Presentation on theme: "97,3% of Hungary is covered with some kind of sediment 75% of land surface on the earth is covered by thin veneer of sediments or sedimentary rocks. Classification."— Presentation transcript:
97,3% of Hungary is covered with some kind of sediment 75% of land surface on the earth is covered by thin veneer of sediments or sedimentary rocks. Classification Based on the processes responsible for their formation, sedimentary rocks can be subdivided into three groups: clastic sedimentary rocks biochemical (or biogenic) sedimentary rocks chemical sedimentary rocks
Clastic sedimentary rocks are composed of silicate minerals and rock fragments that were transported by moving fluids (as bed load, suspended load, or by sediment gravity flows) and were deposited when these fluids came to rest.
Clastic sediment, and thus clastic sedimentary rocks, are subdivided according to the dominant particle size (diameter) and cementation Not cemented sediments Gravel (>2 mm) Sand (2 – 0,06 mm) Mud, kőzetliszt (0,06 - 0,002 mm Clay (<0,002 mm)
Water uptake of the clay deppand on the clay mineral compositon Water uptake → swelling Montmorillonite up tu 300 % volumetric swelling
Breccias are coarse grained rocks dominantly composed of gravel sized particles that are typically held together by a finer grained martix. The gravel sized particles are angular. Usage: deppands on the cementation: good quality: Masonary bricks, load bearing structures, ornamental stone
Conglomerates The gravel sized particles that make up conglomerates are well rounded Usage: deppands on the cementation: good quality: Masonary bricks, load bearing structures, ornamental stone
Sandstone (2 - 0,063 mm) Sandstones are medium grained rocks composed of rounded or angular fragments of sand size, that often but not always have a cement uniting them together. Usage: deppands on the cementation: good quality: Masonary bricks, load bearing structures, ornamental stone
Siltstone As its name implies, it is primarily composed (greater than 2/3) of silt sized particles, defined as grains 2–62 µm Usage: cheramic industry, insulations (water)
Loess predominantly silt-sized sediment, which is formed by the accumulation of wind-blown dust. Typically yellow. Slump is a tipical problam: volume due to saturation. Usege: cement industry
Claystone composed primarily of clay-sized particles (less than 1/256 millimeter in diameter). Usage: brick production Related to radioactive waste repositories, typical host rock
Biochemical rock Saturation of the solution - precipitate - Compaction – Cementation Limestone CaCO 3 (HCl solve it - fizz) Dense Limestone Course limestone Freshwater Limestone
VEGYI/BIOGÉN ÜLEDÉKES KŐZETEK Oldat kialakulása – Oldat telítődése – Kicsapódás, kiválás – Tömörödés – Diagenezis és cementáció Dolostone or dolomite rock is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite. CaMg(C0 3 ) 2 Can either contain bedded layers or be unbedded. It is less soluble than limestone in weakly acidic groundwater, but it can still develop solution features over time. Dolostone can act as an oil and natural gas reservoir. Usually fractured, hard to process (difficult to form bricks), it is brittle. Used as bulk material: ballast under road, rail ; concrete agregate White in the vicinity of natural fractures (Mg)
Biochemical sedimentary rocks Coal: usually occurring in rock strata in layers or veins called coal beds or coal seams: Peat, an accumulation of partially decayed vegetation or organic matter. considered to be a precursor of coal, has industrial importance as a fuel in some regions Lignite, or brown coal, is the lowest rank of coal and used almost exclusively as fuel for electric power generation. Bituminous coal is a dense sedimentary rock, usually black, but sometimes dark brown, fuel in steam-electric power generation, Anthracite, the highest rank of coal, is a harder, glossy black coal used primarily for residential and commercial space heating.
Other Sedimentary rocks Marl or marlstone is a calcium carbonate or lime-rich mud or mudstone which contains variable amounts of clays and silt. The dominant carbonate mineral in most marls is calcite, but other carbonate minerals such as aragonite, dolomite, and siderite may be present. his finely bedded material Usage.: cement industry, non-load bearing structures, typicaly highly fractured, it can be only used as bulk material. Bauxite, an aluminium ore, is the world's main source of aluminium. Red, pink, water uptake can be high Usage: in paints, aluminium production, sandpaper.