Carbonate Petrography

Carbonate petrography is the study of limestones, dolomites and associated deposits under optical or electron microscopes greatly enhances field studies or core observations and can provide a frame of reference for geochemical studies.

25 strangest Geologic Formations on Earth

The strangest formations on Earth.

What causes Earthquake?

Of these various reasons, faulting related to plate movements is by far the most significant. In other words, most earthquakes are due to slip on faults.

The Geologic Column

As stated earlier, no one locality on Earth provides a complete record of our planet’s history, because stratigraphic columns can contain unconformities. But by correlating rocks from locality to locality at millions of places around the world, geologists have pieced together a composite stratigraphic column, called the geologic column, that represents the entirety of Earth history.

Folds and Foliations

Geometry of Folds Imagine a carpet lying flat on the floor. Push on one end of the carpet, and it will wrinkle or contort into a series of wavelike curves. Stresses developed during mountain building can similarly warp or bend bedding and foliation (or other planar features) in rock. The result a curve in the shape of a rock layer is called a fold.

Sunday, 30 April 2017

Equipment for Geological Field Work

Following is a list of all equipment that is likely to be needed in the field:

1. Adhesive tape
2. Aerial photographs
3. Altimeter
4. Binoculars
5. Calculator
6. Camera, tripod, film, etc
7. Chemicals for staining rocks
8. Cold chisel
9. Color pencils
10. Colored tape or paint for marking localities
11. Brunton compass or other
12. Drawing Board
13. Erasers
14. Field case for maps and photographs
15. Field glasses
16. First aid kit
17. Flashlight
18. Gloves
19. Gold pan
20. Grain-size card
21. Geologists Hammer
22. Hand lens
23. Dilute Hydrochloric Acid
24. Ink, waterproof; black, brown, blue, red and green
25. Insect repellent
26. Jacob staff
27. Knapsack
28. Lettering set
29. Loose-leaf blinder
30. Magnet
31. Maps, topographic, geologic
32. Microscope
33. Mineral hardness set
34. Field notebooks
35. Paper, lined
36. Paper, quadrille
37. Paper, scratch
38. Pen, drop circle
39. Pen, holders
40. Pen, ruling
41. Pens, ballpoint
42. Pen, inkflow, for photographs
43. Pencils, 3B to 9H
44. Pencil pointer
45. Pick or mattock
46. Pocket knife
47. Protractors
48. Rain gears
49. Rangefinder, Camera
50. Reference library
51. Sample bags
52. Scale, plotting, 6 in.
53. Shovel
54. Stereo-graphic net
55. Tally counter
56. Tape, 6-ft
57. Tape, 100-ft
58. Triangles, drawing
59. Satellite phone
60. Watch

Estwing Hammer and Hand lens


A hammer with a pick or chisel end is used for cleaning exposures, for digging, for breaking rocks, and for trimming samples. Standard geologists hammer have heads weighing 1.5 to 2 lb (0.68 to 0.9 kg) and are adequate for most geologic work. A small sledge--- for example a 2 or 3 lb head on a 14-in. handle may be needed to collect fresh  samples of especially hard rocks.
While using hammer, it is important,
1. to wear safety goggles
2. not to strike heavy blows when people are nearby
3. never to strike one angular rock edges

A cold chisel maybe used with a hammer to split rocks parallel to bedding or foliation and to free fossils or specific mineral samples from unfoliated rocks.

A map holder must be large enough to carry 9*9 in. aerial photographs and should be made of masonite rather than metal( which in uncomfortable to carry) or plastic (which may break when cold).

A scale, used for measuring features or laying off distances on maps and photographs, should have fine, distinct graduation marks that are equivalent to even increments at the map scale used.

A protractor is used for plotting structural symbol maps and for measuring angles between structures in rocks.

A camera, for, photo-geologic interpretation, is an important equipment for geological field work and should be compact and strong. All 35 mm cameras have a great depth of focus than cameras with longer focal length and this is a decided advantage in photographing irregular outcrops at closer range.

Samples bags of cloth or plastic maybe obtained through most suppliers, or bags maybe of extra heavy paper, the variety often used as nail bags.

Hydrochloric acid will be needed and should be diluted just to the strength that causes effervescence of calcite but not dolomite (except when powdered).

