caa a22 4500 44529972X CHVBK 20180317142553.0 cr unu---uuuuu 170323e20100901xx s 000 0 eng 10.1007/s11430-010-4044-6 doi (NATIONALLICENCE)springer-10.1007/s11430-010-4044-6 Characteristics and origin of mafic and ultramafic xenoliths in trachyandesite lavas from Heikongshan volcano, Tengchong, Yunnan Province, China [Elektronische Daten] [HongMei Yu, ChuanYong Lin, LanBin Shi, JianDong Xu, XiaoDe Chen] The trachyandesite lavas from Heikongshan volcano of the Tengchong volcanic cluster, Yunnan Province contain relatively abundant mafic and ultramafic small xenoliths comprising mainly gabbro, pyroxenite and rare lherzolites, all less than 2.5 cm in size. Gabbro xenoliths are characterized by "open” texture represented by relatively abundant vesicles and ground-mass fillings, while pyroxenite xenoliths are characterized by equigranular and poikilitic texture. Their mineral compositions (clinopyroxene ± orthopyroxene ± plagioclase) are similar to those of phenocrysts in lavas, and their equilibration temperature (1000-1125°C) is consistent with the crystallization temperature of the phenocrysts (998-1108°C). Thus, the textures and compositions of these xenoliths are different from those of lower crustal and mantle xenoliths, and were derived from the magma chamber. Among them, the gabbroic xenoliths come from the crystal-bubble-liquid zone at the top of the magma reservoir, while the pyroxenite xenoliths come from the cumulates in the bottom of magma reservoir. The studied single lherzolite xenolith with porphyroclastic texture has similar mineral compositions to the mantle xenoliths from eastern China, and is considered to be of upper mantle origin. It was brought into magma reservoir by replenishment magma, and might have experienced a cooling event before eruption. The formation of xenoliths in trachyandesite flows largely reflects the ascent, storage, evolution and eruption processes of magma. Science China Press and Springer-Verlag Berlin Heidelberg, 2010 magma chamber nationallicence xenoliths nationallicence geothermo-barometry nationallicence trachyandesite nationallicence Heikongshan volcano nationallicence Tengchong nationallicence Yu HongMei Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut Lin ChuanYong Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut Shi LanBin Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut Xu JianDong Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut Chen XiaoDe Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut Science China Earth Sciences SP Science China Press 53/9(2010-09-01), 1295-1306 1674-7313 53:9<1295 2010 53 11430 https://doi.org/10.1007/s11430-010-4044-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11430-010-4044-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yu HongMei Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut NATIONALLICENCE 700 1- Lin ChuanYong Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut NATIONALLICENCE 700 1- Shi LanBin Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut NATIONALLICENCE 700 1- Xu JianDong Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut NATIONALLICENCE 700 1- Chen XiaoDe Institute of Geology, China Earthquake Administration, 100029, Beijing, China aut NATIONALLICENCE 773 0- Science China Earth Sciences SP Science China Press 53/9(2010-09-01), 1295-1306 1674-7313 53:9<1295 2010 53 11430 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer