Mineralogical and geochemical properties of clay deposits in parts of Southeastern Nigeria

Abstract

The rocks underlying many parts of Southeastern Nigeria had undergone extensive alterations to form considerable clay deposits. The mineralogical compositions of some of these clay deposits were evaluated with the X-Ray Diffraction (XRD) method to ascertain the suitability of the deposits as raw materials. Results of the analyses indicated that kaolinite (Al 2 Si 2 O 5 (OH) 4 ) is the dominant clay mineral. Traces of bentonite and dickite were also observed, while the identified non-clay minerals were quartz and iron. Chemical analysis of the clays revealed the predominance of SiO 2 , Al 2 O 3 , Fe 2 O 3 and TiO with values ranging from 31.70 to 56.45%, 19.30 to 29.30%, 3.11 to 29.42% and 2.21 to 7.04%, respectively, while the compositions of CaO, MgO, Na 2 O, and MnO in the analyzed samples were relatively lower with values ranging from 0.19 to 0.29%, 0.13 to 0.19%, 0.11 to 0.70% and 0.01 to 0.03%, respectively. The Al 2 O 3 /TiO 2 ratio (3.7 to 13.5) of the studied clays indicated a mafic to intermediate igneous rock origin. Binary plots of TiO 2 versus Al 2 O 3 to distinguish between granitic and basaltic sourced clays indicated basalt-rhyolite/granite provenances. The high chemical index of alteration (95.8%), chemical index of weathering (98.3%) and low contents of alkali and alkali earth elements (averaging 0.11%) of the clayrich sediments, is indicative of a relatively intense weathering source area. The SiO 2 -K 2 O/Na 2 O plots suggested that the sediments in the study area were deposited between passive and active continental margins. In comparison with other reference clays and standard specifications, the clay deposits in the study area possess characteristics satisfactory for economic and some engineering purposes.

Commercially Imported Bentonite Versus Locally Derived Bentonitic Clays: A Comparative Assessment Study of Mineralogy and Geochemical properties, Anambra Basin, Southeastern Nigeria

“…Also, the chemical index of alteration (CIA) proposed by Nesbitt and Young [34], was calculated for the studied samples to establish the extent of alteration/weathering. The CIA varied from (75-97%), this indicates reduction in the contents of alkali and alkaline earth elements (Table 2), as recorded from the studied clays, typically suggesting a relatively intense weathered source area [7]. The significant presence of kaolinite in the investigated clays could undoubtedly lead to poor rheological properties since such type of clay has low swelling capability.…”

“…Meanwhile, several clay deposits have been discovered, their industrial uses investigated and reported in Nigeria [1][2][3][4][5][6][7] These deposits range from lateritic/residual clays from weathered products of basement complexes [3,4,7] to those arising from sedimentary units within the various sedimentary basins, as well as those formed along major river channels [1,5,6]. A survey carried out by the Nigerian Mining Corporation typically established the presence of bentonitic clay reserves of over 700 million tonnes within Nigeria, with the largest deposit found in Afuze, Edo State, estimated at 70-80 million tonnes [8].…”

Application of Scheffe’s Model for stabilization of Amuro-okigwe subgrade using male inflorescence of oil palm ash

“…The study area, which lies within the geographical coordinates [4]. The average annual rainfall is about 2400mm and there is a distinct dry season of about 3-month dryness.…”

“…Pavement failure issues include cracking, potholes, depressions, rutting, shoving, upheavals, and raveling [1]. Source: Mineralogical and geochemical properties of clay deposits in parts of Southeastern Nigeria, [4] Sometimes, the defective pavement and unstable surfacing materials are removed down to a stable base before overlaying with new materials. Sooner than later these remedial works are done, pot holes and rutting usually resurface.…”

A Synoptic Review of Mineralogical and Chemical Characteristics of Clays in the Southern Part of Nigeria

“…However, they recommended that the Cretaceous Lakiri kaolins can be used in the paper and ceramic industry (except for kaolins having high TiO 2 and K 2 O content). [32] used XRD to evaluate the suitability of clay mineral as raw material in Ikpankwu, Okigwe down to Ohiya in the Okigwe-Umuahia axis. Results from the study showed that the clays are mainly kaolins; with traces of bentonite and dickite, non clay mineral content included quartz and iron.…”