Of the hand lenses, 10X and 14X lenses are used most widely. The depth of focus of the 14X lens, however, is only 0.8 mm, whereas that of 10X lens is 2.5 mm.
Good quality triplet lenses typically give excellent images. In testing a lens, and in all other viewing, the following are important:

1. Hold the sample so that the area being viewed is in full light --- in sunlight, if possible.
2. Hold the lens exactly at the distance of sharp focus, with its optical axis perpendicular to the surface being viewed
3. Bring the eye to the point where the eyelashes are mostly touching the lens (this is the only position from which the entire field of view will be sharply and comfortably in focus)


Saturday, 29 April 2017

3D Geological Model of Pakistan

We are GLAD to inform you that one of our admin, Muhammad Qasim Mehmood with his team have prepared a geological model which was presented at All Pakistan Science Fest hosted by UET Science Society at 20/04/17. 

Here is the brief introduction of model:

It is a 3D geological model of Pakistan that shows mainly tectonic division of mountain ranges of Pakistan. The model demonstrates the major/famous deposits of Pakistan like Petroleum, Minerals/Gemstones, Uranium, Coal including other geographical features like dams and rivers.

It is a non-working model (size: 5
×
6 ft approximately) supported mainly by wooden boards and other cementing material. It is using thermocol sheets, maps, large paper sheets, graphs, paints and mechanical and scientific goods as per the requirement of a particular model.

This unique model cover the topics of Plate Tectonics, Structural Geology, Economic Geology and others. Also the students have added the future aspects of Geo-economics like Kalabagh Dam, CPEC route, oil and gas wells in Baluchistan and offshore wells in Arabian Sea near Gwadar.


The model is showing the following geological aspects of Pakistan:

1. Major Geological Basins of Pakistan i.e. Indus Basin and Balochistan Basin
2. Major Thrusts in Northern Pakistan
     Main Karakoram Thrust (MKT)
     Main Mantle Thrust (MMT)
     Main Central Thrust (MCT)
     Main Boundary Thrust (MBT)
     Salt Range Thrust / Himalayan Frontal Thrust
3.  Mountain Ranges of Pakistan
     Some mountain ranges of Pakistan is shown on the model located in North-West to              South-West of Pakistan which has important geological significance in distinguishing            Indus Basin from Balochistan Basin
4.  Famous Peaks of Pakistan
     Mount Godwin-Austen (k2) - World's 2nd highest peak
     Nanga Parbat ( The Killer Mountain) - World's 9th highest peak
     Tirich Mir - highest peak in Hindukush Range

5. Major Fuel of Pakistan
     Oil wells in Potwar Plateau and in Balochistan
     Gas wells in Sui, Balochistan - biggest gas reserve in Pakistan
     Coal reserves in Thar - World's 16th largest coal reserve in Pakistan
     Uranium reserves in Siwalik Hills west of Dera Ghazi Khan
6. Famous Gem Stone of Pakistan
    Emerald from Mingora, Swat 
    Aquamarine from Hunza Valley,Gilgit-Baltistan    Tourmaline from Skardu District, Gilgit Baltistan

And two future prospects for the improvement of Geo-economics of Pakistan:
1. Kalabagh Dam (to be made)
2. China Pakistan Economic Corridor -CPEC (construction under process) western route.

Following are some of the maps (obtained from internet) which we consider during the preparing of our model

Map showing Geological Basins of Pakistan
Source: GSP

Tectonic Map of Pakistan
Source: GSP

Political Map of Pakistan
Source: Unknown
Tectonic Map of Pakistan & India showing major regional thrusts
Source: Unknown
CPEC map
Source: CPEC website
And some photos captured during the preparation of model

Cutting of thermocol sheet

coloring thermocol sheet with finishing paint

Hasan creating "finishing of paint" with paint spatula scraper

final look of Stage 1
Umer Amin sketching map on model and fixing sticks for projections and heights


sketches of mountain ranges and river tributaries and sticks for average height of each range and peak
all things are made perfect due to plotting of each point according to longitude and latitude


 a great Atlas Book

maps and maps


a rough look of model showing mountain ranges made with Plaster of Paris
Completion of Stage 2

team work!!!


after using distemper paint

And finally after painting and drawing river tributaries, fixing sign boards of cities and much more, the model is:

 3D Geological Model of Pakistan




 3D Geological Model of Pakistan


Legend for the model



Geological tools, Gemstones, Rocks and Fuel (Coal and Crude Oil)
Featuring Qasim Mehmood (Co founder of Learning Geology), on left
and
Rana Faizan Saleem, my class mate and CEO of Geology for Beginners
Students of Institute of Geology, University of the Punjab

Pyrope

What is Pyrope?

