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Grain Size Distribution Analysis

Grain Size Distribution Analysis is usually employed in sedimentology. It is employed to determine the size of the different grains that make up a sedimentary rock or soil unit under consideration.

From the analysis, the following can be deduced:
            The sortability of the grains;
            The environment of deposition (Paleoenvironmental reconstruction);
            The energy of deposition (Paleocurrent current reconstruction);
            Transportation agent.
Please note that this analysis does not in any way show / determine the mineralogical composition of the rock / soil unit.
Grain sizes range from gravel (conglomerates and coarser particles) to clay (fine particles). It is determined by its diameter and measured in millimeters (mm), micrometers (µm) or phi (ø).
Below are the soils ranges (in mm):             Boulders                                              >200             Cobbles                                               63-200             Gravel (Coarse)        …

WHY ENVIRONMENTAL IMPACT ASSESSMENT

WHY ENVIRONMENTAL IMPACT ASSESSMENT
Is there really any need for an Environmental assessment at all? By the way, what is an Environmental Impact Assessment (EIA for short)? It is an assessment conducted to ascertain the potential effect of a project that is to be sited in a place. The assessment is to appraise whether it will be harmful to the host community or otherwise and the international best practice to adopt.

Activities like mining, quarrying, oil exploration, dredging, citing of power plants, nuclear plants and factories, etc, all requires an EIA before taking off. In some cases, EIA can also be carried out for an already existing project. It is sometimes called Environmental Study, Environmental Impact Statement or Environmental Effect Study.

History has it that EIA was first introduced in 1969 in the United States of America as an Act. Since then, it has been adopted and fine tuned by increasing number of countries to suit them.

It is a norm in most countries of the world and it…

DIFFERENCES BETWEEN A ROCK AND A MINERAL

There are some facts one may think he knows in Geology but…oops! They are really obfuscating. The look so elementary that they are easily jettisoned.

A Rock is an aggregate of naturally occurring minerals.
A Mineral is an inorganic, crystalline and naturally occurring substance with a definite chemical composition.
Physical Properties of Minerals
Hardness (measured in Mohs Hardness Scale). It increases downwards.
Talc (softest)
Gypsum
Calcite
Fluorite
Apatite
Orthoclase
Quartz
Topaz
Corundum
Diamond
Luster: is the manner the mineral reflects light.Color: each mineral has its basic colour for which it is known. But this is usually deceptive.Streak: The color of the mineral in powdered form.Cleavage: How the Mineral breaks along its plane of weakness.Fracture: How the mineral breaks unevenly.

Your Safety And Your Job

It has always been an issue on how best to stay safe in our environment especially in work places coupled with the fact that jobs are much demanding and hectic.

You can’t talk of safety if there is no likelihood of an accident occurring either before, during / or after.
Accident is an unplanned happenstance that occurred as a result mistake, carelessness, or even negligence of a staff(s) in a company. The accident may give rise to small / minor injuries or may lead to death as the case may be.
By WHO standard, ‘Occupational health (your safety and your job) should aim at the promotion and maintenance of the degree of physical, mental and social well-being of workers in all occupations; the prevention amongst workers departures from good health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychol…

The Importance Of Geophysics In Groundwater Investigation

Before we delve into this, we need to first of all define some terms.
What is Geophysics?      It is the use of Physics to solve Geology problems.
What then is Geology?  Simply the study of the Earth. This includes the structure and the rocks.
Geophysics is usually employed when it involves probing the subsurface. In physical Geology, you are dealing with the surface geology, i.e. the structures, forms, and the lithofacies that are visible on the surface.
To solve environmental issues, mining, archeological, engineering (Geotechnical) and geological (hydrogeological) problems, geophysics is employed. It is achieved by passing an electric current via two current electrodes and the potential drop between the two current electrodes is measured by a voltmeter. From this, the resistance is deduced. Here, the current (I) is already known and the potential drop (V) is known as well. Given the formula:           V=I×R                                                                           -…

TYPE OF FOUNDATIONS FOR ENGINEERING STRUCTURES.

For every super structure, there must be an underlying substructure. This substructure is also known as foundation. The essence of the substructure is to transmit the load of the superstructure to the ground and make it firm.
There are broadly two (2) types of foundations:
Shallow FoundationsDeep Foundations
Shallow foundation is any foundation that is between 1m to 3m. it is very near to the surface.
Deep foundation is any foundation that is beyond 3m.
The type of the foundation to be chosen is dependent on the type of superstructure to be erected and the load bearing capability of the soil in that place. These factors have to be determined by a competent Engineering Geologist.
Shallow foundation includes:
Strap footings. This is also called Cantilever footings. Here, two single footings are connected with a beam.



Mat footings. Are mostly used in cases where the soil is so weak and the building loads extensive. A mat is a flat concrete slab massively reinforced with steel. The load…

REASONS WHY BUILDING STRUCTURES FAIL

Building structures fail because there is a failure already in the foundation. It is always advisable to get it right at the first time than seeking for a remedy when the unexpected happens.
Getting it right the first time is by far cheaper and less stressful than seeking for a remedy when the unexpected happens. Nothing can be used to compare a quality foundation that can comfortably carry a superstructure despite the cost.
In some instances, the cost of a foundation can triple that of the superstructure itself especially in reclaimed lands, lands where mining has taken place, clayey soils, lands previously used for refuse dump, etc.











It is always necessary to seek the help of a competent Engineering Geologist to advise you on the best and cost effective foundation type to embark on.


Fig 1: A failed fence caused by soil heaving.

Foundations fail because of the differential settlement of the soil upon which it was built. This in turn leads to the failure of the superstructure.
The following …

EFFECTIVE WASTE MANAGEMENT

Every living thing on earth generates waste and it is a thing of great concern to our ecosystem. These wastes vary one from the other depending on their composition. Some wastes are harmless (take for example the release of Oxygen by green plants during photosynthesis) while others are harmful.

Waste can be generally defined as any unwanted material or substance that is (or may be) detrimental to its host. Wastes can be unusable or unwanted items in our homes / offices / industries, remains, by-products, garbage, excreta and dung, used or contaminated water from domestic, industrial or mining applications.




Fig 1: Open defecation in an abandoned plot of land. The person is circled red in this picture.


The excreta will get leached down into the ground and this in turn pollutes the surface aquifer.
The greatest killer of our ecosystem is urbanization / industrialization. Trees that are supposed to check green house gases and erosion are fallen down and probably sawn into woods to give way…