iron ore deposits in agbaja area by professor olatinpo o.a

1 OLUSEGUN A. OLATINPO (2015)

A PART OF RESEARCH CARRIED OUT BY

OLATINPO, OLUSEGUN AYOBAMI

14/68ET003

AT THE UNIVERSITY OF ILORIN, ILORIN

ON SOME SELECTED MINERAL DEPOSITS IN NIGERIAN

SEDIMENTARY BASIN

IRON ORE DEPOSIT IN AGBAJA FORMATION,

SOUTHERN BIDA BASIN, NIGERIA

ADVANCED SEDIMENTOLOGY COURSE (GEM 690)


OUTLINE

1.0 INTRODUCTION

2.0 REVIEW OF THE GEOLOGY OF THE AREA

2.0.1 STRATIGRAPHY OF THE BASIN

2.0.2 TECTONIC HISTORY OF THE BASIN

2.0.3 PALEOENVIRONMENT OF THE AREA

3.0 ECONOMIC SIGNIFICANCE OF AGBAJA IRON ORE

4.0 LEVEL OF EXPLORATION OF THE RESOURCES

5.0 REFERENCES


1.0 INTRODUCTION

In today’s competitive world, identifying and exploit your areas of comparative advantage is the

key to survival. The solid minerals industry holds the greatest potential apart from the

Agricultural sector towards the attainment of the vision 20:2020 which is geared at placing

Nigeria amongst the top 20 economies of the world by the year 2020 because of the rich mineral

deposit in commercial quantity scattered in different parts of the country.

One of such mineral in Nigeria is Iron ore. There are over 3 billion tones of iron ore found in

Kogi, Enugu, Niger, Zamfara, and Kaduna States. The large deposit of oolitic iron ores of Kogi

and Enugu States are yet to be fully explored. Iron ore is used for making steel, transformer, and

motor cars, ferrous sulphate from waster liqueur of the steel picking process or by the direct

reaction, metals for electrical shielding, electro-magnetic devices, electric bells, electric fan cage,

equipment rack, instrument body, engineering works, hydrated salt, iron oxide pigments, various

salts of iron and ferrites and chemicals.

The Agbaja Formation hosts an extensive, shallow, flat-lying channel iron deposit and Mineral

Resources currently estimated at 586 million tonnes at 41.3% Fe (within EL12124) (Agbaja

Mineral Resource). The majority of the Mineral Resources are classified as Indicated (466

million tonnes at 41.4% Fe), the balance are classified as Inferred (120 million tonnes at 41.1%

Fe). The Agbaja Mineral Resource is one of the highest grade beneficiable iron ore resources in

West Africa, yet the current resource covers only 20% of the Agbaja town area within EL12124

that is considered prospective for channel iron mineralisation.


Table 1: Estimated Iron Ore in Nigeria

The rate of steel consumption of a Nation is a direct reflection of the economical and

technological advancement of such a Nation and if Nigeria is to increase her steel consumption

from its current level, massive investment in the exploitation and processing of iron ore is

required.

The Agbaja town where appreciable amount of ironstone is exposed lies 15 km northwest of the

city of Lokoja in Kogi State, and 165 km south west (highway) from Nigeria’s capital city of

Abuja. Lokoja has reticulated electrical power, cellular telephone networks, primary and

secondary schools, hospitals and other amenities. Abuja, being the political capital of Nigeria is a

well-established and serviced city; it has a large international airport with daily flights to Europe,

the middle-east and other African nations and is connected to Abuja by a well maintained duel

carriageway tarmac road (driving time ~2 hours). Importantly, Agbaja is proximal to existing,

under-utilised river and port infrastructure suitable for the transport of bulk commodities (such as

iron ore concentrate).

Nigeria is one of the richest countries of the world as far as mineral resources are concerned, iron

ore inclusive. The estimated workable iron deposits stand in excess of 2.5 billion tonnes most of

which belong to hematite, magnetite, hematite-geothite and siderite-geothite. (Alafara et al.,

2005) Iron is the sixth most abundant element in the universe and the most abundant metal in the

earth’s crust after aluminum. However, Agbaja iron ore has an estimated reserve of over 1 billion

tones (Alafara et al., 2005). The utilization of Agbaja iron ore is hampered by its poor response


to established industrial beneficiation techniques. This is as a result of fine grained texture of the

Agbaja iron ore (Uwadiale and Whewel, 1988).