Pyrope is the most well-known gemstone form of Garnet. The term Garnet describes a group name for several closely related minerals that form important gemstones, and Pyrope is an individual member mineral of the Garnet group. Its dark, blood-red colour is distinct and attractive, and makes a fine Garnet gemstone. In the gem trade, the term Pyrope is rarely used on its own. It is either generically called "Garnet", or "Pyrope Garnet".
The mineral pyrope is a member of the garnet group. Pyrope is the only member of the garnet family to always display red colouration in natural samples, and it is from this characteristic that it gets its name: from the Greek for fire and eye. The composition of pure pyrope is Mg3Al2(SiO4)3, although typically other elements are present in at least minor proportions-these other elements include Ca, Cr, Fe and Mn. Pyrope forms a solid solution series with almandine and spessartine, which are collectively known as the pyralspite garnets (pyrope, almandine, spessartine). Iron and manganese substitute for the magnesium in the pyrope structure. The resultant, mixed composition garnets are defined according to their pyrope-almandine ratio. The semi-precious stone rhodolite is a garnet of ~70% pyrope composition.
The origin of most pyrope is in ultramafic rocks, typically peridotite from the Earth's mantle: these mantle-derived peridotites can be attributed both to igneous and metamorphic processes. Pyrope also occurs in ultrahigh-pressure (UHP) metamorphic rocks, as in the Dora-Maira massif in the western Alps. In that massif, nearly pure pyrope occurs in crystals to almost 12 cm in diameter; some of that pyrope has inclusions of coesite, and some has inclusions of enstatite and sapphirine.
Pyrope is common in peridotite xenoliths from kimberlite pipes, some of which are diamond-bearing. Pyrope found in association with diamond commonly has a Cr2O3 content of 3-8%, which imparts a distinctive violet to deep purple colouration (often with a greenish tinge) and because of this is often used as a kimberlite indicator mineral in areas where erosive activity makes pin pointing the origin of the pipe difficult. These varieties are known as chrome-pyrope, or G9/G10 garnets.

History and Introduction

Pyrope garnet is the best known of the red garnets. It has a distinctive red colour that often resembles the colour of ruby or pomegranate seeds. The word "pyrope" comes from the Greek word "puropus", made up of "pur" (fire) and "ops" (eye) meaning "fiery-eyed". This refers to the impressive brilliance of pyrope garnet, which is a result of its high refractive index.
The use of red garnet dates back thousands of years, when it was used by Egyptian pharaohs for both decorative and ceremonial purposes. The ancient Romans also wore garnet rings and traded garnet gemstones. In ancient times, garnet and other red gemstones cut en cabochon were called "carbuncles", which is not the prettiest of names because it was also used to define pus-filled boils. Nowadays, any natural red gemstone cabochon can be traded as carbuncle stones.
The Latin word, "carbunculus" alludes to a burning piece of coal or ember. This may have been used to refer to garnet because of its bright colour large deposits of pyrope garnet were discovered in Bohemia (Central Europe) around the 16th century, which became the focus of the jewellery industry in the area. Bohemian pyrope garnet from the Czech Republic continues to be mined today.

Identifying Pyrope Garnet

Pyrope garnet is magnesium aluminium garnet. Iron can substitute for the magnesium and become more like almandine, which is iron aluminium garnet. Pure pyrope and pure almandine are rare in nature and most specimens are a mixture of the two. The change in density from almandine (4.3) to pyrope (3.6) is the only good test to determine a specimen's likely identity. Garnet can be distinguished from other gem types by its occurrence in metamorphic rock, its hardness (6.5 - 7.5 on the Mohs scale), colour, refractive index and cubic crystal structure. However, the quickest way to identify garnet is with the use of strong neodymium magnets. Garnet is attracted to neodymium magnets because it contains high concentrations of iron and/or manganese.

Origin and Gemstone Sources

Pyrope garnet sources include China, Madagascar, Myanmar, South Africa, Sri Lanka, Tanzania and the United States. Deposits in the Czech Republic do still exist, but are of minor importance.

Determining Pyrope Garnet Gemstone Value

Pyrope Garnet Colour

The characteristic dark-red of pyrope garnet is found in small sized stones. Bigger gems tend to be very dark, coming close to black.

