{"id":471321,"date":"2026-09-15T12:33:57","date_gmt":"2026-09-15T19:33:57","guid":{"rendered":"https:\/\/climatescience.press\/?p=471321"},"modified":"2026-09-15T12:33:59","modified_gmt":"2026-09-15T19:33:59","slug":"scientists-resurrect-1960s-magnetic-data-to-reveal-how-continents-break-apart","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=471321","title":{"rendered":"Scientists Resurrect 1960s Magnetic Data to Reveal How Continents Break Apart"},"content":{"rendered":"\n
\"Infographic
AI generated by Grok<\/figcaption><\/figure>\n\n\n\n

Scientists, including Keele University\u2019s Emeritus Professor Peter Styles, have digitized and reanalyzed forgotten high- resolution aeromagnetic survey data from the late 1960s (around 1968\/69) over the Afar region of Ethiopia (and what is now Eritrea), integrating it with other \u201cvintage\u201d magnetic data from the Red Sea and Gulf of Aden.<\/strong><\/p>\n\n\n\n

The original survey, flown by Hunting Geology and Geophysics Ltd under the University of Newcastle upon Tyne in one of Earth\u2019s most inhospitable climates, produced data that was largely overlooked after the 1970s.<\/p>\n\n\n\n

The team (P.G. Purcell, R. De Ritis, and P. Styles) processed it with modern methods to create Total Magnetic Intensity and First Vertical Derivative maps.<\/p>\n\n\n\n

The Afar region is a classic site for studying the early stages of continental breakup (rifting), where the African, Arabian, and Somali plates meet in a triple junction near the East African Rift, Red Sea, and Gulf of Aden. As basaltic rocks form and cool during seafloor spreading, they record Earth\u2019s magnetic field polarity reversals as linear \u201cstripes\u201d (like barcodes or tree rings). A standard triple- junction model<\/strong> would predict a triangular pattern of these magnetic lineations radiating from the Afar Depression.<\/strong><\/p>\n\n\n\n

Instead, the reanalyzed data show magnetic anomalies trending roughly east-west in southern Afar (continuing the Gulf of Aden trend into the continent and nearly perpendicular to the younger NNE-trending Wonji Fault Belt of the Ethiopian Rift). North of the Tendaho- Goba\u2019Ad discontinuity, anomalies trend approximately NW\/SE (deviating ~30\u00b0 from the Red Sea axis). There are little or no clear signature matching expectations for simultaneous, equal-rate rifting along all three arms of the East African Rift.<\/p>\n\n\n\n

The researchers interpret the dominant magnetic signature as evidence of earlier (possibly Miocene) continental rifting as Africa and Arabia separated along a primary fracture following the Gulf of Aden- Red Sea path, later overprinted by younger magmatism and faulting. Cross- rift magnetic anomalies also appear in the East African Rift and Red Sea, though their origins remain unclear.<\/p>\n\n\n\n

Professor Styles noted: \u201cThese findings give a unique perspective on how our planet is constantly changing and shifting right beneath our feet. It\u2019s also a great example of the benefits of looking at all of the available data, even historical data, when testing new models and theories. Models come and go, but well- measured data lasts forever.\u201d<\/p>\n\n\n\n

The paper concludes that the 1968 Afar Survey data has been \u201cresurrected from an undeserved obscurity\u201d and can now contribute to studies of this complex region.<\/p>\n\n\n\n

This work highlights the value of revisiting historical geophysical datasets with modern tools to refine models of how continents stretch, thin, and eventually form new ocean basins, processes ongoing today in East Africa and the Red Sea region.<\/p>\n\n\n\n

\"Geological
The old data from the Afar region has been digitised and\u202fintegrated it with\u202fadditional\u202f\u201cvintage\u201d magnetic data from the Red Sea and Gulf of Aden regions.\u202f Credit: Keele University<\/figcaption><\/figure>\n\n\n\n

Miocene rifting mechanisms in the Afar- Red Sea- Gulf of Aden region (roughly 23- 5 Ma) <\/strong>represent a critical phase in the transition from continental extension to seafloor spreading as Arabia separated from Africa. This period followed the Oligocene impingement of the Afar mantle plume (~30- 31 Ma) and the associated Ethiopian-Yemen flood basalt province. It is highly relevant to the 1968 Afar magnetic survey reinterpretation, which suggests that the prominent east- west magnetic anomalies in southern Afar may record earlier Miocene magmatic rifting aligned with the Gulf of Aden trend (later overprinted by younger structures).<\/p>\n\n\n\n

Timing overview<\/strong><\/p>\n\n\n\n

Gulf of Aden:<\/strong> Rifting began in the early- mid Oligocene (~35- 30 Ma) in the east\/central parts; climax of continental rifting ~20- 18 Ma; seafloor spreading initiated ~21- 17 Ma in the east and propagated westward.<\/p>\n\n\n\n

Red Sea: <\/strong>Continental rifting initiated ~27- 23 Ma (late Oligocene- early Miocene) along much of its length, often linked to a major dike event ~24- 22 Ma. Significant Miocene extension occurred with limited early volcanism in places; seafloor spreading began later (~13 Ma or younger in the central\/southern parts).<\/p>\n\n\n\n

Afar and northern Main Ethiopian Rift (MER):<\/strong> Extension in Afar started ~29- 25 Ma shortly after the traps. A major reorganization occurred ~13- 8 Ma, with northward propagation of Afar rifting, rotation of the Danakil Block, and development of the triple junction configuration. The northern MER formed around ~11 Ma.<\/p>\n\n\n\n

Geological events were strongly diachronous across the region.<\/p>\n\n\n\n

Rifting mechanisms are debated and often involve a combination of processes rather than pure end-members. Common frameworks include:<\/p>\n\n\n\n

    \n
  1. Active vs. passive rifting<\/strong>\n