Pages

Astronomers create first realistic virtual universe


Move over, Matrix -- astronomers have done you one better. They have created the first realistic virtual universe using a computer simulation called "Illustris." Illustris can recreate 13 billion years of cosmic evolution in a cube 350 million light-years on a side with unprecedented resolution.

Stars like the sun may end up alone but they are born in stellar nurseries, with a thousand — or a hundred thousand — siblings. Over time, the family disbands, victims of gravitational nudges and other tidings after 4.5 billion years of life in the cosmos.

Types of Mountains


Mountains make up a large proportion of the earth's surface. Based on their mode of formation, four main types of mountains can be distinguished.

1.     Fold mountains. These mountains are by far the most widespread and also the most important. They are caused by large-scale earth's movements, when stresses may be due to the increased load of the underlying rocks, flow movements in the mantle, magnetic intrusions into the crust, or the expansion or contraction of some part of the earth. When such stresses are initiated, the rocks are subjected to compressive forces that produce wrinkling or folding along the lines of weakness. Folding effectively shortens the earth's crust, creating from the original level surface a series of waves. The upfolded waves are called anticlines and the troughs or downfolds are synclines.

Earth Movements and the Major Landforms


The face of the earth is constantly being reshaped by the agents of denudation - running water, rain, frost, sun, wind, glaciers and waves, so that our present landforms are very varied and diverse. But these agents only modify the pattern of mountains, plateaux and pains which have been modelled by movements of the earth's crust.
Since the dawn of geological time, no less than nine orogenic or mountain building movements have taken place, folding and fracturing the earth's crust. Some of them occurred in Pre-Cambrian times 600-3500 million years ago. The three more recent orogenics are the Caledonian, Hercynian and

Uses of Rocks


Rocks are very important economically. The thin surface layer of the earth, formed by the break-down of the rocks in various ways and by various processes, is known as soil. The geographer is, among other things, interested in the soil as the medium in which plants grow, hence the scene of production of most of man's food and most of his raw materials.
Man's vital water supply is connected with the nature of the rocks. Part of our drinking water is got by sinking wells to tap the sub-surface water which is filtered naturally during its passage through the rocks. The amount of surface run-off in the form of rivers and springs affects the siting of

The Influence of Rock Types on Landscapes


The appearance and characteristic features of landforms are greatly influenced by the underlying rock type. Softer rocks like clay and shale are worn down much faster than harder rocks like granite.
The ancient rocks which dominate a great part of West Africa have been so greatly worn down by erosion that they now appear as peneplains. Granite domes for inselbergs have been formed where the old rocks resist erosion: and in some cases, such resistant high rocks produce high relief, such as the Jos Plateau of Nigeria, the Akwapim-Togo-Atacora ridges and the Birrimian uplands of Ghana, and the interior plateaux and mountains of Sierra Leone, Shales, schists and sandstones, being less resistant, form the much lower, rounded hills. Recent river sediments form flat plains.

Metamorphic Rocks

All rocks whether igneous or sedimentary may become metamorphic or changed rocks under great heat and pressure. Their original character and appearance may be greatly altered by such forces, particularly during intense earth movements. In this manner, clay may be metamorphosed into slate, limestone into marble, sandstone into quartzite, granite into gneiss, shale into schist and coal into graphite.

Sedimentary Rocks


Sedimentary rocks are formed from sediment accumulated over long periods, usually under water. They are distinguished from the other rock types by their characteristic layer formation and are termed stratified rocks. The strata may vary in thickness from a few centimetres to many metres. The rocks may be coarse or fine-grained, soft or hard. The materials that form sedimentary rocks may be brought by streams, glaciers, winds or even animals. They are non-crystalline and often contain fossils of animals, plants and other micro-organisms. Sedimentary rocks are thus the most varied in their formation of all rocks. Sedimentary rocks are classified according to their age and different kinds of rocks formed during the same period are grouped together. It is