Pyrope Garnet Clarity and Luster

Pyrope garnet is often inclusion free, so buyers should seek an "eye clean" stone. Pyrope garnet has a beautiful glossy vitreous luster.

Pyrope Garnet Cut and Shape

Pyrope garnet is versatile and can be cut into a wide variety of shapes. Pyrope garnet is not often seen in large sizes. It can be faceted or cut en cabochon. Faceted cuts best exhibit the beauty of pyrope garnet.

Pyrope Garnet Treatment

Pyrope garnet is not known to be treated or enhanced in any way.

Pyrope Metaphysical and healing properties

Pyrope Garnet offer us physical, emotional and spiritual support. Use its healing powers to boost circulation and blood disorders, as well as the digestive tract and immune system. Pyrope emotionally relieves anxiety, and promotes composure, courage and endurance. It lightens the overall mood. It protects the Base and Crown Chakras, and may balance the Heart and Brow Chakras as well.
Pyrope Garnet stimulates warmth and gentleness, unifying the creative forces of the self. On the spiritual path, it also helps open the heart to love - from Divine Love, as well as love of others.
Pyrope Garnets range in colour energies from rose red to deep crimson, including shades of scarlet, amethyst and indigo. It attracts a host of Angels and honours four Goddesses.
Garnet is the traditional birthstone of January, and Pyrope, in various hues, is a natural birthstone for many born at the end of summer through the winter. It is the zodiac stone for those born under the sign of Aquarius and it brings you Fire energy. As an Enhancer Strengthener crystal, it is a talisman of protection.

Properties of Pyrope

Chemical FormulaMg3Al2Si3O12
ColourRed
Hardness7 - 7.5
Crystal SystemIsometric
Refractive Index1.720 - 1.760
SG3.5 - 3.6
TransparencyTransparent to translucent
Double RefractionNone
LusterVitreous
CleavageNone
Mineral ClassPyrope (Garnet)

Sunday, 23 April 2017

Geologic Contacts

A geologic contact is where one rock type touches another. There are three types of geologic contact:1. Depositional contacts are those where a sedimentary rock (or a lava flow) was deposited on an older rock
2. Intrusive contacts are those where one rock has intruded another
3. Fault contacts are those where rocks come into contact across fault zones.
Learn in detail about fault here

Following are the some pictures showing each type of geologic contact

Depositional Contacts

1. Angular Unconformity, Siccar Point, Scotland

This place is known as Siccar Point which is the most important unconformity described by James Hutton (1726-1797) in support of his world-changing ideas on the origin and age of the Earth.
Here 
gently sloping strata of 370-million-year-old Famennian Late Devonian Old Red Sandstone and a basal layer of conglomerate overlie near vertical layers of 435-million-year-old lower Silurian Llandovery Epoch greywacke, with an interval of around 65 million years.


2. Cretaceous Sandstone overlying Conglomerate    Kootenai Formation, SW Montana

Photo Courtesy: marlimillerphoto.com

3. Dun Briste Sea Stack, IrelandDun Briste is a truly incredible site to see but must be visited to appreciate its splendour. It was once joined to the mainland. The sea stack stands 45 metres (150 feet) tall.

Dun Briste and the surrounding cliffs were formed around 350 million years ago (during the 'Lower Carboniferous Period'), when sea temperatures were much higher and the coastline at a greater distance away.  There are many legends describing how the Sea Stack was formed but it is widely accepted that an arch leading to the rock collapsed during very rough sea conditions in 1393. This is remarkably recent in geological terms

Photo Courtesy: dunbriste.com 


Fault Contacts

1. Normal Faulting in the Cutler Formation near Arches National Park

Photo Courtesy: travelinggeologist.com

2. Normal Fault in Titus Canyon, Death Valley, California 

Photo Courtesy: travelinggeologist.com


3. 
Horst and Graben Structure in Zanjan, Iran

Photo Courtesy: Amazhda

Intrusive Contacts 

1. 
Pegmatite and aplite dikes and veins in granitic rocks on Kehoe Beach, Point Reyes National Seashore, California.


2. Spectacular mafic dyke from Isla de Socorro from Pep Cabré. The Isla de Socorro is a volcanic island off the west coast of Mexico and it is the only felsic volcano in the Pacific Ocean

Photo Courtesy: travelinggeologist.com

3. The margins of this Granite dyke cooled relatively quickly in contact with this much older Gabbro.
Photo near Ai-Ais Namibia

Photo Courtesy: travelinggeologist