Abstract Acquisition of high-resolution geophysical spatial data at the Serra Branca canyon, in the Serra da Capivara National park, in the semiarid of the Northeastern Brazil, enables depicting deposits and relict landforms that have never been reported before for the area. Ground Penetrating Radar (GPR) and GPS real-time kinematics (RTK) enable uncovering wide cut-and-fill structures, a relict perched river channel, relatively well-stratified alluvial deposits and two relict pediment surfaces that border the current canyon's thalweg. Optically Stimulated Luminescence (OSL) geochronology shows that the stratigraphic archive tends to fit important global climatic markers of the last glacial cycle. The relict river channel was active at least from marine isotopic stage (MIS) 5a to MIS 2, showing low sedimentation rates during about 60,000 years. Between the last glacial maximum (LGM) and the Holocene, the paleochannel was abandoned. The canyon's floor was incised, and the current thalweg was carved out, probably following a local baselevel drop. Well-structured alluvial deposits have accumulated near the outlet of the canyon since at least the Early Holocene. During the Middle Holocene, colluvial and alluvial deposits accumulated in sites near the cliffs that border the canyon. The study's geochronology coincides with the pace of independent paleoclimatic proxies from Northeastern Brazil, suggesting that a humid millennial drift was associated with the incision of local bedrocks and accumulation of alluvial and colluvial deposits during the Early and the Middle Holocene. Abandonment of the Pleistocene river channel, incision of the local baselevel, and creation of the canyon's current thalweg were probably caused by a Late Glacial humid spell that may coincide with Heinrich event 1 (H1), about 16,000 years ago. However, complementary geochronologic and sedimentologic data are crucial for improving knowledge about this major drainage system change at the study site.

中文翻译：

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巴西东北部塞拉达卡皮瓦拉国家公园 80,000 年的地球物理地层记录：揭示峡谷底部隐藏的沉积物和地貌

摘要 在巴西东北部半干旱地区的 Serra da Capivara 国家公园的 Serra Branca 峡谷采集高分辨率地球物理空间数据，能够描绘该地区以前从未报道过的沉积物和遗迹地貌。探地雷达 (GPR) 和 GPS 实时运动学 (RTK) 能够发现宽阔的挖填结构、残留的河道、分层相对较好的冲积沉积物和与当前峡谷的 thalweg 接壤的两个残留山墙表面。光激发光 (OSL) 地质年代学表明，地层档案往往符合上次冰期循环的重要全球气候标志。残存河道至少从海洋同位素阶段 (MIS) 5a 到 MIS 2 是活跃的，在大约 60,000 年期间显示出低沉积率。在末次冰期最大值 (LGM) 和全新世之间，古河道被遗弃。峡谷的底部被切开，目前的 thalweg 被雕刻出来，可能是在当地的基础水平下降之后。至少从全新世早期开始，在峡谷出口附近就已经积累了结构良好的冲积矿床。在中全新世期间，崩积物和冲积物堆积在与峡谷接壤的悬崖附近。该研究的地质年代学与来自巴西东北部的独立古气候代理的步伐一致，这表明潮湿的千年漂移与当地基岩的切割以及全新世早期和中期的冲积和崩积沉积物的积累有关。废弃更新世河道，切割当地基层，创造峡谷' 当前的 thalweg 可能是由大约 16,000 年前的海因里希事件 1 (H1) 发生的晚冰期潮湿期引起的。然而，互补的地质年代学和沉积学数据对于提高对研究地点这一主要排水系统变化的了解至关重要。