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U‐Pb analysis of zircons from igneous rocks in the Elashan Mountain, easternmost segment of the East Kunlun Orogen yielded 252–232 Ma. Geochemically, these rocks are mainly high in SiO2, K2O and K2O+Na2O contents, low in P2O5 and TiO2 contents, depleted in Ba, Sr, P, Ti and enriched in U, Hf, Zr, showing features of I‐type granite. The zircon εHf(t) values of the Early Triassic Jiamuge'er rhyolite porphyry (252±3 Ma) are positive (+1.6 to +12.1), suggesting a juvenile crustal source mixing with little old crustal component, and the zircon εHf(t) values of the Middle Triassic Manzhang'gang granodiorite (244±3 Ma) and Dehailong diorite (237+3 Ma) are predominately negative (−8.4 to +1.0), indicating an older crustal source. In comparison, the zircon εHf(t) values of the Late Triassic syenogranites from Suigen'ergang (234±2Ma), Ge'ermugang (233±2 Ma) and Yue'ergen (232±3 Ma) plutons vary from −3.8 to +5.0, suggesting a crust‐mantle mixing source. From Early–Middle Triassic (252–237 Ma) to Late Triassic (234–232 Ma), the geochemical characteristics of these rocks show the change from a subduction–collision setting to a post‐collision or within‐plate setting. By comparing of these new age data with 77 zircon U–Pb ages of igneous rocks of the eastern part of East Kunlun orogen from published literatures, we conclude that the igneous rocks of Elashan Mountain and these of the eastern part of East Kunlun Orogen belong to one magmatic belt. All these data indicate that the Triassic magmatic events of the eastern part of East Kunlun Orogen can be divided into three stages: 252–238 Ma, 238–226 Ma and 226–212 Ma. Statistically, the average εHf(t) values of the three‐stage igneous rocks show a tendency, from the old to young, from –0.75±0.25 to lower –2.65±0.52 and then to –1.22±0.25, respectively, which reveal the change of their sources. These characteristics can be explained as a crust‐mantle mixing source generated in a subductional stage, mainly crust source in a syn–collisional stage and a crust‐mantle mixing source (lower crust with mantle‐derived underplating magma) in a post‐collisional stage. The identification of these three magmatic events in the Elashan Mountain, including all the eastern part of East Kunlun Orogen, provides new evidence for better understanding of the tectonic evolution of the northward subduction and closure of the Paleo‐Tethyan (252–238 Ma), the collision of the Songpan–Ganzi block with the southern margin of Qaidam block (238–226 Ma), and the post‐collisional setting (226–212 Ma) during the Early Mesozoic period.

Amphibole phenocrysts, xenocrysts and cumulate xenoliths from Cenozoic volcanic rocks of the Bohemian Massif (BM) belong to the magnesio-hastingsite-pargasite-kaersutite series. Their host rocks are mostly basaltic lavas, stocks, dykes and breccia pipe fills, less commonly also felsic rocks. Felsic rocks with amphibole cumulate xenoliths represent differentiated magmas which have undergone polybaric fractionation of the mafic minerals. The calculated p-T conditions suggest that almost all amphiboles crystallized in a relatively narrow temperature range (1020-1100°C) at depths of~20-45 km (0.7-1.2 GPa) during the magma ascent. These p-T estimates are compatible with the published experimental data on the stability of kaersutite. We therefore suggest the presence of a deep magma chamber situated close to the crust-mantle boundary where amphibole xenoliths to megacrysts could have formed. Nevertheless, crystallization of rare amphibole rims during the magma ascent was observed in a hornblendite cumulate in sodalite syenite from "Giegelberg". The lowest concentration of incompatible elements in the amphiboles was found in xenocrysts in alkaline basaltic rocks and mantle xenoliths and megacrysts, followed by phenocrysts/xenocrysts in lamprophyric rocks, xenocrysts of cumulates in felsic rocks, and phenocrysts in subvolcanic rocks. Amphibole compositional and Sr-Nd isotope characteristics resemble those of amphiboles from metasomatic clinopyroxene/amphibole veins in mantle peridotites. The initial 143 Nd/ 144 Nd and 87 Sr/ 86 Sr ratios of amphiboles (0.51266-0.51281 and 0.70328-0.70407, respectively) are similar to those of their whole rocks (0.51266-0.51288 and 0.70341-0.70462, respectively). Amphiboles of the magnesio-hastingsite-pargasite-kaersutite series of the BM are mostly chemically homogeneous, with no pronounced Mg-Fe fractionation and zoning. The amphiboles are characterized by relatively homogeneous εNd (i) = +1.4 to +3.8 values: only a single sample from the České Středohoří Volcanic Complex (CSVC) yielded a negative εNd (i) (−0.6). This testifies to locally elevated proportions of recycled Variscan crustal material during melting of mantle peridotites rich in clinopyroxene-amphibole veins. These veins were formed by metasomatic fluids enriched in High Field Strength Elements (HFSE) and are isotopically similar to Enriched Mantle1 (EM1)-type mantle. Amphibole host rocks occur in areas with a significant concentration of basaltic magmas in rift zones along lithospheric block boundaries of the BM. Lithospheric mantle beneath such zones was probably strongly influenced by metasomatic fluids during the formation of clinopyroxene-amphibole veins in mantle peridotite that facilitated the generation of basaltic magma with amphibole.

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