Mineralogical and geochemical features of the coarse saprolite developed on orthogneiss in the SW of Yaoundé, South Cameroon

Ndjigui, Paul‐Désiré; Badinane, M.F.B.; Nyeck, Brunot; Nandjip, H.P.K.; Paul, Bernard

doi:10.1016/j.jafrearsci.2012.11.008

Cited by 55 publications

(17 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The existence of a strong and positive correlation between Mn and REE (r = 0.71 to 0.98) may also indicate the effective role of Mn-oxides in concentration of REEs at Kanigorgeh. Mn-oxides also have good and positive correlations with Ni, Zn, Tl, and Pb (r = 0.84-0.94), which may reflect their significant role in fixation of these elements in the system (Ndjigui et al, 2013). The positive but weak correlations between Ti and all REEs (r = 0.21-0.32) may point to the fact that, despite the existence of noticeable quantities of TiO 2 in the form of rutile and anatase in the ores, these 2 Ti-bearing mineral phases did not play a drastic role in the concentration and distribution of REEs in the ores at Kanigorgeh.…”

Section: Mineral Controls On the Ree Distributionmentioning

confidence: 95%

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Abedini

Calagari²

2014

Turkish J Earth Sci

View full text Add to dashboard Cite

IntroductionBauxite deposits are formed by alteration and weathering of parent rocks rich in alumino-silicate minerals. These residual deposits are developed principally in tropical to subtropical climatic conditions with annual rainfall exceeding 1.2 m and an average temperature of >22 °C (Bardossy and Aleva, 1990;Mondillo et al., 2011). According to Bardossy and Combes (1999), these deposits are characterized into 3 major groups: lateritic bauxite deposits, karst bauxite deposits, and Tikhvin-type bauxite deposits. The first group is the product of in situ and direct chemical weathering of alumino-silicate rocks lying beneath the surface. The second group is developed on the surface of more or less karstified carbonates (limestone and dolomite) and scarce marls. The third group is formed on the surface of eroded alumino-silicate rocks and is the erosional product of lateritic bauxite deposits. Bardossy (1982), based upon parameters such as morphology and chemical compositions, classified the bauxite deposits into 6 distinct groups: Mediterranean type, Kazakhstan type, Timan type, Salento type, Tulsk type, and Ariege type. Based upon geographical situations, these deposits occurred in 7 belts throughout the world: the northern Mediterranean coast, Caribbean basin, Urals-Siberia-Central Asia, East Asia, Irano-Himalaya, Southwest Pacific, and North America.During the last few decades, geochemical investigations proved to have practical applications for determination of various aspects of formation and evolution of bauxite deposits such as the type of parent rocks; the roles of diagenetic, epigenetic, and supergene processes in connection to ore-forming mechanisms; physicochemical conditions of the environment of the ore formation (e.g., pH, Eh, intensity of draining, and climate); the mineral controls on distribution, mobilization, and fractionation of elements [particularly trace and rare earth elements (REEs)] in the course of bauxitization; and tectonometamorphic evolutions (Özlü,

show abstract

Section: Mineral Controls On the Ree Distributionmentioning

confidence: 95%

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Abedini

Calagari²

2014

Turkish J Earth Sci

View full text Add to dashboard Cite

show abstract

“…Laterite and lateritic soil constitute 33% of available mineral resources in tropical and subtropical zones of Africa, Australia, India, South-East Asia and South America. They are often found just below the surface of grasslands or forests [9,11,28]. In Cameroon, laterite and lateritic soil cover nearly 67% of the country surface [29,30].…”

Section: Introductionmentioning

confidence: 99%

Role of Heat-Treated Laterite on the Strengthening of Geopolymer Designed with Laterite as Solid Precursor

