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General Features of Magmatic Evolution Throughout the Earth’s History
Published in O.A. Bogatikov, R.F. Fursenko, G.V. Lazareva, E.A. Miloradovskaya, A. Ya, R.E. Sorkina, Magmatism and Geodynamics Terrestrial Magmatism Throughout the Earth’s History, 2020
O.A. Bogatikov, V.I. Kovalenko, E.V. Sharkov
The igneous assemblages of anorogenic regions (see Chapter 4) most closely resemble those of present-day continental intra-plate magmatism. They are usually formed under extensional conditions, followed by dome formation, the generation of rift structures, the development of large basaltic lava fields, etc. There appears to be a marked similarity between igneous assemblages in which rocks of the moderate-and high-alkaline series (mostly Ti-rich K–Na and, to a lesser extent, K), tend to predominate. The characteristic feature of Phanerozoic anorogenic magmatism is that, because these areas have been deeply eroded, the intrusive equivalents of the lava series tend to be widely exposed and in larger volumes. Moreover, these former rift environments sometimes contain predominantly intermediate and acid moderately alkaline rocks, which are not characteristic of the Cenozoic.
Volcanoes and Their Products
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Multiple flows in the same area can produce large lava fields, up to several square kilometers, next to volcanoes. Much larger, hundreds to thousands of square kilometer sized lava plateaus can form from a succession of eruptions, mostly from fissures instead of individual volcanic cones. Such eruptions produce flood basalts, often producing basalt flows that are many tens of meters thick and that travel hundreds of kilometers.
Lava fields as potential groundwater sources in Western Saudi Arabia
Published in M.M. Sherif, V.P. Singh, M. Al-Rashed, Hydrology and Water Resources, 2020
The largest lava fields in Saudi Arabia in terms of area and volume are the harrats of, Rahat, Khaybar, Ithnayn, Nawasif, Kishb and Kura. They have a cumulative area of about 58,000 km2 and a roughly approximated volume of 6,300 km3. There are other large harrats such as Shamah in the north and Hadn between Harrats Kishb and Nawasif but no detailed geologic maps were found for them.
Petrogenesis of the Hoy lava field, a long-lived continental mafic volcanic province in eastern Australia
Published in Australian Journal of Earth Sciences, 2023
T. J. Crossingham, T. Ubide, P. M. Vasconcelos, K. M. Knesel
Eastern Australia provides an ideal setting to investigate continental volcanism because it hosts a wide variety of eruptive systems, namely central volcanoes, lava fields and leucitites (Figure 1a; Wellman & McDougall, 1974). Central volcanoes are remnant shield volcanoes composed of both mafic and silicic rocks that young southward from ca 34 to 6 Ma (Wellman & McDougall, 1974). Leucitites are leucite-bearing basalts consisting of minor cones and flows that also young southward (Cohen et al., 2008; Johnson, 1989). The age-progressive central volcanoes and leucitites are interpreted to result from Australia’s migration over a mantle plume or plumes (Davies et al., 2015; Fishwick et al., 2008; Knesel et al., 2008; Sutherland, 2003; Vasconcelos et al., 2008; Wellman & McDougall, 1974; Zhang & O’Reilly, 1997). The lava fields, our focus, are generally small-scale volcanic fields dominated by mafic lava flows, cones and plugs. In contrast with the central volcanoes, lava fields do not show any simple age progression (Johnson, 1989; Wellman & McDougall, 1974). The potential origin of the lava fields includes: rift-related decompression melting (Cohen, 2007; Johnson, 1989); far-field stresses that induced decompression melting (Cas et al., 2017); edge-driven convection (e.g. Davies & Rawlinson, 2014; Demidjuk et al., 2007; Shea et al., 2022); heat flow from the warm Pacific mantle (known as the diffuse alkaline magmatic province model, DAMP model; Finn et al., 2005); mantle swells (Sutherland et al., 2012); and bursts in slab flux (Mather et al., 2020). The close spatial, temporal and compositional relationship between central volcanoes and lava fields provides key information about the underlying mechanisms that control the formation of such diverse volcanic types (e.g. Jones et al., 2020).