Jixiangfeng Fm
Type Locality and Naming
It was named by the No. 2 Regional Survey Party under the Geological Bureau of Heilongjiang Province in 1980, and was first cited publicly by Wang Ying in 1985. The naming section is located on the northern slope of the Qishangfangzi Mts to the north of the Jixiangfeng Railway Station of Yakeshi City, Hulunbar League, Inner Mongolia. Lower (fourth) formation in Xing'anlin Gr.
Synonym: （吉祥峰组）
Lithology and Thickness
It represents a set of dark-colored soda-rich rhyolitic volcanic lava and volcaniclastic strata. The rock types of the formation are represented by basic rhyolite, rhyolitic porphyry, felsitic porphyry, quartz-porphyry, tuffaceous breccia, ignimbrite, volcanic tuff and a small amount of tuffaceous sandy conglomerate.
Relationships and Distribution
Lower contact
It is in a conformable contact with the underlying Tamulangou Fm
Upper contact
It is in a conformable contact with the overlying Murui Fm
Regional extent
The formation is distributed at the major peak of the Greater Khingan Mts as well as on the eastern and western slopes of the Greater Khingan. In the area of eastern slope and the major peak of the Greater Khingan the formation consists of an alternating layer of basic rhyolite, dacite, rhyolitic porphyry together with basic rhyolitic ignimbrite and pure ignimbrite, intercalated with a small amount of purple sandstone, with a thickness of 1955.8 m. On the western slope of the above-mentioned mountain the thickness of the formation is smaller. As is seen in the newly created Southwest Hill section on the Shangkuli Farm of the Ergune Right Banner the formation is composed mainly of tuffaceous breccia, ignimbrite and tuffaceous sandy conglomerate, with a thickness of over 100 m. The thickness of the formation on the eastern bank of the Ergune River of the Chenbarhu Banner is as great as 1076 m.
GeoJSON
Fossils
It yields plant fossils only in western part of the Chenbarhu Banner, as represented by Czekanowskia rigida, Pityophyllum sp., and Phoenicopsis.
Age
Depositional setting
Additional Information