Paleomagnetism and 40Ar/39Ar Geochronology of Yemeni Oligocene volcanics: Implications for timing and duration of Afro-Arabian traps and geometry of the Oligocene paleomagnetic field

Riisager, Peter; Knight, Kim B.; Baker, Joel A.; Ukstins, Ingrid; Al-Kadasi, Mohamed; Al-Subbary, Abdulkarim; Renne, Paul R.

doi:10.1016/j.epsl.2005.06.016

Cited by 40 publications

(38 citation statements)

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“…The lava flows were erupted into two stages (Chiesa et al 1983): early basaltic traps (>2 km thick) were produced between 31 and 26 Ma (Civetta et al 1978;Chiesa et al 1989;Baker et al 1996) while the second stage is comprised of acidic rocks dated between 23 and 18 Ma (Civetta et al 1978;Mohr 1991;Zumbo et al 1995). Riisager et al (2005) has further refined these ages on the basis of Ar-Ar geochronology and magnetostratigraphy, evidencing a first and short phase of basaltic volcanism between 30.3 and 26. volcanics also occurs in different parts of Yemen . The Quaternary volcanics are characterized by a basaltic activity with formation of volcanic cones (Chazot et al 1998).…”

Section: Geological Setting Of Yemenmentioning

confidence: 98%

Paleostress analysis of the volcanic margins of Yemen

Khanbari

Huchon

2010

Arab J Geosci

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The western part of Yemen is largely covered by Tertiary volcanics and is bounded by volcanic margins to the west (Red Sea) and the south (Gulf of Aden). The Oligo-Miocene evolution of Yemen results from the interaction between the emplacement of the Afar plume, the opening of the Red Sea, and the westward propagation of the Gulf of Aden. Structural and microtectonic analyses of fault slip data collected in the field reveal that the volcanic margins of Yemen are affected by three main extensional tectonic events. The chronological order of these events is as follows: first E-W extension was associated with the emplacement of volcanic traps of Yemen, then NE-SW extension was related to the Red Sea rifting, and finally, the volcanic margin was submitted to N160°E extension, perpendicular to the overall trend of the Gulf of Aden, which we interpret as induced by the westward propagation of the oceanic ridge of the Gulf of Aden.

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Section: Geological Setting Of Yemenmentioning

confidence: 98%

Paleostress analysis of the volcanic margins of Yemen

Khanbari

Huchon

2010

Arab J Geosci

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“…Magmatism intrudes Precambrian basement through vent systems known as harrats. Radiometric age determinations from 317 localities suggest that there are two separate magmatic phases with evidence of younging from south to north (Figure ) [ Civetta et al ., ; Coleman et al ., ; Pallister , ; Capaldi et al ., ; Chisea et al ., ; Hussain and Bakor , ; Camp and Roobol , ; Brown et al ., ; Sebai et al ., ; du Bray et al ., ; Baker et al ., ; Coulié et al ., ; Riisager et al ., ; Krienitz et al ., ; Trifonov et al ., ; Al‐Kwatil et al ., ; Moufti et al ., ]. An older (30–20 Ma) series is contemporaneous with Ethiopian flood basalts and is predominantly tholeiitic to transitional in composition [ Camp and Roobol , ].…”

Section: Geologic and Geophysical Evidencementioning

confidence: 99%

“…(b) Paleo‐elevation map at > 34 Ma; solid lines = modeled river profiles. (c) Topographic map centered on Yemeni basaltic province; red line delimits basalt outcrop; colored circles = 40 Ar/ 39 Ar ages [ Baker et al ., ; Riisager et al ., ]. (d–l) Inverse modeling of profiles.…”

Section: Calculating Uplift Historiesmentioning

confidence: 99%

“…(d–f) Wadi Shiam. Top; color bar and dashed lines = independent uplift estimates; M = marine fauna of Twailah Group [ Al‐Subbary et al ., ]; B = eruption of basalts [ Baker et al ., ; Riisager et al ., ]; G = granitic intrusions [ Menzies et al ., ]; E = erosion of basaltic flows [ Menzies et al ., ]. Solid line and gray band = uplift rate history with one σ uncertainty from varying erosional parameters that yields best fit between observed and calculated profiles; blue polygon = average uplift rate from elevation of Eocene marine sedimentary rocks; green polygon = average uplift rate determined from denudation rates [ Menzies et al ., ].…”

