Results
- Showing results for:
- Reset all filters
Search results
-
Journal articleDodd SC, Mac Niocaill C, Muxworthy AR, 2015,
Long duration (>4 Ma) and steady-state volcanic activity in the early Cretaceous Parana-Etendeka Large Igneous Province: New palaeomagnetic data from Namibia
, EARTH AND PLANETARY SCIENCE LETTERS, Vol: 414, Pages: 16-29, ISSN: 0012-821X- Author Web Link
- Cite
- Citations: 51
-
Journal articleDodd SC, Muxworthy AR, Mac Niocaill C, 2015,
Paleointensity determinations from the Etendeka province, Namibia, support a low-magnetic field strength leading up to the Cretaceous normal superchron
, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, Vol: 16, Pages: 785-797, ISSN: 1525-2027- Author Web Link
- Cite
- Citations: 7
-
Journal articleMuxworthy AR, Williams J, Heslop D, 2015,
Testing the use of viscous remanent magnetisation to date flood events
, Frontiers in Earth Science, Vol: 3Using erratics associated with large flood events, this paper assesses whether their viscous remanent magnetisation (VRM) can be used to date the flood events. We tested this method using flood erratics from three large events: (1) the Late Pleistocene Bonneville mega-flood in Idaho, USA, (~14–18 ka), (2) the 1918 A.D. Mt. Katla, Iceland, eruption and associated jökulhaup (meltwater flood) at Mýrdalssandur, and (3) the Markarfljót jökulhaup due to an earlier eruption of Mt. Katla (~2.5 ka). We measured 236 specimens, 66 of which yielded clear identifiable and measurable viscous magnetisation signals from erratics with clustered VRM directions. From the VRM unblocking temperatures, age estimates were made. The age estimate for the most recent event (Mýrdalssandur) worked well, with a median estimated age of 80 years (with individual erratic estimates distributed between 61–105 years) compared to the known age of 91 years. The ages of the other two events were over-estimated. The estimates for Markarfljót [15 ka (7–33 ka)] were based on the results of just one erratic. For the Bonneville flood the estimates were too old, however, this locality had the largest uncertainty in the ambient temperature used in the age determination; the VRM acquired is strongly dependent on the ambient temperature, the older the event the greater the uncertainty. Southern Idaho currently has hot summers, with average summer maximum temperatures of ~31°C, but a mean annual temperature of only ~ 9°C. It is suggested that the VRM dating method works best for recent events (<2–3 ka) where the ambient temperature history can be constrained.
-
Conference paperBerndt T, Muxworthy AR, 2015,
Temperature and grain size dependence of the attempt time \tau_{0} for fine magnetic particles (poster)
, Magnetic Interactions 2015 -
Conference paperSupakulopas R, Muxworthy AR, Døssing A, et al., 2015,
The magnetic properties and palaeodirections of basalts in Iceland: preparation to test the geocentric axial dipole hypothesis (GAD) (poster)
, Magnetic Interactions 2015 -
Conference paperBalikova D, Maidment S, Muxworthy AR, 2015,
The age of the Morrison Formation (Western Interior, USA): A Magnetostratigraphic Approach (poster)
, Magnetic Interactions 2015 -
Conference paperMuxworthy AR, Almeida T, Williams W, et al., 2015,
Observing remanence structures in sub- micron magnetite at high-temperatures
, Magnetic Interactions 2015 -
Conference paperShah J, Muxworthy AR, Genge M, 2015,
A micro-CT approach to the paleomagnetic conglomerate test
, Magnetic Interactions 2015 -
Conference paperValdez Grijalva M, Muxworthy AR, Williams W, 2015,
Micromagnetics of individual greigite SD and PSD grains
, Magnetic Interactions 2015 -
Conference paperDi Chiara A, Muxworthy AR, Trinidade R, 2015,
Palaeointensity of Proterozoic magmatic rocks from South America using the Preisach method, preliminary results
, Magnetic Interactions 2015 -
Journal articleBland PA, Collins GS, Davison TM, et al., 2014,
Pressure-temperature evolution of primordial solar system solids during impact-induced compaction
, Nature Communications, Vol: 5, Pages: 1-13, ISSN: 2041-1723Prior to becoming chondritic meteorites, primordial solids were a poorly consolidated mix of mm-scale igneous inclusions (chondrules) and high-porosity sub-μm dust (matrix). We used high-resolution numerical simulations to track the effect of impact-induced compaction on these materials. Here we show that impact velocities as low as 1.5 km s−1 were capable of heating the matrix to >1,000 K, with pressure–temperature varying by >10 GPa and >1,000 K over ~100 μm. Chondrules were unaffected, acting as heat-sinks: matrix temperature excursions were brief. As impact-induced compaction was a primary and ubiquitous process, our new understanding of its effects requires that key aspects of the chondrite record be re-evaluated: palaeomagnetism, petrography and variability in shock level across meteorite groups. Our data suggest a lithification mechanism for meteorites, and provide a ‘speed limit’ constraint on major compressive impacts that is inconsistent with recent models of solar system orbital architecture that require an early, rapid phase of main-belt collisional evolution.
-
Conference paperDøssing A, Muxworthy AR, Mac Niocaill C, et al., 2014,
High-Latitude Geomagnetic Secular Variation and Paleointensity during 6-0.5 Ma: Paleomagnetic Results from Eastern Iceland
, AGU Fall -
Conference paperAbubakar R, Muxworthy AR, Fraser A, et al., 2014,
Mapping Petroleum Migration Pathways Using Magnetics (poster)
, AGU Fall -
Conference paperDodd S, Mac Niocaill C, Muxworthy AR, 2014,
The Etendeka large igneous province, Namibia. A 4 Ma duration from detailed magnetostratigraphy (poster)
, AGU Fall -
Conference paperAlmeida TP, Kasama T, Muxworthy AR, et al., 2014,
Visualisation of chemical remanent magnetisation in pseudo-single domain Fe3O4 particles examined by environmental TEM and off-axis electron holography
, International Microscopy Congress
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.