Igneous Rocks


Igneous rocks are formed by the cooling and solidification of molten rock (magma) from beneath the earth's crust. They are normally crystalline in structure. They do not occur in strata (layers) nor do they contain fossils. Igneous rocks may be subdivided on the basis of mineral composition. When they contain a high proportion of silica they are said to be acid. Acid igneous rocks, such as granite, are less dense and are lighter in colour than basic rocks. These contain a greater proportion of basic of basic oxides, e.g. of iron, aluminum or magnesium, and are thus denser and darker in colour.
In terms of origin there are two main classes of

The Classification Of Rocks


Rock Texture, Structure and Colour

Rock texture refers to the sizes of the mineral grains, that is, whether the rock is fine grained or coarse grained, dense glass or frothy glass. The texture of an igneous rock varies according to the environment in which solidification took place. Very rapid cooling of lava at the earth's surface results in a glassy texture. Moderately rapid cooling produces fine texture, while coarse textures are as a result of slow or gradual cooling of molten rock deep down in the crust. Textures of sedimentary rocks are recognizable on the basis of the size of the constituent grains and the minerals contained. Shale is a sedimentary rock formed from mud or clay and it is made up of particles of sand size 0.02mm - 2.00mm.
The colours of rocks are essentially a consequence of the minerals which make up the roc

ASUP Strike Federal Government turns blind eyes and deaf ears


Since April, 2013 it has been "strike" "resume" "strike" for ASUP. I will classify the strike action in sections (section A and B). The section A of the strike lasted for three ugly months i.e. from April, 2013 to July, 2013 due to the Senate's intervention, when they promised to wade into the controversy and solve it, but we all saw what happened, "the senate disappeared and was nowhere to be found like the missing Malaysian airplane". The section B of the strike was activated (a sort of reactivation of section A) on October, 2013 till date! How many months now? Do the calculation yourself. Our Education Minister, Nyesom Wike and our President, Dr. Goodluck Jonathan are happy and comfortable with the strike.

When a problem surfaces, a coward runs, but a brave man challenges, controls and solves it.
Since this current and on-going strike of ASUP began, our so called minister of education and the Federal government have done almost nothing to address it. The minister is not even interested in knowing what led to the strike, not to talk of tackling it. He is a disgrace to the Nigerian Polytechnics, Education sector and Nigeria at large. He is not sensitive enough to be in that position as a minister of Education, he terrorises our students, in fact he may be called a "terrorist". Instead of listening to the aggrieved Polytechnic lecturers and reason with them for possible solution to the matter, he is busy attacking them and spreading false information to Nigerians pretending to be solving the issue. Is that what a genuine leader should be doing? Lets think straight here, who are the ones suffering in this battle created by Wike? Our Children, the students, the ones to take over from us. Is this strike neglected because it is the Polytechnics, ASUP that is involved? Is it that what ASUP asks is too much or cannot be tackled? Because to my knowledge, more than 75% of their demand does not involve money, they are just problems killing the Polytechnic Education of this Nation. All the words which have been coming out of the ministers mouth since this strike started were empty and full of deceit and insincerity. He is a coward.
As for the President, Dr? Goodluck Jonathan, he is totally not showing concern, he turned a deaf ear to ASUP and Federal Polytechnics in general. Rather than addressing this strike, he is busy campaigning and preparing for re-election come 2015. I do not know why we keep having cowards as our leaders. May God help this Nation. If this nation is tired of Polytechnic education, let it be erased, if this nation still needs the Polytechnic education, let it be well nurtured and respected.

Whatever problem or monster we created today must surely hunt us or even destroy us tomorrow, whether we like it or not it is a simple truth. Mr. President, Mr. Minister, Please, we beg you in the name of God, let our children, students go back to school, we know your kids are not there but for the sake of this nation, please do your work, that is why you are there.

Emecee
Fed Poly, Oko.

