DOI: 10.1016/j.earscirev.2021.103619
论文题名: Volcanic history of the Derceto large igneous province, Astkhik Planum, Venus
作者: MacLellan L. ; Ernst R. ; El Bilali H. ; Ghail R. ; Bethell E.
刊名: Earth Science Reviews
ISSN: 00128252
出版年: 2021
卷: 220 语种: 英语
中文关键词: (max. 5–7). Venus
; Derceto Corona
; Flood basalt
; Kallistos Vallis
; Planetary geology
; Ubastet Fluctus
英文关键词: dike
; dike swarm
; erosion rate
; flood basalt
; image resolution
; large igneous province
; mafic rock
; pixel
; planetary landform
; sill
; structural geology
; Venus
; volcanology
英文摘要: Detailed mapping of major-scale volcanic centres on Venus provides a complementary view to terrestrial large igneous provinces (LIPs). On Venus, the surface flood basalt relationships are preserved owing to the absence of erosion, but the plumbing system is only indirectly revealed. In contrast, erosion on Earth dissects flood basalt packages and can directly reveal the plumbing system of mafic dykes, sills and larger intrusions. Herein we report on detailed mapping at 1:500,000 scale of the Derceto Corona (DC) volcanic event located in southern Astkhik Planum (our map area: 1,920,000 km2) using full resolution (100–200 m/pixel) Magellan synthetic aperture radar (SAR images). Our map builds on earlier reconnaissance scale mapping (1:5,000,000 scale) in parts of quadrangles V-44, V-45, and V-56. Thirty-seven distinct lava flow units were mapped and grouped into eight main and multiple minor volcanic stages, along with six regional graben systems (marking underlying dyke swarms). On the east side of DC, the Eastern Stage flows (fES) which extend for 750 km, are fed from NNW-NW-trending grabens (overlying dykes) and from more local (small shield) sources. The Kallistos-Ubastet Stage (fKUS) consists of the 1200 km long Kallistos Vallis and its overflow Ubastet Fluctus, all fed from an irregular 30 × 10 km depression (interpreted to represent roof collapse above a magma chamber) on the south side of DC. Lavas of both the Eastern Stage and the Kallistos-Ubastet Stage flowed over a section of Vaidilute Rupes and spread out on its eastern side. A Western Stage flow field (fWS-3) (>1000 km long) was sourced from the elliptical graben system (overlying dykes) of DC; after flowing downslope to the north it swings almost 180 degrees to follow a preexisting rift, Hanghepiwi Chasma. At its distal end, fWS-3 is locally superimposed with radar-bright flows interpreted to be derived from east-trending grabens (overlying dykes) belonging to Sarpanitum Corona. On the north side of DC, a laterally propagating NE-trending graben system (overlying dykes) produces a 90 km long “Great Dyke” that itself feeds a flow field; additional grabens of this swarm also spawned smaller flows. All the above-mentioned flows have sources within 250 km from the centre of DC, within the area of interpreted original regional uplift, and possible magmatic underplate. Two flow stages (Western Stage-3 and the Great Dyke/NE-trending dyke swarms) are inferred to be fed via dykes from elliptical-shaped down-sag caldera collapse of DC. The Eastern Stage flows are fed mostly from a region to the east of the corona, and the rest of the flows are fed via an older (pre-Derceto) regional NW-trending graben system that was reused for magma transport from underlying chambers fed from the magmatic underplate or laterally from the collapse of the central chamber of DC. The total areal extent of flows is 534,650 km2 with an inferred volume of 26,730 km3 (assuming a flow thickness of 50 m), corresponding to LIP-scale in terms of area, and likely LIP-scale volume if the expected underlying plumbing system were catalogued. © 2021 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/166461
Appears in Collections: 气候变化与战略
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作者单位: Department of Earth Sciences, Carleton University, Ottawa, K1S 5B6, Canada; Faculty of Geology and Geography, Tomsk State University, Tomsk, 634050, Russian Federation; Department of Earth Sciences, Royal Holloway University of London, Egham, TW20 0EX, United Kingdom
Recommended Citation:
MacLellan L.,Ernst R.,El Bilali H.,et al. Volcanic history of the Derceto large igneous province, Astkhik Planum, Venus[J]. Earth Science Reviews,2021-01-01,220