1.
At high wind velocities silt- and clay-sized particles are carried as bed load.
2.
Grain roundness is therefore a characteristic that can easily be seen in hand specimen using a hand lens, or will be evident under the microscope if a thin-section is cut of an aeolian sandstone
3.
A lagoon is the marine-influenced portion of a drowned valley.
4.
Sediment supply to the estuary is from river sources only and the processes that transport and deposit this sediment are a combination of river and wave and/or tidal processes.
5.
Difference between estuary and delta is that a delta retrograde inwards into the lake or sea. A estuary all the sedimentation occurs in the drowned valley
6.
An estuary developed in an area with a large tidal range and weak wave energy will typically have three divisions.
7.
Bay head delta: Is the zone where fluvial processes are dominant
8.
An estuary is a body of salt water separated from the deeper sea by a shallow or exposed barrier beach, sandbank, coral reef, or similar feature.
9.
The Bernoulli effect can best be explained by considering flow of a fluid (air, water or any fluid medium) in a tube that is narrower at one end than the other
10.
In cross-section wave ripples are generally symmetrical in profile, laminae within each ripple dip in both directions and are overlapping.
11.
Wave ripples are formed only in relatively shallow water in the absence of strong currents, whereas current ripples may form as a result of water flow in any depth in any subaqueous environment.
12.
Lavas are found close to the site of the eruption, but ash may be spread tens, hundreds or even thousands of kilometres away.
13.
Basaltic magmas tend to form volcanoes that produce small volumes of lava, but large amounts of volcanic ash
14.
Volcanoes with more silicic magma are much more explosive, with large amounts of the molten rock being ejected from the volcano as particulate matter
15.
•Calcium carbonate (CaCO3) is the principal compound in limestones.
16.
There is a chemical difference between calcite and aragonite.
17.
Cherts are fine-grained siliceous sedimentary rocks made up of silt-sized interlocking quartz crystals (microquartz) and chalcedony, a form of silica which is made up of radiating fibres a few tens to hundreds of microns long.
18.
Sediments and sedimentary rocks with a high proportion of organic matter are termed carbonates because they are rich in carbon.
19.
Fusain: bright, shiny black coal that usually breaks cubically and mostly consists of woody tissue.
20.
Volcaniclastic sediments These are the products of volcanic eruptions or the result of the breakdown of volcanic rocks.
21.
If all the clasts are of the same material (all of granite, for example), the conglomerate is considered to be polymict
22.
Siltis a textural term to define the finest grade of clastic sedimentary particles, those less than 4 microns in diameter.
23.
When clay- and silt-sized particles are mixed in unknown proportions as the main constituents in unconsolidated sediment we would call this material shale.
24.
Feldspar is the most common mineral seen in silt deposits
25.
Montmorillonite minerals can not absorb water within their structure.