Journal de géologie et géophysique
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Paleomagnetism and AMS of Early Cretaceous Rocks from Mishbeh Ring Complex, South Eastern Desert, Egypt

Awad A, Mostafa R1, El-Hemaly I, Abd El-All E, Khashaba A and Abdeldayem A

Rock magnetic, paleomagnetic and magnetic fabric characteristics of the Mishbeh ring complex of Cretaceous age (Ca: 142 ± 15 Ma) have been investigated for establishing a new paleomagnetic pole for this Era. Rock magnetic measurements performed on these rocks reveal that both magnetite and titano-magnetite, with traces of hematite, are the principal magnetic carriers. Demagnetization processes reveal a single magnetic component of interpreted primary origin that reflects the age of this complex. The (ChRM) component isolated from Mishbeh ring complex has a mean direction of D/I=332°/22°, k=71.4, α₉₅=7.1, and N=94 specimens from six sites. This direction corresponds to a north paleomagnetic pole at Lat. 58°N and Long. 290°E, with K=70 and A₉₅=9.2. The consistency of resultant pole with the Cretaceous poles from Egypt and other parts of Africa implies the primary origin of this magnetization. Magnetic fabric measurements on these rocks indicate that most parts of the complex retain their primary fabric. These rocks are characterized by a weak foliated fabric with no signs of high degree of deformation.