Figure 1: Extraction of Iron Ore

The channel iron deposit of the Agbaja mine is located within the sub-horizontal to very shallow

east dipping Late Cretaceous Agbaja Formation, which is made up of an upper unit hosting

ferruginous sandstone and oolite/pisolite material (Laterite unit).

The Agbaja Ironstone studied covers some part of Koton-karfe sheet 227 SE and lies within

latitudes 8° 7′ 00′′ - 8° 10′ 30′′ N and longitudes 6° 48′00′′E - 6° 52′00′′E. It occurs within the

upper cretaceous sedimentary sequences of the Bida basin.

2.0 REVIEW OF THE GEOLOGY OF THE AREA

The Bida Basin, also known as the Mid-Niger or Nupe Basin, is located in west-central Nigeria

(fig. 2). Bida Basin is a linear intracratonic sedimentary basin located in central Nigeria


extending from Kontagora in Niger State of Nigeria to areas slightly beyond Lokoja in the south

(fig. 3). It trends NW – SE and lies approximately perpendicular to the Benue Trough. It is

separated from the basal continental bed of the Sokoto Basin by a narrow outcrop of the

crystalline basement rocks in the west and it is adjacent to the Anambra Basin in the east (fig. 2).

Often, experts working in the area have divided the basin geographically into northern and

southern Bida basins probably due to rapid facies changes across the basins. The wrench fault

tectonic model of which postulated the Bida Basin as strike slip feature is based on facies

distribution and evidence of syn-depositional basin floor lowering. The northern and southern

Bida (fig. 3) basins comprises of about 3km thick Campanian to Maastrichtian continental to

shallow marine sediments.

Figure 2: Geological Map of Nigeria Showing Bida Basin (Obaje 2009)


Figure 3: Geology and location of the Bida Basin and Environs

(Obaje et. al., 2011)


Figure 4: Geological map of the southern Bida Basin (Modified from Ojo and

Akande, 2009)

2.0.1 STRATIGRAPHY OF THE BASIN

The stratigraphic succession of Bida basin, collectively referred to as the Nupe Group

(Adeleye, 1974) comprises a twofold Northern Bida sub - basin and Southern Bida sub - basin or

Lokoja Sub- Basin (fig. 10). The basin fill comprises a northwest trending belt of Upper

Cretaceous sedimentary rocks that were deposited as a result of block faulting, basement


fragmentation, subsidence, rifting and drifting consequent to the Cretaceous opening of the South

Atlantic Ocean.

2.0.1.1 Southern Bida Basin

2.0.1.1.1 Lokoja Formation

Lithologic units in this formation range from conglomerates, coarse to fine grained sandstones,

siltstone and claystones in the Lokoja area. Sub-angular to sub-rounded cobbles, pebbles and

granule sized quartz grains in the units are frequently distributed in a clay matrix. Both grain

supported and matrix supported conglomerates form recognizable beds at the base of distinct

cycles at outcrops. The sandstone units are frequently cross-stratified, generally poorly sorted

and composed mainly of quartz plus feldspar and are thus texturally and mineralogically

immature. The general characteristics of this sequence especially the fining upward character,

compositional and textural immaturity and unidirectional paleocurrent trends, suggest a fluvial

depositional environment dominated by braided streams with sands deposited as channel bars

consequent to fluctuating flow velocity. The fine grained sandstones, siltstones and clays

represent flood plain overbank deposits. However, Petters (1986) reported on the occurrence of

some diversified arenaceous foraminifers from clayey intervals of the Lokoja Formation

indicating some shallow marine influence. These foraminifera microfossils identified by Petters

(1986) are however more common in the overlying Patti Formation where shallow marine

depositional conditions are known to have been more prevalent.

2.0.1.1.2 Patti Formation

Outcrops of the Patti Formation occur extensively on the Agbaja Plateau and Ahoko and

Abaji on the Lokoja-Abuja expressway. This formation consists of sandstones, siltstones,

claystones and shales interbedded with bioturbated ironstones. Argillaceous units predominate in

the central parts of the basin. The siltstones of the Patti Formation are commonly parallel

stratified with occasional soft deformational sedimentary structures (e. g. slumps), and other

structures as wave ripples, convolute laminations and load structures. Trace fossils (especially

Thallasinoides) are frequently preserved. Interbedded claystones are generally massive and

kaolinitic, whereas the interbedded grey shales are frequently carbonaceous. The subsidiary

sandstone units of the Patti Formation are more texturally and mineralogically mature compared


with the Lokoja Formation sandstones. The predominance of argillaceous rocks, especially

siltstones, shales and claystones in the Patti Formation requires suspension and settling of finer

sediments in a quiet and low energy environment probably in a restricted body of water (Braide,

