Idiji Ridge

{{Short description|Mountain ridge in the country of Canada}} {{Infobox mountain | name = Idiji Ridge | image = | image_caption = | elevation_m = 2359 | elevation_ref = <ref name="KF">Elevation and coordinates derived from [[Google Earth]].</ref> | country=[[Canada]] | region_type = [[Provinces and territories of Canada|Province]] | region = [[British Columbia]] | district = [[Cassiar Land District]] | range = [[Tahltan Highland]] | map = Canada British Columbia | map_caption = Location in British Columbia | label_position = below | coordinates = {{coord|57|40|35.51|N|130|37|23.35|W|type:mountain_scale:100000|format=dms|display=inline,title}} | coordinates_ref= <ref name="KF"/> | topo_maker = [[National Topographic System|NTS]] | topo_map = {{Canada NTS Map Sheet|104|G|10}} }} '''Idiji Ridge''' is a [[mountain]] [[ridge]] extending east of [[Tencho Glacier]] on the southern flank of [[Mount Edziza]] in northwestern [[British Columbia]], Canada. It is bounded on the south by a valley containing an unnamed creek, on the east by [[Tennaya Creek]] valley and on the north by [[cirque]]s extending east of [[Ice Peak]].<ref name="Souther">{{cite map|last1=Souther|first1=J. G.|author-link1=Jack Souther|title=Geology, Mount Edziza Volcanic Complex, British Columbia|map=1623A|scale=1:50,000|type=[[Geological map]]|cartography=M. Sigouin, [[Geological Survey of Canada]]|publisher=[[Energy, Mines and Resources Canada]]|year=1988|language=en|doi=10.4095/133498|doi-access=free}}</ref> Idiji Ridge takes its name from the adjacent [[Idiji Glacier]]; ''Idiji'' means "it thunders" in the [[Tahltan language]].<ref name="Souther"/><ref>{{cite bcgnis|id=876|name=Idiji Glacier|access-date=2024-07-02}}</ref>

The highest point of Idiji Ridge reaches an elevation of {{convert|2359|m|ft|abbr=off}} at its westernmost end.<ref name="KF"/><ref name="Souther"/> Idiji Ridge is one of three ridges east of the [[Big Raven Plateau]] named by Canadian [[volcanologist]] [[Jack Souther]], the other two being [[Cartoona Ridge]] and [[Sorcery Ridge]] to the south.<ref name="Souther"/>

==Geology== The base of Idiji Ridge consists of [[sedimentary rock|sedimentary]], [[volcanic rock|volcanic]] and [[metamorphic rock|metamorphic]] rocks of [[Mesozoic]] and [[Paleozoic]] age. These rocks are overlain by [[Miocene]] [[alkali basalt]] flows of the [[Raspberry Formation]], the oldest [[geological formation]] of the [[Mount Edziza volcanic complex]]. The Raspberry rocks are overlain by [[Pliocene]] alkali basalt flows of the [[Tenchen Member]] of the [[Nido Formation]] which are overlain by [[Pleistocene]] [[comendite]], comenditic [[trachyte]] and [[pantellerite]] of the [[Pyramid Formation (British Columbia)|Pyramid Formation]].<ref name="Souther"/>

Overlying the Pyramid Formation is Pleistocene alkali basalt, [[hawaiite]] and minor [[tristanite]], [[trachybasalt]] and [[mugearite]] of the lower assemblage of the [[Ice Peak Formation]] which are in the form of lava flows and [[pyroclastic rock|pyroclastic]] [[breccia]]. The upper assemblage of the Ice Peak Formation is mainly present at the western end of Idiji Ridge. It consists of Pleistocene alkali basalt, trachybasalt, tristanite, mugearite, [[benmoreite]] and trachyte that are in the form of lava flows, [[lava dome]]s and pyroclastic breccia.<ref name="Souther"/>

The youngest rocks comprising Idiji Ridge are [[Holocene]] alkali basalts of the [[Big Raven Formation]] which occur at the westernmost end of the ridge. These alkali basalts are in the form of [[volcanic bomb]]s, [[Agglutinate (geology)|agglutinate]] and lava flows.<ref name="Souther"/>

==See also== *[[Volcanism of the Mount Edziza volcanic complex]]

==References== {{reflist}}

[[Category:Ridges of the Mount Edziza volcanic complex]] [[Category:Mesozoic British Columbia]] [[Category:Paleozoic British Columbia]] [[Category:Miocene British Columbia]] [[Category:Pliocene British Columbia]] [[Category:Pleistocene British Columbia]] [[Category:Holocene British Columbia]] [[Category:Tahltan place names]]