Ísland myndaðist ekki þar sem möttulstrókurinn kviknaði fyrir 250 milljón árum
“Fyrir rúm 250 milljón árum kviknaði möttulstrókur lengst niðri í möttlinum. Á þessu tíma voru mörg lönd eins og Norður-Ameríka og evrópa/Asía eitt land sem var seinna nefnd Lárasía. Seinna fór þetta meginland að rifna í sundur og þá myndaðist Norður-Atlantshafið. Ísland myndaðist þar sem flekaskilin liggja og möttulstrókurinn er undir, þannig að kvika kemur stöðugt upp og myndar nýtt land.”
Summary
The breakup of the supercontinent Pangaeæ into Laurasia and Gondwana did occur about 250 million years ago, and the subsequent rifting created the North Atlantic. However, the Iceland mantle plume is only traceable to roughly 60 million years ago, not to the time of the Pangaeæ breakup, and Iceland itself emerged much later as a result of the Mid‑Atlantic Ridge and the plume, not as a continuous land‑building process dating back 250 million years.
Sources 60 searched
- iceland mantle plume: Topics by Science.gov
Although mantle plumes are widely implicated in models for the generation of large igneous provinces (LIPs) and the break-up of supercontinents such as Gondwana, the exact role of the mantle plume in these processes, and even the very existence of mantle plumes, is controversial and hotly debated.
- Global mantle isotopic anomalies linked to supercontinent-superocean evolution for the past 700 million years | Communications Earth & Environment
Earth’s mantle isotopic composition is highly heterogeneous, with enriched and depleted regions1–3 shaped by a complex history of depletion and re-enrichment over 4.5 billion years. The spatial configuration of large-scale heterogeneity in the mantle is not random4,5, but the timing and mechanisms that caused such heterogeneity are still debated2,6,7. We compiled radiogenic isotope data of mid-ocean ridge and plume-induced basalts from both present-day and past oceans for the past 900 million years of the relatively isotopically enriched African mantle domain.
- Tracing the Iceland plume and North East Atlantic breakup in the lithosphere | Communications Earth & Environment
Here we present an open access three-dimensional density model of the NEA crust and uppermost mantle that is consistent with previously un-integrated available data. We propose that high-density anomalies in the crust represent the preserved modifications of the lithosphere in consequence of the plate’s journey over the hot mantle plume.
- Mantle plumes, supercontinents, intracontinental rifting and mineral systems - ScienceDirect
The Phanerozoic Pangea supercontinent at 260 Ma had two main components, Laurasia in the north and Gondwana in the south, separated by the Palaeotethys Ocean. We focus on the rifting of Gondwana, which led to the formation of present day Atlantic and Indian oceans.
- The Iceland–Jan Mayen plume system and its impact on mantle dynamics in the North Atlantic region: Evidence from full-waveform inversion - ScienceDirect
We present a high-resolution S-velocity model of the North Atlantic region, revealing structural features in unprecedented detail down to a depth of 1…
- Continental crust beneath southeast Iceland - PMC - NIH
The Iceland hotspot is widely thought to be the surface expression of a deep mantle plume from the core–mantle boundary that can be traced back in time at least 62 My. However, some lavas contain continental material, which has previously been proposed to have been recycled through the plume.
- Breakup of Supercontinent Pangea Cooled Mantle and Thinned Crust | Jackson School of Geosciences | The University of Texas at Austin
The thinning is related to the cooling of Earth’s interior prompted by the splitting of the supercontinent Pangaea, which broke up into the continents that we have today, said Harm Van Avendonk, the lead author of the study and a senior research scientist at The University of Texas Institute for Geophysics. The findings, published in Nature Geosciences on Dec. 12, shed light on how plate tectonics has influenced the cooling of the Earth’s mantle throughout geologic history.
- Pangaea to the Present Lesson #2 | Volcano World | Oregon State University
Scientists believe these plates have been moving for millions of years. In fact, 250 millions years ago the Earth's seven continents were all grouped together into a supercontinent called Pangea.
- Laurasia - Wikipedia
A mantle plume (the Central Iapetus Magmatic Province) forced Laurentia and Baltica to separate ca. 650–600 Mya and the Iapetus Ocean opened between them. Laurentia then began to move quickly (20 cm/year (7.9 in/year)) north towards the Equator where it got stuck over a cold spot in the ...
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