1992). The abundance of woody and plant materials comprising mostly land-derived organic

matter, suggests prevailing fresh water conditions. However biostratigraphic and paleo-ecologic

studies by Petters (1986) have revealed the occurrence of arenaceous foraminifers in the shales

of the Patti Formation with an assemblage of Ammobaculites, Milliamina, Trochamina and

Textularia which are essentially cosmopolitan marsh species similar to those reported in the

Lower Maastrichtian marginal marine Mamu Formation (the lateral equivalent) in the adjacent

Anambra Basin (Gebhardt, 1998). Shales of the Mamu Formation on the southern side of the

Anambra Basin are commonly interbedded with carbonates and overlain by bioturbated

siltstones, sandstones and coal units in coarsening upward cycles toward the northern side of the

basin (Akande et. al., 2006). This sequence is overlain by herringbone-cross-bedded mature

sandstones of the Ajali Formation (Middle Maastrichtian) in the northern fringes of the basin

hence providing strong evidence for shallow marine, deltaic to intertidal depositional

environments for the Maastrichtian sediment of the Anambra Basin. The Patti formation,

therefore, appears to have been deposited in marginal shallow marine to brackish water condition

identical to the depositional environments of similar lithologic units of the Mamu and Ajali

formations in the Anambra Basin (Ladipo, 1988; Nwajide and Reijers,1996). The more marine

influences in the adjacent Anambra Basin is probably related to the nearness of that basin to the

Cretaceous Atlantic ocean prior to the growth of the Niger Delta.

2.0.1.1.3 Agbaja Formation

This formation forms a persistent cap for the Campanian-Maastrichtian sediments in the

southern Bida basin as a lateral equivalent of the Batati formation on the northern side of the

basin. The Agbaja formation is best exposed on the Agbaja Plateau where it overlies

successively the Lokoja and Patti formations. The Agbaja formation consists of sandstone beds

in this region. The sandstones and claystones are interpreted as abandoned channel sand

overbank deposits influenced by marine reworking to form the massive concretionary and oolitic

ironstones that had been mapped in some details (Ladipo et al., 1994). Minor marine influences


were also reported to have inundated the initial continental environment of the upper parts of the

Lokoja sandstone and the Patti formation (Braide, 1992; Olaniyan and Olabaniyi, 1996). The

marine inundations appear to have continued throughout the period of deposition of the Agbaja

ironstones in the southern Bida basin (Ladipo et al., 1994).

2.0.2 TECTONIC HISTORY OF THE BASIN

The inland basins of Nigeria constitute one set of a series of Cretaceous and later rift

basins in Central and West Africa whose origin is related to the opening of the South Atlantic

(Figure. 11). The upper Cretaceous Bida basin of central Nigeria is sandwiched between the

Precambrian schist belts of the Northern Nigeria massif and the West African craton. Of interest

is the southern part of the basin, which developed in a continental setting, because the facies

architecture of the sedimentary fill suggest a close relation between sedimentation dynamic and

basin margin tectonics (Sokari, 1990). This relationship is significant to an understanding of the

basin`s origin, which has been controversial. A simple sag and rift origin has been suggested, and

consequently dominated the negative thinking on the hydrocarbon prospects of the basin, which

were considered poor. Although distinguishing pull-apart basins from rift basins, based solely on

sedimentological grounds, may be difficult, the temporal migration of the depocenter, as well as

the basin architecture of repeatedly upward-coarsening, show a strong tectonic and structural

overprint that suggests a tectonic framework for the southern Bida basin similar in origin to a

pull-apart basin which was based solely on the sedimentological evidence proved to be a difficult

mechanism (Sokari, 1990).