The Structure of the Earth

In order to understand the geography of the external landforms of the earth, it is essential that we have some idea of what lies within the earth's crust. It is not possible to know exactly how the earth was formed about 4500 million years ago, but from the evidence of volcanic eruptions, earthquake waves, deep-mine operations and crutal borings the following facts are quite

Latitude

Latitude is the angular distance of a point on the earth's surface, measured in degrees from the centre of the earth. It is parallel to a line, the equator, which lies midway between the poles. These lines are therefore called parallels of latitude, and on a globe are actually circles becoming

Longitude

Imaginary lines running north/south at right angles to the parallels and passing through the poles are known as lines of longitude or meridians. The line of longitude passing through Greenwich (London) is 0 degrees or the prime meridian (so called because all lines of longitude are numbered east or west from it). The longitude of a place is its angular distance east or west of the Greenwich meridian, measured at the centre of the earth. There are 180 degrees of west longitude and similarly 180 degrees of east longitude. However, since there are 360 degrees in a circle. 180 degrees East and 180 degrees West must be one and the same line. Since the earth is spherical and has a circumference calculated at 40,232.5 km, in linear distance each of the 360 degrees of longitude is 40,232.5/360 or 111.757 km. As the parallels of latitude become shorter polewards, so the meridians of longitude, which coverage at the poles, enclose a narrower space. The degree of longitude therefore decreases in length. It is longest at the equator where it measures 111.318 km. At 25 degrees it is 100.95 km; at 45 degrees it is 78.856 km; at 75 degrees, 28.967 km; and at the poles 0 km. There is so much difference in the length of degrees of longitude outside the tropics, that they are not used for calculating distances as in the case of latitude. But they have one very important function, they determine local time in relation to G.M.T. or Greenwich Mean Time, which is sometimes referred to as World Time.
THE POSITION OF A PLACE
It is necessary to be precise in stating the position of a place in degrees, since there are two latitudes X degrees (X degrees North and X degrees South). Similarly, longitude Y degrees refers to either opposite meridians unless we state it as Y degrees east and Y degrees west.

Longitude and Time

LOCAL TIME. Since the earth makes one complete revolution of 360 degrees in one day or 24 hours, it passes through 15 degrees in one hour or 1 degrees in 4 minutes. The earth rotates from west to east, so every 15 degrees we go eastwards, local time is advanced 1 hour. Conversely, if we go westwards, local time is retarded by 1 hour. We may thus conclude that places east of Greenwich see the sun earlier and gain time, whereas places west of Greenwich see the sun later and lose time. If we know G.M.T., we merely have to add or subtract the difference in the number of hours from the given longitude. A simple memory aid for this will be East-Gain-Add (E.G.A.) and West-Lose-Subtract (W.L.S.). You could coin your own rhymes for the abbreaviations. The local time for Lagos (3 degrees east) will be 12 minutes ahead of London or 12.12 p.m. But the local time for New York (74 degrees west) will be 4 hours 56 minutes behind London or 7.04 a.m. We can put it in another way: when Londoners and Nigerians are having lunch, New Yorkers will have breakfast. This is difficult to believe, but it is true. The rotation of the earth round the sun means that at any point in time different places are experiencing a different time of day.
HOW TO CALCULATE LOCAL TIME
1. Work out the longitude difference.
2. Convert this to a time difference.
3. Adjust the time according to the direction of movement (east or west).
Example. What is the time in Calcutta (longitude 96 degrees east) when it is 9.00 a.m. in Munich (longitude 11 degrees east)?
1. Longitude difference = 85 degrees
2. Time difference 85/15 = 5 hours 40 minutes
3. Calcutta is east of Munich, therefore the time is ahead. Thus 9.00 a.m. plus 5 hours and 40 minutes = 2.40 p.m.
There are many ways of determining the longitude of a place. The simplest way is to compare the local time with G.M.T. by listening to B.B.C. radio. For example, the captain of a ship in the midst of the ocean wants to find out in which longitude his ship lies. If G.M.T. is 8.00 a.m. and it is noon in the local region, it means that he is four hours ahead of Greenwish, and must be east of Greenwich. His longitude is 4 x 15 degrees or 60 degrees east.