GRAVITY AND MAGNETIC STUDIES OF THE SUB-BASALT CASSITERITE DEPOSIT IN PLATEAU STATE, NIGERIA

Simple item page
dc.contributor.authorAVJAJIOKAN, ENOCH IKPOKONTE
dc.date.accessioned2014-02-26T09:40:06Z
dc.date.available2014-02-26T09:40:06Z
dc.date.issued1984-10
dc.descriptionA THESIS SUBMITTED TO THE POSTGRADUATE SCHOOL, AHMADU BELLO UNIVERSITY, IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE, APPLIED GEOPHYSICS. DEPARTMENT OF PHYSICS, AHMADU BELLO UNIVERSITY, ZARIA-NIGERIA. OCTOBER 1984en_US
dc.description.abstractA detailed gravity and magnetic survey carried out on the N'Gall basalt area of Jos Plateau region, was aimed at studying which analytical technigue is practically suitable to the exploration of sub-basalt deposits, with a view to estimating the basalt thickness and removing its masking effect from the acguired data in problem areas such as the sub-basalt cassiterite fields. It was thought that this approach will further reveal a knowledge of the relative variation of the bedrock surfaces, tne v/eathered/v/eak zones of the bedrock, and the ancient river channel along which tin-bearing sands are believed to be deposited and later covered by sediments overlain by thick hard basalt flow. Results show that the area of investigation includes a possible downstream extension of the ancient N'gell river flowing to the NE-SW direction into a basement low surface, resulting into a thick pile of sediments, later covered by basalt flow and compacted. Dopth estimates from the potential field sources are comparable with those done on an available control borehole section and are in aggreement with the borehole results. The basaltic layer thicknesses obtained from gravity data ranges from 10 to 29 m„, and from magnetics a range of 11 to 40 m. Statistical correlation of both results is fair (0.44 to 0.99). The basalt overburden depth from gravity ranges from 9 - 36 m. with an average of 16 m. while estimate from magnetics ranges from 14 - 21 m. with average of 17 m. B' ::'-!t overburden, depths was then fairly obtained from total field magnetic data and compared with those from gravity. The gravimetric depths to basement ranges from 60 - 80 m. with an average of 65 m. and a range of 47 - 69 m„ was obtained from magnetic data. An estimate done on gravity gradients in the area yielded a depth range (to source) of 32.4 - 44„5 m» with an average of 38.0 m. which is indicative of the approximate depth to the base of basaltic layer and is in aggreement with the: borehole results. From these results, it was then possible to remove the basaltic masking effect from gravity data observed on the basalt, by a stripping technigue and this enabled a fair estimation of approximate depths to sub-basalt bedrock -and'interpretation of the sub-basalt basin outline. From the stripped gravity data then, bedrock depths ranges from (49 - 65) m„ in the north - western part of the study area; (52 - 100) m. with bedrock dipping towards south-west in the middle part, and a range of (45 - 70) m. in the south-eastern part of the study area. The sub-basalt sedimentary thickness ranges from 10 - 30 m. in the north-western part, 30 - 80 m. in the middle part, with average of 70 m. and 3 - 30 m. withen_US
dc.identifier.urihttp://hdl.handle.net/123456789/2739
dc.language.isoenen_US
dc.subjectGRAVITYen_US
dc.subjectMAGNETICen_US
dc.subjectSTUDIESen_US
dc.subjectSUB-BASALTen_US
dc.subjectCASSITERITEen_US
dc.subjectDEPOSITen_US
dc.subjectPLATEAUen_US
dc.subjectNIGERIAen_US
dc.titleGRAVITY AND MAGNETIC STUDIES OF THE SUB-BASALT CASSITERITE DEPOSIT IN PLATEAU STATE, NIGERIAen_US
dc.typeThesisen_US
Files
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
GRAVITY AND MAGNETIC STUDIES OF THE SUB-BASALT CASSITERITE DEPOSIT IN PLATEAU STATE, NIGERIApdf.pdf
Size:
5.08 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.58 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
SCIENCE