干旱区生态环境知识资源中心(Arid): Sediment fill geometry and structural control of the Pampa del Tamarugal basin, northern Chile

Arid

DOI	10.1130/B31722.1
	Sediment fill geometry and structural control of the Pampa del Tamarugal basin, northern Chile
	Labbe, N.1,2; Garcia, M.1,2; Simicic, Y.1,2; Contreras-Reyes, E.3; Charrier, R.2,4; De Pascale, G.2; Arriagada, C.2
通讯作者	Labbe, N.
来源期刊	GEOLOGICAL SOCIETY OF AMERICA BULLETIN
ISSN	0016-7606
EISSN	1943-2674
出版年	2019
卷号	131 期号:1-2 页码:155-174
英文摘要	Determination of the sediment fill geometry and structure of basins along the western flank of the Central Andes is crucial for understanding the regional tectonic evolution and the geological situation of natural resources. In this study, we developed a sediment-thickness distribution model for the Pampa del Tamarugal basin (between 20 degrees 20'S and 21 degrees 30'S, northern Chile), from surface geological information, available wells, and interpretation and depth conversion of 14 seismic-reflection profiles. Four Oligocene-Holocene units and one Carboniferous-Eocene undifferentiated basement unit were identified in the seismic profiles. For depth conversion, we established an empirical velocity model using P-wave velocities measured from rock samples, with velocity values from 2 to 6 km/s. By interpolating the basal-fill surface from the processed data set, and subtracting it from the topographic surface, we generated an isopach map of the basin, which has a maximum fill thickness of 1566 m. Four N-S-elongated asymmetric subbasins with a fill exceeding 700 m in thickness were identified, and these are separated by four basement highs. Both basement and fill units are folded and cut by west-vergent high-angle reverse faults, which originated before the Oligocene and were reactivated in the Miocene. During the isopach map construction, three sources of error were identified (i.e., topographic adjustment, interpretation, and conversion method), and the mean accumulated thickness error was found to be +/- 250 m; in addition, the lack of wells as validation data also contributes to the uncertainty. Based on our results, the basin-fill geometry was controlled by both compressional tectonics, which generated uplifted blocks and accommodation spaces, and desertification, which has significantly decreased the sediment input since the late Miocene. Despite the uncertainties, our results provide new insights into Andean tectonics and may be used as a screening tool for natural resources such as minerals and groundwater.
类型	Article
语种	英语
国家	Chile
收录类别	SCI-E
WOS记录号	WOS:000454928000010
WOS关键词	FORE-ARC ; COASTAL CORDILLERA ; ATACAMA DESERT ; TECTONIC EVOLUTION ; GROUNDWATER-FLOW ; REGIONAL AQUIFER ; EXPOSURE AGES ; CENTRAL ANDES ; MAGMATIC ARC ; NEOGENE
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/2XILL650/215972
作者单位	1.Univ Chile, Adv Min Technol Ctr, Ave Tupper 2007, Santiago, Chile; 2.Univ Chile, Dept Geol, Fac Ciencias Fis & Matemat, Plaza Ercilla 803, Santiago, Chile; 3.Univ Chile, Dept Geofis, Fac Ciencias Fis & Matemat, Ave Blanco Encalada 2002, Santiago, Chile; 4.Univ Andres Bello, Escuela Ciencias Tierra, Santiago 2119, Chile
推荐引用方式 GB/T 7714	Labbe, N.,Garcia, M.,Simicic, Y.,et al. Sediment fill geometry and structural control of the Pampa del Tamarugal basin, northern Chile[J],2019,131(1-2):155-174.
APA	Labbe, N..,Garcia, M..,Simicic, Y..,Contreras-Reyes, E..,Charrier, R..,...&Arriagada, C..(2019).Sediment fill geometry and structural control of the Pampa del Tamarugal basin, northern Chile.GEOLOGICAL SOCIETY OF AMERICA BULLETIN,131(1-2),155-174.
MLA	Labbe, N.,et al."Sediment fill geometry and structural control of the Pampa del Tamarugal basin, northern Chile".GEOLOGICAL SOCIETY OF AMERICA BULLETIN 131.1-2(2019):155-174.