Cadomian magmatism is interpreted to indicate fragments of late Neoproterozoic-early Cambrian continental arcs bordering the northern margin of Gondwana. Cadomian rocks constitute the main elements of the continental crust of central Iranian block -including the Lut block-. An example of such Cadomian rocks from NE Iran is studied here: the Dehzaman igneous rocks within the Kashmar- Kerman Tectonic Zone -KKTZ-. The Cadomian exposure in NE Iran includes intrusive rocks with a thick sequence of felsic volcanic rocks. Zircon U-Pb dating of syenogranites and ryholites yielded 238U/206Pb crystallization ages of ≈521.3 to ≈524.3 Ma, respectively and the age of 557 Ma to Biosyenogranites already was obtained by Rossetti et al. -2015- -Ediacaran-Early Cambrian-. Geochemically, the intrusive rocks are mostly characterized by high-K content and are similar to the I-type granites. These rocks are characterized by enrichment in large ion lithophile elements -LILEs- and light rare earth elements -LREEs- along with depletion in high field strength elements -HFSEs-. Their initial εNd -t- ranges from -0.6 to -2.1 at 86Sr/87Sr -i-=0.7045-0.7073. The Cadomian rocks from NE Iran, along with similaraged rocks from Turkey and Iran are suggested to form in an early stage of an active continental margin.

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