干旱区生态环境知识资源中心(Arid): 80,000 years of geophysical stratigraphic record at the Serra da Capivara National Park, in northeastern Brazil: Uncovering hidden deposits and landforms at a canyon's floor

Arid

DOI	10.1016/j.jsames.2020.102691
	80,000 years of geophysical stratigraphic record at the Serra da Capivara National Park, in northeastern Brazil: Uncovering hidden deposits and landforms at a canyon's floor
	de Oliveira, Marcelo A. T.; Santos, Janaina C.; Lemos, Reginaldo
通讯作者	de Oliveira, MAT (corresponding author), Fed Univ Santa Catarina UFSC, Geosci Dept, Campus Florianopolis, BR-88048370 Florianopolis, SC, Brazil.
来源期刊	JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
ISSN	0895-9811
EISSN	1873-0647
出版年	2020
卷号	104
英文摘要	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.
英文关键词	Serra da capivara GPR Quaternary Stratigraphic archives River channel Pediments
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000600552900001
WOS关键词	QUATERNARY DEPOSITS ; SOUTHERN ; SEQUENCE ; AMERICA ; CLIMATE ; DESERT ; EVENT ; PIAUI ; STATE
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/349052
作者单位	[de Oliveira, Marcelo A. T.; Lemos, Reginaldo] Fed Univ Santa Catarina UFSC, Geosci Dept, Campus Florianopolis, BR-88048370 Florianopolis, SC, Brazil; [Santos, Janaina C.] Univ Fed Vale Sao Francisco UNIVASF, Campus Sao Raimundo Nonato, BR-64770000 Sao Raimundo Nonato, Piaui, Brazil
推荐引用方式 GB/T 7714	de Oliveira, Marcelo A. T.,Santos, Janaina C.,Lemos, Reginaldo. 80,000 years of geophysical stratigraphic record at the Serra da Capivara National Park, in northeastern Brazil: Uncovering hidden deposits and landforms at a canyon's floor[J],2020,104.
APA	de Oliveira, Marcelo A. T.,Santos, Janaina C.,&Lemos, Reginaldo.(2020).80,000 years of geophysical stratigraphic record at the Serra da Capivara National Park, in northeastern Brazil: Uncovering hidden deposits and landforms at a canyon's floor.JOURNAL OF SOUTH AMERICAN EARTH SCIENCES,104.
MLA	de Oliveira, Marcelo A. T.,et al."80,000 years of geophysical stratigraphic record at the Serra da Capivara National Park, in northeastern Brazil: Uncovering hidden deposits and landforms at a canyon's floor".JOURNAL OF SOUTH AMERICAN EARTH SCIENCES 104(2020).