ABSTRACT
Twenty-one outcrops of igneous bodies were studied in a small area (ca. 335 sq. km) of folded sediments west of Anyim River in the
Lower Benue Rift. The extrusives occur mainly as basaltic to trachybasaltic tuffs and lapilli tuffs. The minor intrusives are found as basaltic
and dolerite sills composed essentially of plagioclase (An,,), augite, with or without olivine. The major intrusives are dioritic small
bodies considing of sodic plagioclase (An,,), biotite andor hornblende, and rarely nepheline. Common accessory minerals in these rocks
are magnetite, pyrite, apatite, sphene and quartz. Calcite appears to be secondpry, and biotite, in some cases, is a pseudomorph after
hornblende.
The rocks are mostlyalkalic, total alkali ranges from 3.21 to 9.92% with Na,0,2.62 to 6.55% and K,O
C., O (2021). Alkaline Intrusive and Extrusive Rock from Areas West of the Anyim River, South-Eastern Benue Though. Afribary. Retrieved from https://afribary.com/works/alkaline-intrusive-and-extrusive-rock-from-areas-west-of-the-anyim-river-south-eastern-benue-though
C., OBIORA "Alkaline Intrusive and Extrusive Rock from Areas West of the Anyim River, South-Eastern Benue Though" Afribary. Afribary, 12 May. 2021, https://afribary.com/works/alkaline-intrusive-and-extrusive-rock-from-areas-west-of-the-anyim-river-south-eastern-benue-though. Accessed 03 May. 2024.
C., OBIORA . "Alkaline Intrusive and Extrusive Rock from Areas West of the Anyim River, South-Eastern Benue Though". Afribary, Afribary, 12 May. 2021. Web. 03 May. 2024. < https://afribary.com/works/alkaline-intrusive-and-extrusive-rock-from-areas-west-of-the-anyim-river-south-eastern-benue-though >.
C., OBIORA . "Alkaline Intrusive and Extrusive Rock from Areas West of the Anyim River, South-Eastern Benue Though" Afribary (2021). Accessed May 03, 2024. https://afribary.com/works/alkaline-intrusive-and-extrusive-rock-from-areas-west-of-the-anyim-river-south-eastern-benue-though