This work produces some vital geologic information on the geology and structural analysis of rocks mapped around Kanwara, Dass local government area of Bauchi State. The mapped area is located between longitude N10001’09” and N1O000’09”and latitude E9032’42” and E9031’26”. Exposure of rocks in the area were mostly high level and medium level outcrops with only a few low level outcrops, the high level outcrops were conically shaped with height ranging between 400m to 700m above sea level while the inselberg was about 900m. The predominant rock types in the area were granite gneiss, biotite granite and migmatite, under thin section, minerals were identified via their respective optical properties under both plane polarized light and cross polarized light, the major minerals associated with the rocks were; biotite, quartz, feldspars, (orthoclase & plagioclase), muscovite and microcline. Based on field observations, the geologic structures found on the rocks include; joints, foliations, minor folds, ghost schist, dykes and veins. The joints indicate the masking effect of the pan African orogeny on the older granites (trending NW-SE). The shape of the girdle from the structural analysis conducted indicates that the rocks of the mapped area were subjected to medium grade metamorphism.
Table of Contents
1.0 Introduction
1.1 Aim of study
1.2 Location and accessibility
1.3 Relief and drainage
1.4 Climate and vegetation
1.5 Settlement and land use
2.0 Review of the geology of the Precambrian to lower Paleozoic rocks of northern Nigeria
2.1 The Paleozoic and Precambrian rocks in northern Nigeria
2.2 Intermediate rocks from older granite complex
2.3 Field relations in Dass
3.0 Materials and Methods
3.1 Field equipment
3.2 Sample collection
3.3 Measurements of strikes and dips
3.4 Study of rock samples
3.5 Procedures for structural analysis (stereographic projections)
4.0 Macroscopic and microscopic studies
4.1 Macroscopic study of samples A
4.1.1 Microscopic study of sample A ([plate I)
4.1.2 Statistics of sample A (plate I)
4.2 Macroscopic study of Samples B
4.2.1 Microscopic study of sample B ([plate II)
4.2.2 Statistics of sample B (plate II)
4.3 Macroscopic study of Samples C
4.3.1Microscopic study of sample C ([plate III)
4.3.2 Statistics of sample C (plate III)
4.4 Macroscopic study of Samples D
4.4.1Microscopic study of sample D ([plate IV)
4.4.2 Statistics of sample D (plate IV)
4.5 Macroscopic study of Samples E
4.5.1Microscopic study of sample E ([plate V)
4.5.2 Statistics of sample E (plate V)
4.6 Summary of the petrography
4.7 Structural geology
4.8 Structural Analysis
5.0 Results and Summary
Conclusion
Geological Map of the study area
Recommendations
Reference
Research Objectives and Focus Areas
This study aims to provide geological insights into the Kanwara region of Dass, Bauchi State, specifically focusing on structural analysis, rock classification through petrographic evaluation, and the assessment of deformation levels via stereographic projections to contribute to the existing knowledge of the area's geology.
- Structural geology and mapping of major rock types in the Kanwara area.
- Petrographic analysis of rock samples and mineral identification under thin sections.
- Application of stereographic projections to determine the type and level of rock deformation.
- Analysis of tectonic structures, including joints, foliations, and minor folds, to understand the influence of Pan-African orogeny.
Excerpt from the Book
4.6 Structural Geology
The area mapped which forms part of the Nigerian basement complex is Affected by the pan-African (about 550ma) and older orogenesis. However the pan African orogeny tends to erase the imprints of the other orogenies in the area, therefore, its effect overshadowed those of the older orogenies in the area.
Based on field observations, the geologic structures observed in the area include joints, foliations, minor folds, ghost shist structure and dykes & veins.
4.6.1 Joints
These are the most prominent of all the tectonic structures found in the area, however, they were only observed on the gneisses. They occur mostly as tight fractures, however, in many cases fissured joints were observed due to weathering. Vegetation usually grows along the trend of such fissures which suggest that they are water conduits (Figure 11). Most of the joints were in multiple of twos or threes that is joint set. The joints show variable trends from NW-SW. The NE-SW trends were dominant and therefore shows masking effect of the Pan-African orogeny on the older granites (striking NW-SE).
Summary of Chapters
1.0 Introduction: Outlines the research aims, objectives, and geographical setting of the study area in Kanwara, Dass.
2.0 Review of the geology of the Precambrian to lower Paleozoic rocks of northern Nigeria: Provides a comprehensive literature review of the geological framework and tectonic history of Northern Nigeria.
3.0 Materials and Methods: Describes the field techniques, equipment, and laboratory procedures used for petrographic analysis and structural data processing.
4.0 Macroscopic and microscopic studies: Details the petrographic investigations and structural analysis of the collected rock samples, including statistical mineral assessments.
5.0 Results and Summary: Synthesizes the petrographic findings and structural analysis data, concluding on the deformation and metamorphic grade of the area.
Keywords
Geology, Structural Analysis, Foliation, Granite Gneiss, Kanwara, Bauchi State, Petrography, Stereographic Projection, Basement Complex, Pan-African Orogeny, Metamorphism, Joints, Migmatite, Biotite Granite, Tectonics.
Frequently Asked Questions
What is the primary focus of this thesis?
The thesis focuses on the geological and structural analysis of rocks exposed in the Kanwara area of Dass, Bauchi State, Nigeria.
What are the central thematic areas?
The central themes include petrographic study of rock types, structural mapping of tectonic features, and the interpretation of rock deformation history.
What is the main research objective?
The main objective is to produce vital geological information, develop a local geological map, and determine the level of deformation in the area using stereographic projections.
Which scientific methods were employed?
The work involved field reconnaissance and mapping, petrographic analysis of rock thin sections using optical properties, and statistical structural analysis via Schmidt nets.
What is covered in the main body of the work?
The main body covers a literature review of Precambrian rocks, detailed methodology, macroscopic and microscopic examination of specific samples (A-E), and structural geological analysis.
Which keywords characterize this research?
Key terms include Geology, Structural Analysis, Foliation, Granite Gneiss, Basement Complex, and Pan-African Orogeny.
What did the structural analysis reveal about the rocks?
The structural analysis, particularly the S-pole diagrams and girdles, indicates that the rocks in the mapped area were subjected to medium-grade metamorphism.
How were the mineral statistics calculated?
Mineral statistics were determined by counting identified minerals in thin sections across different microscope positions and calculating their percentage distribution within the bulk rock.
- Citar trabajo
- Umar Sambo Umar (Autor), 2011, Geology and Structural Analysis of Foliation Planes of Granite Gneiss exposed around Kanwara, Dass. Bauchi State, Múnich, GRIN Verlag, https://www.grin.com/document/284388
