NIGERIAN GEOLOGICAL SURVEY AGENCY. By DAVID IFEOLUWA ANDREW U18GL1011 CONTENTS About NGSA/Introduction Skills Acquired Introduction Soil Sampling Equipments Sampling Techniques Results & Importance of Soil Sampling. Conclusion About NGSA/Introduction NGSA was created under the federal ministry of solid minerals with statutory role of providing relevant and up to date geoscientific data in the form of maps, journals and electronic information. This is accomplished through many activities carried out within the agency. These activities includes; Geophysical Survey Geochemical Sampling methods Geological Sampling Hydrogeological survey Remote sensing Map Production Geochronology etc Skills Acquired Gravity Survey Method Geological Sampling Geochemical Sampling Map Production Introduction to Geological & Geochemical Sampling Sampling of minerals deposit Is an important aspect of geochemical and Geological exploration. A geological sample is a representative unit of a soil, rock or ore that is selected from a large mass. Geochemical & Geological sampling simply involves collecting and analysing various earth materials obtained from field including Soil, sediments, water, vegetation & rocks samples for geological analysis. And all these is in a bid to determine the mineralogy, composition and grade 0f minerals. Geochemical Sampling Types Stream Sampling Soil sampling Rock sampling Vegetation sampling. etc Main Focus on Field Soil sample being bagged. Rock Sample Rock Sample Soil Sampling Soil Sampling: is widely used in Geochemical sampling and involves getting or collecting soil samples in field which are then analyzed in the laboratory. Soil Sampling is employed mainly to outline the general distribution of mineralization at shallow depth where outcrop of bedrocks are minimal or non existent. Images of part of the study area Soil Sampling Desktop Research, Team talk and review of previous work, Field work; Sampling, sorting and data compilation. The Soil sampling was carried out in a grid pattern to delineate the mineralized zone which is expected to be of GOLD MINERALIZATION and parameters considered are Sample spacing, Sample Horizon, Sample Fraction to be analyzed and method of sample analysis. Grid Map. Geological Map of The Sample Location Points Equipment Used during the course of the field work Geological Compass Auger GPS Device Geologic hammer Soil sampling techniques Augering & Pitting for the soil sediments An auger is a simple tool usually carrying an arrow at the tip and is used to make HOLES within the soil in order to get fresh soil samples which are then bagged in well-labelled sample bags. Supervision of Augering process on the field Sampling techniques Pitting: involves digging pits (about 1m deep) seldomly within the study area in order to get fresh samples and determine the thickness of the observable horizon and also logging. Measurements of Horizon thickness from the Pit Results Legend depth(m) description 0-0.3 Soil is loose, fine grained 0.3-0.7 soft, white, sand. 0.7-1.1 medium-dense to dense soil, with clay properties. An Example of a soil log from one of the pits Results Concentration Map of the Study Area. Discussion Soil sampling is a cheap and effective way of kick-starting a mineral exploration programme over an area previously highlighted by historical mineral occurrences, mapping/prospecting or regional airborne geophysical surveys. However, for areas which may have the potential for hosting a large ore body, soil sampling may be followed up by a closerspaced soil sampling survey, and – if this also proves interesting – eventual drilling. Conclusion The success of the field work provided sufficient data that would be worked on to produce quality and up to date geoscientific information about the study area. NGSA helped bridge the gap between what I have been learning in class and how it can be applied on the field. I was able to properly appreciate geology as a professional course and understand some of the risks associated with it. THANK YOU FOR LISTENING…