Section: Calculating Uplift Historiesmentioning

confidence: 99%

“…These estimates are corroborated by thermochronometric analyses which show that rapid cooling and exhumation commenced at 20–25 Ma [ Menzies et al ., ]. Eruption and later erosion of basaltic lava flows coincide with the onset and peak of calculated uplift [ Baker et al ., ; Riisager et al ., ]. Thus geologically meaningful uplift rate histories of regions, separated by ∼ 2000 km, are obtained using a single trade‐off relationship between v and m .…”

Section: Calculating Uplift Historiesmentioning

confidence: 99%

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Cenozoic epeirogeny of the Arabian Peninsula from drainage modeling

Wilson

Hoggard

White

2014

Geochem. Geophys. Geosyst.

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It is generally accepted that the Arabian Peninsula has been uplifted by subcrustal processes.Positive residual depth anomalies from oceanic crust in the Red Sea and in the Gulf of Aden suggest that a region surrounding this peninsula is dynamically supported. Admittance calculations, surface wave tomography studies, and receiver function analyses all imply that regional topography is generated and maintained by some combination of mantle convective circulation and lithospheric thickness changes. Despite these significant advances, the spatial and temporal uplift rate history of the Arabian Peninsula is not well known. Here we show that a regional uplift rate history can be obtained by jointly inverting 225 longitudinal river profiles that drain this peninsula. Our strategy assumes that shapes of individual river profiles are controlled by uplift rate history and moderated by erosional processes. We used local measurements of incision rate to calibrate the relevant erosional parameters. In our inverse algorithm, uplift rate is permitted to vary smoothly as a function of space and time but upstream drainage area remains invariant. We also assume that knickzone migration is not lithologically controlled. Implications of these important assumptions have been investigated. Our results suggest that the Arabian Peninsula underwent two phases of asymmetric uplift during the last 20-30 Ma at rates of 0.05-0.1 mm a 21 . The southwestern flank of the peninsula has been uplifted by 1.5-2.5 km. Regional stratigraphic constraints, the age and composition of volcanism, paleosol formation, incised peneplains, emergent marine terraces, and thermochronometric measurements corroborate our calculated patterns of uplift. Progressive development of three domal swells along the western margin of the peninsula is consistent with localized upwelling of hot asthenospheric mantle.

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More stable yet bimodal geodynamo during the Cretaceous superchron?

Lhuillier

Gilder

Wack

et al. 2016

Geophysical Research Letters

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We report palaeomagnetic and 40Ar/39Ar dating results from two sequences of basaltic lava flows deposited at the same locality in western China, yet separated in time by ~50 Myr: one set lies within the Cretaceous normal superchron at 112–115 Ma and a second at 59–70 Ma spanning the Cretaceous‐Palaeogene boundary. We find that magnetic field directions during the superchron exhibit bimodal populations: one with inclinations representative of a dipolar field and another with shallow inclinations that could reflect a more complex, multipolar field. However, the time‐dependent variability in field directions was 50% lower during the superchron than after, which implies greater field stability during the superchron. Our results suggest that episodes of less dipolar field behavior occurred within the Cretaceous superchron and raise the question whether a second, more multipolar, field state is more persistent than previously thought.

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Paleomagnetism and 40Ar/39Ar Geochronology of Yemeni Oligocene volcanics: Implications for timing and duration of Afro-Arabian traps and geometry of the Oligocene paleomagnetic field

Cited by 40 publications

References 61 publications

Paleostress analysis of the volcanic margins of Yemen

Paleostress analysis of the volcanic margins of Yemen

Cenozoic epeirogeny of the Arabian Peninsula from drainage modeling

More stable yet bimodal geodynamo during the Cretaceous superchron?

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