干旱区生态环境知识资源中心(Arid): Analysis of faulted fan surfaces and paleosols in the Palomares Fault Zone (Betic Cordillera, SE Spain): Paleoclimatic and paleoseismic implications

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DOI	10.1016/j.geomorph.2019.06.003
	Analysis of faulted fan surfaces and paleosols in the Palomares Fault Zone (Betic Cordillera, SE Spain): Paleoclimatic and paleoseismic implications
	Roquero, E.1; Silva, P. G.2; Rodriguez-Pascua, M. A.3; Bardaji, T.4; Elez, J.2; Carrasco-Garcia, P.5; Giner-Robles, J. L.6
通讯作者	Roquero, E.
来源期刊	GEOMORPHOLOGY
ISSN	0169-555X
EISSN	1872-695X
出版年	2019
卷号	342 页码:88-102
英文摘要	This study presents a multidisciplinary approach to the tectonic geomorphology and history of the Palomares strike-slip fault in the Eastern Betic Cordillera (SE Spain). Analysis combines geomorphological mapping of fan-surfaces, pedological studies of faulted sedimentary successions, geoelectrical prospection and typical paleoseismological routines of structural analyses. Combined application of these methods together with the existing geochronological databases offer probable paleoclimatic and paleoseismic scenarios for the zone from Middle Pleistocene to Holocene. This study segments the Palomares Fault (PLF) in three overlapping en echelon N-S trends (PLF1, PLF2, PLF3). The older PLF1 controls the main faulted Almenara-Almagro range fronts. The younger PLF2 cuts and beheads crusted fan surfaces in the Aljibejo zone (ABJ). The intermediate PLF3 controls the development of intervening tectonic reliefs and offset paleosol sequences in alluvial-colluvial deposits. Our analysis focuses on the PLF3 at the La Escarihuela site (ESCH), where outcrops display eight faulted paleosols developed on overlapped Middle Pleistocene colluvial-alluvial deposits, with variable vertical slip of between 21 and 12 cm (bulk accumulated offset: 33 cm), evidence of two surface faulting events. After the structural analysis of the fault planes (striae plunges) net left-lateral displacements of 120.9 +/- 3.3 cm (Event 1) to 69.1 +/- 5.2 cm (Event 2), associated with maximum magnitudes of c. 6.7-6.5 Mw. However, the faulted sequence is sealed by a thick mature calcrete horizon of similar characteristics to that faulted at the ABJ1 site. Regional chronological data on calcic soils and calcretes in SE Spain assign this mature calcrete to Oxygen isotopic stages (OIS) 9 (c. 300 ka). With this age fixed at the uppermost of the faulted paleosol sequence at the ESCH site (PLF3), soil development features (clay and carbonate contents, thickness, reddishness, etc.) were used as paleoclimatic proxies to correlate soil horizons with conventional OIS. Correlation indicates that clayey Bt soil horizons primarily occurred during warm isotopic stages followed by recalcification and carbonate accumulation (Btk; Bk; Ck horizons) during latter warmer stages. A proposed theoretical geochronological framework suggests that the sedimentary sequence at the ESCH site (PLF3) was deposited between OIS 18 and 9. Major environmental change towards the present semi-arid climate occurred during 01S 13 (c. 500 ka). During this same stage, paleoseismic event 1 also occurred, but paleoseismic event 2 took probably place during OIS 10 (c. 350 ka), before development of the uppermost calcrete sealing the deformation in this fault segment. However, this OIS 9 calcrete is faulted in the ABJ1 and a younger less developed calcrete is faulted in ABJ2 on the PLF2 segment. Chronology proposed in this paper suggests theoretical ages for these events of between OIS 8-01S 5 for ABJ1 (c. 200 ka) and between OIS 4-OIS 2 for ABJ2 (c 40 ka). This last paleoseismic event triggered major landscape changes with still-visible fault scarps, linear tectonic reliefs, alluvial fan beheading and active drainage shuttering. This present work illustrates the use of soil/paleosol analyses in paleoseismology as a useful tool to build paleoclimatic analogues and develop relative chronological frameworks from existing regional age data. (C) 2019 Elsevier B.V. All rights reserved.
英文关键词	Tectonic Geomorphology Paleosols Surface faulting Palomares Fault SE Spain
类型	Article
语种	英语
国家	Spain
收录类别	SCI-E
WOS记录号	WOS:000483417600007
WOS关键词	MURCIA FAULT ; CARBONERAS FAULT ; SOUTHEAST SPAIN ; EASTERN BETICS ; SHEAR ZONE ; QUATERNARY ; TECTONICS ; ALHAMA ; BASIN ; DEPOSITS
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS研究方向	Physical Geography ; Geology
来源机构	Arizona State University
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/216018
作者单位	1.Univ Politecn Madrid, Dept Edafol, ETSI Agronomos, Madrid, Spain; 2.Univ Salamanca, Escuela Politecn Super, Dept Geol, Avila, Spain; 3.IGME, Madrid, Spain; 4.Univ Alcala De Henares, UD Geol, Alcala De Henares, Madrid, Spain; 5.Univ Salamanca, Escuela Politecn Super, Dept Ingn Terreno, Avila, Spain; 6.Univ Autonoma Madrid, Dept Geol & Geoquim, Madrid, Spain
推荐引用方式 GB/T 7714	Roquero, E.,Silva, P. G.,Rodriguez-Pascua, M. A.,et al. Analysis of faulted fan surfaces and paleosols in the Palomares Fault Zone (Betic Cordillera, SE Spain): Paleoclimatic and paleoseismic implications[J]. Arizona State University,2019,342:88-102.
APA	Roquero, E..,Silva, P. G..,Rodriguez-Pascua, M. A..,Bardaji, T..,Elez, J..,...&Giner-Robles, J. L..(2019).Analysis of faulted fan surfaces and paleosols in the Palomares Fault Zone (Betic Cordillera, SE Spain): Paleoclimatic and paleoseismic implications.GEOMORPHOLOGY,342,88-102.
MLA	Roquero, E.,et al."Analysis of faulted fan surfaces and paleosols in the Palomares Fault Zone (Betic Cordillera, SE Spain): Paleoclimatic and paleoseismic implications".GEOMORPHOLOGY 342(2019):88-102.