The Bida basin is a gently down-warped trough whose genesis may be closely connected

with the Santonian orogenic movements of south eastern Nigeria. The basin is a NW-SE trending

embayment, perpendicular to the main axis of the Benue Trough and Niger Delta Basin. It is

frequently regarded as the north-western extension of the Anambra Basin, both of which were

major depocentres during the third major Transgressive cycle of southern Nigeria in Late

Cretaceous. Interpretations of LandSat images, borehole logs, as well as geophysical data across

the entire Bida Basin suggest that the basin is bounded by a system of linear faults trending NW-

SE. Gravity studies also confirm central positive anomalies flanked by negative anomalies as

shown for the adjacent Benue Trough and typical of rift structure (Ojo, 1984; Ojo and Ajakaiye,

1989). The Benue Trough is a failed arm of a triple junction (aulacogen) that existed beneath the


present position of the Niger Delta during the Cretaceous. The trough is filled with over 5000m

of predominantly Aptian to Maastrichtian sediments in the lower, middle and upper Benue

geographical regions. The Lower Benue Trough which includes the Anambra Basin is

considered as the southern extension of the Bida Basin. Initial gravity studies in the Bida Basin

put the maximum thickness of the sedimentary successions at about 3.5 km (Ojo, 1984) in the

central axis. Although the hydrocarbon potential of the basin has not been fully tested; the basin

remains undrilled. Both ground and aeromagnetic studies by several workers have outlined the

basin's configuration (Adeniyi, 1985; Udensi and Osazuwa, 2004). A recent spectral 99 analysis

of the residual total magnetic field values over several sections of the basin reveals an average

depth to the basement rock to be approximately 3.4km with sedimentary thickness of up to

4.7km in the central and southern parts of the basin (Udensi and Osazuwa, 2004). In general,

sediment thickness decreases smoothly from the central portion to the flanks of the basin.

Figure 5: Regional tectonic map of western and central African rifted basins showing the

relationship of the Muglad, Doba and East Niger Basins to Nigerian inland basins. Location of


regional shear zones (marked with half-arrow) and major zones extension (complete arrow) are

shown. (Adapted from Schull, 1988).

2.0.3 PALEOENVIRONMENT OF AGBAJA FORMATION

The Campanian-Maastrichtian Agbaja Ironstone Formation of the Bida basin, Nigeria, forms a

major part of the about 2 billion tons of iron ore reserves of the Middle Niger Embayment. The

ironstone deposits were previously reported to be similar to the Minette-type ironstones because

of their depositional patterns, composition and inferred origin. Four rock-types are recognized

within the Agbaja Ironstone Formation: ooidal pack-ironstone, pisoidal pack-ironstone, mud-

ironstone and bog iron ore. In the ironstones, kaolinite of both the groundmass and the

ooids/pisoids is of lateritic origin (figure 6), whereas the associated quartz, mica and heavy

minerals are of detrital origin.

Figure 6: Ironstone Bed at Agbaja Area

Ironstone

Bed


Ooids and pisoids were formed by mechanical accretion of platy kaolinite crystals by rolling on

the sea floor in a near-shore environment, and were subsequently transported and deposited

together with a fine-grained kaolinitic groundmass. Pyrite (mainly framboidal) and siderite (both

exclusively occurring as pseudomorphs of goethite and/or hematite) are diagenetic whereas

goethite is post-diagenetic in origin, resulting from the ferruginization of the kaolinitic precursor.

Crandallite-gorxeicite-goyazite, bolivarite and boehmite are also post-diagenetic in origin.

Hematite was formed from the dehydration of goethite, whereas gibbsite (restricted to the upper

part of the deposit) is of recent and in situ lateritic origin. The presence of newly formed

authigenic pyrite and siderite (now replaced by hematite and goethite) are indicators of a

reducing environment during diagenesis.

The absence of diagenetic chamositic clay minerals, evidently caused by a low Mg

concentration, suggests that fully marine conditions were not established during sedimentation.

This is supported by the lack of fossils, brecciated shell materials and bioturbation features in the

deposit. Reworking and redeposition of the primary constituents are inferred from broken

pisoids, nuclei of pisoidal/ooidal fragments in pisoids and high iron concentrations present in the

pisoids and ooids compared to that of the groundmass. These observations indicate that the

Agbaja ironstone deposits of the Lokoja study area exhibit some environmental and

mineralogical characteristics that are markedly different from other known deposits of Minette-

type, where primary chamositic clay minerals generally form the protore for the ironstones. The

recognition of kaolinite as the precursor constituent and the occurrence of similar deposits of the

same age (Late Cretaceous) in Nigeria, Sudan and Egypt have implications for the

paleoenvironmental interpretations of Phanerozoic ironstone deposits.

