This study focuses on an east-west trending belt of granitic to intermediate intrusions and their volcanic cover in the northern Dur Kan Complex, a continental slice outcropping to the north of the exposed Makran accretionary wedge in southeastern Iran. Field observations, petrographic descriptions, trace element, and isotope analyses combined with U-Pb zircon geochronology are presented to determine the time frame of magmatism and tectonic setting during the formation of these rocks. Results document three magmatic episodes with different melt sources for (1) granites, (2) a diorite-trondhjemite-plagiogranite sequence, and (3) diabases and lavas. Granites, dated at 170-175 Ma, represent crystallized melt with a strong continental isotopic contribution. The diorite-trondhjemite-plagiogranite sequence is 165-153 Ma old and derives from a mantle magma source with minor continental contribution. East-west trending diabase dikes and bodies intruded the granitoids, which were eroded and then covered by Valanginian (140-133 Ma) alkaline lavas and sediments. Alkaline dikes and lavas have a mantle isotopic composition. Temporal correlation with plutonites of the Sanandaj-Sirjan Zone to the northwest defines a narrow, NW-SE striking and nearly 2000 km long belt of Jurassic intrusions. The increasing mantle influence in the magma sources is explained by thinning of continental lithosphere and related mantle upwelling/decompression melting. Accordingly, the formation of the studied igneous rocks is related to the extension of the Iranian continental margin, which ultimately led to the formation of the Tethys-related North Makran Ophiolites.

A low‐grade metamorphic “Coloured Mélange” in North Makran (SE Iran) contains lenses and a large klippe of low temperature, lawsonite‐bearing blueschists formed during the Cretaceous closure of the Tethys Ocean. The largest blueschist outcrop is a >1,000 m thick coherent unit with metagabbros overlain by interlayered metabasalts and metavolcanoclastic rocks. Blueschist metamorphism is only incipient in coarse‐grained rocks, whereas finer grained, foliated samples show thorough metamorphic recrystallization. The low‐variance blueschist peak assemblage is glaucophane, lawsonite, titanite, jadeite±phengitic mica. Investigated phase diagram sections of three blueschists with different protoliths yield peak conditions of ~300–380°C at 9–14 kbar. Magnesio‐hornblende and rutile cores indicate early amphibolite facies metamorphism at >460°C and 2–4 kbar. Later conditions at slightly higher pressures of 6–9 kbar at 350–450°C are recorded by barroisite, omphacite and rutile assemblages before entering into the blueschist facies and finally following a retrograde path through the pumpellyite–actinolite facies across the lawsonite stability field. Assuming that metamorphic pressure is lithostatic pressure, the corresponding counterclockwise P–T path is explained by burial along a warm geothermal gradient (~15°C/km) in a young subduction system, followed by exhumation along a cold gradient (~8°C/km); a specific setting that allows preservation of fresh undecomposed lawsonite in glaucophane‐bearing rocks.

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