Cenozoic stratigraphy and structure in the Central Andes

安第斯山脉中部是与南美/纳斯卡板块边界平行的新生代非碰撞造山带的组成部分，其特点是高海拔、高起伏对比和内排低起伏区。导致该造山带发育的构造过程可能开始于白垩纪-始新世，在玻利维亚前陆盆地层序中得到了很好的反映。这些沉积岩代表了一个独特的档案，提供了造山带和前陆盆地演化的几何形状、速率和历史的限制。虽然薄皮水平缩短被认为是该地区安第斯隆升的主要机制，但变形的时间和幅度以及前中生代中生界隆起对安第斯造山带的影响使得对安第斯前陆地区的构造演化进行明确的评价变得困难。这些不同的不确定性使以前关于安第斯山脉中南部晚新生代演化的模型受到质疑。在本项目中，我建议开展多学科研究，重点解决以下方面的不一致性：(1)安第斯山脉变形的幅度、时间和几何形状；(2)Alto de Izozog构造隆起的演化及其对前陆盆地演化的影响；(3)新生代沉积物预算估算和气候强迫参数，从而能够重建安第斯山脉的古地貌、古生态和构造演化。这些目标最好通过结合沉积学、地震地层学和地质年代学分析来实现，这些分析可对查科平原和班底山脉间带中厚达7.5公里的新生代地层进行分析。

The central Andes, an integral part of the Cenozoic non-collisional orogenic belt parallel to the South American/Nazca plate boundary, is characterized by high elevation, high relief contrasts, and internally drained areas of low relief. The tectonic processes that led to the development of this orogen, which may have commenced during Cretaceous-Eocene time are well reflected in the foreland basin sequence in Bolivia. These sedimentary rocks represent a unique archive providing constraints on the geometry, rates, and history of orogenic and foreland basin evolution. Although thin-skinned horizontal shortening has been proposed as the main mechanism responsible for the Andean uplift in this region, the timing and magnitude of deformation and the effect of the pre-Mesozoic Izozog High on the Andean orogen make an unambiguous assessment of the tectonic evolution of the Andean foreland region difficult. These various uncertainties bring to question previous models for the late Cenozoic evolution of the southern central Andes. I propose in this project a multidisciplinary study that focuses to resolve the inconsistencies in (1) magnitude, timing, and geometry of the Andean deformation, (2) evolution of the Alto de Izozog structural high and its impact on foreland basin evolution, (3) Cenozoic sediment budget estimates and climate forcing parameters, thereby permitting reconstruction of the paleogeomophologic, paleoecologic, and tectonic evolution of the Andes. These objectives are best achieved through combining sedimentological, seismic stratigraphical, and geochronological analyses of the up to 7.5-km-thick Cenozoic strata in the Inter- and Subandean zones and the Chaco plain.