Stratigraphy and structure of Cerro Jarau: new proposal

The Cerro do Jarau structure is located near the town of Quaraí, in the Rio Grande do Sul state, close to the international boundary with Uruguay. This circular feature has a diameter with approximately 8 km, presents some evidence of an origin by a meteoritic impact. It is located in the Paraná Basin and characterized by a central area with occurrence of sandstone surrounded by basalts of Serra Geral Formation. Previous works considered the structure as a dome-shaped feature. The objective of this paper is to present new data on the stratigraphy and structure of the Cerro Jarau, showing that the sandstones are structurally and stratigraphically overlying the basalts and both units exhibit centripetal dips. The structure of Cerro Jarau is therefore a basin-like feature and not a dome as admitted in previous studies.

Cerro do Jarau构造位于巴西里奥格兰德州（Rio Grande do Sul）的夸莱镇（Quaraí）附近，毗邻与乌拉圭的国际边界。该环形构造直径约8公里，存在陨石撞击成因的相关证据。其地处巴拉那盆地（Paraná Basin）内，特征为中心区域出露砂岩，外围被Serra Geral组（Serra Geral Formation）玄武岩环绕。既往研究曾将该构造认定为穹窿状构造。本文旨在公布关于Cerro Jarau构造地层与结构的新数据，结果表明砂岩在构造与地层序列上均覆于玄武岩之上，且两套岩层均表现出向心倾斜特征。因此，Cerro Jarau构造实为类盆地构造，而非既往研究所认定的穹窿构造。