Definition
Marl is an unconsolidated sedimentary rock consisting of clay and lime
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
History
Origin
-
-
Discoverer
William Smith
Johann Gottlob Lehmann
Etymology
From Old French marle, from Late Latin marglia
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Earthy
Clastic, Splintery
Color
Beige, Brown, Green, Grey, White
Black, Brown, Buff, Green, Grey, Red, Yellow
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Rough and Dull
Muddy
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, Roof Tiles
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Medical Industry
-
-
Antiquity Uses
Artifacts, Jewellery, Sculpture, Small Figurines
Artifacts, Sculpture
Other Uses
Commercial Uses
Creating Artwork, Soil Conditioner
Creating Artwork, Pottery
Types
Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Features
Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
Jantar Mantar in India
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
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-
Fossils
Present
Present
Formation
Marl forms when very fine-grained clay particles are deposited in water which settles at the bottom of water bodies and are compacted by overlying sediment; the water squeezes out and hence forming Marl rock.
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
Composition
Mineral Content
Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Ca, Fe, Mg, Silicon Dioxide, Sodium
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Physical Properties
Hardness
2-33
1
7
👆🏻
Grain Size
Very fine-grained
Very fine-grained
Fracture
Conchoidal
-
Streak
White
White
Porosity
Highly Porous
Highly Porous
Luster
Dull
Dull
Compressive Strength
30.00 N/mm295.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Slaty
Toughness
2.6
2.6
Specific Gravity
2.2-2.82.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm32.4-2.8 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.80 kJ/Kg K0.39 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
India, Pakistan, Russia
Bangladesh, China, India, Russia
Africa
Ethiopia, Kenya, Morocco, South Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Others
-
-
Deposits in Western Continents
North America
USA
USA
South America
Colombia, Ecuador, Peru
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Victoria, Western Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia