Lecture 7 Minerals And Rocks 5 Flashcards
Sedimentary Rocks can be classified into what 2 categories?
Detrital Sedimentary Rock
Chemical Sedimentary Rock
What are detrital sedimentary rock: How do they form?
-Can consist of organic/inorganic materials
-Form from eroded/weathered rock fragments, smaller rocks, sediments/unconsolidated materials, organic materials
-They are just a bunch of ingredients referred to as detritus, mix of stuff that used to be
Detrital sedimentary rock can consist of what types of materials (2)
Organic and inorganic
What are inorganic detrital sedimentary rocks?
Rocks consisting of broken up pieces of other rocks and/or sediment/unconsolidated materials that have undergone lithification (compaction + cémentation)
What kind of rocks are inorganic detrital sedimentary rocks referred to as? What are they?
Clastic Rocks. They are rocks composed of broken pieces of other rocks and/or sediment/unconsolidated materials bonded tgt through lithification
What are detrital sedimentary rocks formed from?
Eroded/weathered rock fragments, smaller rocks, sediments/unconsolidated materials, organic materials
Detritus is latin for what?
Worn down
Inorganic Detrital Sedimentary Rocks include:
-Conglomerate
-Breccia
-Sandstone
-Siltstone
-Shale
What are chemical sedimentary rocks? How are they formed
-Rocks formed by precipitation of minerals from water
-Rocks consisting of components that originated as molecules/ions in water
True or false: Chemical sedimentary rocks can also contain fragments of organisms
True
What are three ions that often make their way into chemical sedimentary rocks?
Calcium ions, magnesium ions, carbonate ions, bicarbonate ions, sulfate ions.
True or False: Molecules/ions can stay in water for thousands/million of years and travel thousands of kilometres before finally forming mineral crystals and rocks.
True
What are chemical sedimentary rocks
Rocks formed by precipitation of minerals from water consisting of components that originated as molecules/ions
Can chemical sedimentary rocks contain fragments of organisms
Yes
Limestone is made primarily of what
Calcite (calcium carbonate)
Where does calcite in limestone originate from
Shells/hard parts of aquatic creatures
Can limestone be fossils or organisms that have become glued together
Yes
What is fossilferous limestone made of. Why is it distinct
Calcite like all limestone
Distinct in that it contains abundant fossils such as shells, coral and other marine organisms
What is coquina?
A rare form of limestone
Composed of shell fragments of mollusks and other marine invertebrates
Fragments glued together by calcite (CaCO3) that originated in these same shells
What is chalk? What’s it made of and what kind of rock is it. How is it formed
Chalk is made primarily of calcite (CaCO3) like all limestone
IT is a soft, white limestone with many pores
It is formed under sea/ocean/water by compression of plankton
What is plankton?
It includes a wide variety of plants and animals
Where does the word plankton come from and what does it mean
Comes from Greek word plankton which means drifter
What really is plankton
An organism is considered plankton if it is carried by tides and/or water’s currents and not able to move against these forces on its own
True or false: when something is plankton it will always stay plankton
False. Some organisms are plankton when young but eventually grow strong enough to swim against tides/currents.