3.0 ECONOMIC SIGNIFICANCE OF AGBAJA IRON ORE

Kimberly (1994) defined ironstone as any sedimentary rock with total iron content greater than

15%. High grade iron is obtained from ironstone deposits around the world. Iron ores are usually

found in the form of magnetite (Fe3O4), haematite (Fe2O3), goethite (FeO(OH), limonite

(FeO(OH).n(H2O) and siderite.( FeCo3 ). Iron ore is the raw material used to make pig iron

which is one of the main raw materials of steel. Ninety-eight percent (98%) of the iron ore mined

globally is used to make steel (Wikipedia, 2010). The deficiency in iron content shown by many

ores is due to the presence of impurities. These impurities include silica, phosphorous, sulphur


and titanium. Sulphur and phosphorous are deleterious impurities in iron and steel industry

(Onyemaobi, 1998). Silica is objectionable because it displaces iron and so much lime is required

to flux it. Titanium is undesirable because it drives much of the iron in a furnace to the slag.

Magnetite iron ore deposits generally grade around 25-40% Fe, however the Agbaja Mineral

Resource is a unique sedimentary hosted magnetite deposit with a resource grade averaging

41.3% Fe, which with selective mining of higher grade material will provide a feed head grade of

45.7%, ranking it in the top quartile of magnetite projects world-wide with respect to resource

grade.

Magnetite deposits are typically found in banded ironstone formations (BIFs), however Agbaja is

unique in that it is a channel iron deposit (CID), with only two known similar deposits of this

kind in the world. Typical BIF magnetite deposits require large amounts of energy intensive

grinding to liberate the iron from its associated natural matrix, however the Agbaja CID material

is relatively soft and friable and only requires moderate grinding, simple magnetic separation,

and only a coarse grind particle size to liberate the iron. Consequently mining and processing

costs for the Agbaja project are relative low compared to other magnetite projects. Agbaja

estimated total operating costs rank in the bottom quartile when compared to operating costs of

all other magnetite projects.

4.0 LEVEL OF EXPLORATION OF THE RESOURCES

Kogi Iron Limited (Kogi, Kogi Iron or the Company) is an Australian company with the

objective of becoming an African iron ore producer through the development of its 100% owned

Agbaja iron ore project located in Kogi State, Republic of Nigeria, West Africa (Agbaja or

Agbaja Project). The Company holds 17 iron ore exploration licences in Kogi State, with the

main focus being EL12124, which covers more than half of the Agbaja Plateau and within which

is the Agbaja iron ore deposit. This Preliminary Feasibility Study (PFS) assesses the technical

and economic viability for the development of an iron ore mining and processing operation at

Agbaja to produce 5.0 million tonnes of upgraded iron ore concentrate per annum.

The project includes the development of an iron ore mining and processing operation capable of

producing five million tonnes (Mt) of upgraded iron ore concentrate per annum. The mine life is

estimated to be 21 years. Environmental and social impact assessment for the project was

http://www.mining-technology.com/features/featureferro-giants--the-worlds-biggest-iron-ore-producers-4280601/


completed in January 2014. The production of iron ore concentrate from is anticipated to start by

the end of 2016 or early 2017.

The iron ore mine is located on the Agbaja plateau, approximately 15km northwest of Lokoja

city in Kogi State, and approximately 165km southwest of Abuja, the capital city of Nigeria.

Two mining areas (Stage 1 and Stage 2) have been identified, pits have been designed, and

material movement schedules completed. A proposed processing plant site location has also been

identified; it is in the north east portion of the area covered by the Agbaja Mineral Resource and

was selected based on its central location between the two areas identified for mining operations.

The Stage 1 mining area is approximately 7.2 km2 and is west of the plant site and contains

approximately 158 Mt of Indicated Mineral Resources. Targeting the magnetic fraction of the

Indicated Mineral Resource, the average grade of material identified for mining is estimated at

46.1% Fe, with a corresponding strip ratio of approximately 0.55 to 1. As currently designed this

area will provide processing plant feed for an initial 15 years at the planned concentrate

production rate of 5 Mtpa.

The Stage 2 mining area is approximately 2.2 km2 and is to the east of the plant site. This area

is estimated to contain approximately 66 Mt of the Indicated Mineral Resources. The average

grade of material is estimated at 44.8% Fe, with a strip ratio of approximately 0.56 to 1. This

area will provide processing plant feed for an additional 6 years, bringing the combined plant

feed from the two areas to 21 years (at concentrate production rate of 5 Mtpa).

With a life-of-mine average strip ration of 0.55 to 1 (on Indicated Mineral Resources), mining

costs for the 21 years of operations will be low, a distinct advantage of the project.

Kogi has opted for a mining contractor to conduct all site development, overburden and waste

removal, open-pit mining including site rehabilitation, haulage and ore feed to a primary crusher.

Mining operations will be conducted on a 24/7, 365 days per year basis and it is envisaged that

production drilling and blasting will not be required, as all material is regarded as soft and

friable, and amenable to “free-dig”.

http://www.mining-technology.com/projects/kararamine/


5.0 REFERENCES

ADELEYE, D. R., 1974. Sedimentology of the fluvial Bida Sandstones (Cretaceous) Nigeria.

Sedimentary Geology 12, 1-24.

ADENIYI, J. O., 1985. Ground total magnetic intensity in parts of the Nupe Basin and the

adjacent basement complex, Niger State, Nigeria. Nigerian Journal of Applied Science 3,

6778.

AKANDE, S. O., OJO, O. J., ADEKEYE, O. A. AND LADIPO, K. O., 2006. A Geological

Field Guide to the Southern Bida Basin. Nigerian Association of Petroleum

Explorationists (NAPE), 24th Annual Conference and Exhibition, Abuja, 21pp.

ALAFARA, A.B., ADEKOLA F.A.O., AND FOLASHADE A. O., 2005. Quantitative

leaching of a nigerian ore in hydrochloric acid. Journal of Applied science and

Environment, 9(3): 15-20.

BRAIDE, S. P., 1992. Syntectonic fluvial sedimentation in the central Bida Basin. Journal of

Mining and Geology, 28, 5564.

KOGI IRON LIMITED 2014. In-house report on the positive preliminary feasibiliby study of

Agbaja project.

LADIPO, K. O., AKANDE S. O. AND MUCKE, A., 1994. Genesis of ironstones from the

Mid- Niger sedimentary basin: evidence from sedimentological, ore microscopic and

geochemical studies. Journal of Mining and Geology, 30, 161-168.

OBAJE, N. G., 2009. Geology and Mineral Resources of Nigeria. Springer, Heidelberg, 221pp.

OBAJE, N. G. MOUMOUNI, A. GOKI, N. G., AND CHAANDA, M. S., 2011. Stratigraphy,

Paleogeography and Hydrocarbon Resource Potentials of the Bida Basin in North-Central

Nigeria, Journal of Mining and Geology Vol. 47(2), pp. 97–114

OJO, S. B., 1984. Middle Niger Basin revisited: magnetic constraints on gravity interpretations.

Abstract, 20th Conference of the Nigeria Mining and Geosciences Society, Nsukka, pp.

5253

OLANIYAN, O. AND OLOBANIYI, S. B., 1996. Facies analysis of the Bida Sandstone

Formation around Kajita, Nupe Basin, Nigeria. Journal of African Earth Sciences, 23,

253-256.


OMALI A.O., IMASUEN, O.I AND OKIOTOR M.E., 2011 Sedimentological Characteristics

of Lokoja Sandstone Exposed At Mount Patti, Bida Basin, Nigeria, Advances in Applied

Science Research, 2 (2):227-245

NWAJIDE, C. S. AND REIJERS, T. J. A., 1996. Sequence architecture in

outcrops: examples from the Anambra Basin, Nigeria. Nigerian Association

of Petroleum Explorationists Bulletin, 11, 2333.

PETTERS, S. W., 1986. Foraminiferal biofacies in the Nigerian rift and continental margin

deltas. In: OTI, M. N. and POSTMA, G. (Eds.) Geology of Deltas. AA Balkema,

Rotterdam, pp219-235

SCHULL, T. J. (1988) Rift basins of interior Sudan: Petroleum exploration and discovery.

AAPG Bulletin 72, 1128–1142.

SOKARI P. B. (1990). Sedimentation and tectonics in the Southern Bida Basin, Nigeria:

Depositional response to varying context. AAPG Search and Discovery Article

#91003©1990 AAPG Annual Convention, San Francisco, California

UDENSI, E. E. AND OSASUWA, I. B. (2004). Spectra determination of depths to magnetic

rocks under the Nupe Basin, Nigeria. Nigeria Association of Petroleum Explorationists

Bulletin, 17, 22-37.

UWADIALE, G. G. AND WHEWEL R.S., 1988. Effect of temperature on magnetizing

reduction of agbaja iron ore. Metallurgical Transition B, 19B(731 – 785).

iron ore deposits in agbaja area by professor olatinpo o.a

Documents

estimated iron ore

processing of iron ore

tones of iron ore

channel iron deposit

mineral resources

channel iron mineralisation

iron oxide pigments

various salts of iron