 非分层和分层 - 包和三个分层的新生代包）和地下结构与当地露头地质相关联。与 Puna 和 Altiplano 的其他地区相比，Pozuelos 盆地似乎在晚中新世高原形成之前受到了沿其东部边界的基底逆冲和变形的影响。尽管自中新世晚期以来盆地构造显然是一个孤立的山间环境，地震和地层数据表明，在渐新世晚期 - 中中新世期间，Pozuelos 盆地的行为与不连续的沉积区一样。一些特征，如层序侵占和露头的地层排列，促使我们解释山间破碎的前陆。