Poudeu¹,

Ekani²,

Djangang³

et al. 2019

ACSM

View full text Add to dashboard Cite

This paper aims to develop a low-cost, green construction material for low-income house builders. A series of geopolymer samples were prepared by partially substituting the Cameroonian lateritic soil (LS) with different quantities of heat-treated laterite (20~50 wt. %). The chemical composition of the LS was determined through inductively coupled plasma spectroscopy (ICP). The specimens were subjected to thermogravimetric and differential thermal analyses (TGA/DTA), X-ray diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). In addition, the compressive strength of dry and wet specimens was measured with a hydroelectric device. The results show that the geo-polymerization and properties like setting time and mechanical strength of the samples were improved through the combined action of the raw LS and the laterite treated at 500-600°C; the crystallized particles from non-clayed minerals and from aggregates of kaolinite also contribute to strength of the samples; crystalline phases formed a tridimensional skeleton in the microstructure of the geopolymer. The research provides a promising composite that can serve as a low-cost construction material with reduced environmental impact.

show abstract

“…The distinct horizons developed within it depend on short-or long-term alteration processes [5,6]. The generic model of the weathering mantle of the Yaounde geological formations belongs to the lateralization regime and is identical to whatever the lithology is [5,25,32]. It is composed of the base toward the top, of a ( ○ Alloterite or fine saprolite (1-2 m), consisting of goethite and hematite and with ghosts of original minerals; this horizon has, in places, small depressions or alveoli which are dry at the edge of the nodular horizon above or present a water circulation when they seem to mark the transition with the soft level; these cells are comparable to karst forms described by [33].…”

Section: Structure Of the Alteration Mantle (Shallow Aquifer)mentioning

confidence: 99%

Hydrogeological Characteristics of Shallow Hard Rock Aquifers in Yaounde (Cameroon, Central Africa)

Ngoupayou¹,

Bon²,

Mboudou³

et al. 2020

Groundwater Hydrology

View full text Add to dashboard Cite

The groundwater contained in the alterites is one of the main sources of water supply for many households in the city of Yaounde and its surroundings. Information from the field and laboratory studies was compiled and analyzed in order to understand the hydrogeological context of this superficial aquifer. Preliminary results show a staged morphology of the alteration mantle (regolith) of Yaounde migmatitic representative of the polyphase character of alteration processes observed in all granito-gneissic formations of the world. This mantle has a multilayer system whose soil sets could have a different hydrodynamic functioning. The values of the hydraulic conductivity have a normal distribution and vary over four orders of magnitude, attesting the variability of the hydraulic conductivity of the soft materials. The hydrometric and piezometric characteristics indicate that the aquifer has highly heterogeneous zones that would be related to the morphostructural character of the region. The δ 18 O mean values of the rain (−2.47‰) and shallow groundwater (−2.57‰) are not significantly different. They indicate that the recharge of the shallow aquifer of Yaounde Precambrian basement is recent and is done directly by infiltration of precipitation without any notable change due to evaporation. These programs relate to (a) "physical, hydrodynamic, and bacteriological characterizations of groundwater resources in the sedimentary and basement areas of Cameroon" and (b) "the impact of climate change and human activities on the water resources of Cameroon. " The activities carried out within the framework of these programs are more implemented in the alterites of the geological formations of the South Cameroon Plateau specifically those of the region of Yaounde and its surroundings [7][8][9][10][11][12]. In fact, because of the deficit service of the water distribution network, the groundwater of shallow unconfined aquifer constitutes, for many households in this region, one of the main sources of water supply.This chapter is a review of the main results obtained during the research carried out in the aquifers of the Pan-African basement of the Yaounde series in Central Africa. It is a synthesis of the results of the Theses [4,[13][14][15][16][17], DEA, DESS, and Master [11, 18, 19] studies focusing on the hydrogeological context of the upper part of the weathered and cracked basement of the Mfoundi watershed, which includes 11 sub-basins, Anga'a and Mingosso in Mefou (Figure 1). This compilation makes it possible to fill the gaps and/or to improve the knowledge of the aquifers of the weathered mantle in humid tropical zone, particularly in this part of South Cameroon facing the problems of drinking water supply.Groundwater Hydrology 12

show abstract

Mineralogical and geochemical features of the coarse saprolite developed on orthogneiss in the SW of Yaoundé, South Cameroon

Cited by 55 publications

References 52 publications

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Role of Heat-Treated Laterite on the Strengthening of Geopolymer Designed with Laterite as Solid Precursor

Hydrogeological Characteristics of Shallow Hard Rock Aquifers in Yaounde (Cameroon, Central Africa)

Contact Info

Product

Resources

About