A foreland basin is a structural basin that develops adjacent and parallel to a mountain belt. The width and depth of the basin is determined by the flexural rigidity of the underlying lithosphere. The foreland basin receives sediment that is eroded off the adjacent mountain belt, foreland basins represent an endmember basin type, the other being rift basins. Space for sediments is provided by loading and downflexure to form foreland basins, in contrast to rift basins, the wedge-top sits on top of the moving thrust sheets and contains all the sediments charging from the active tectonic thrust wedge. This is where piggyback basins form, the foredeep is the thickest sedimentary zone and thickens toward the orogen. Sediments are deposited via distal fluvial, deltaic, the forebulge and backbulge are the thinnest and most distal zones and are not always present. When present, they are defined by regional unconformities as well as aeolian, sedimentation is most rapid near the moving thrust sheet. Sediment transport within the foredeep is generally parallel to the strike of the thrust fault, the motion of the adjacent plates of the foreland basin can be determined by studying the active deformation zone with which it is connected.
Today GPS measurements provide the rate at which one plate is moving relative to another and it is important to consider that present day kinematics are unlikely to be the same as when deformation began. Thus, it is crucial to consider models to determine the long-term evolution of continental collisions. Comparing both modern GPS and non-GPS models allows deformation rates to be calculated, comparing these numbers to the geologic regime helps constrain the number of probable models as well as which model is more geologically accurate within a specific region. Seismicity determines where active zones of activity occur as well as measure the total fault displacements. Foreland basins form because as the mountain belt grows, it exerts a significant mass on the Earth’s crust and this occurs so that the weight of the mountain belt can be compensated by isostasy at the upflex of the forebulge. The plate tectonic evolution of a foreland basin involves three general stages. First, the passive margin stage with orogenic loading of previously stretched continental margin during the stages of convergence.
Second, the early convergence stage defined by water conditions. The temperature underneath the orogen is much higher and weakens the lithosphere, the thrust belt is mobile and the foreland basin system becomes deformed over time. Syntectonic unconformities demonstrate simultaneous subsidence and tectonic activity, foreland basins are filled with sediments which erode from the adjacent mountain belt
Baltica was a late-Proterozoic, early-Palaeozoic continent that now includes the East European craton of northwestern Eurasia. Baltica was created as an entity not earlier than 1.8 billion years ago, before this time, the three segments/continents that now compose the East European craton were in different places on the globe. Baltica existed on a plate called the Baltic Plate. ~1.82 billion years ago, Baltica was part of the major supercontinent Columbia, ~1.5 billion years ago, Baltica along with Arctica and East Antarctica were part of the minor supercontinent Nena. ~1.07 billion years ago, Baltica was part of the major supercontinent Rodinia, ~750 million years ago, Baltica was part of the minor supercontinent Protolaurasia. ~600 million years ago, Baltica was part of the major supercontinent Pannotia, ~Cambrian, Baltica was an independent continent. ~Late Ordovician, Baltica collided with Avalonia ~Devonian, Baltica collided against Laurentia, ~Permian, all major continents collided against each other to form the major supercontinent Pangaea.
~Jurassic, Pangaea rifted into two supercontinents and Gondwana. Baltica was part of the minor supercontinent Laurasia, ~Cretaceous, Baltica was part of the minor supercontinent Eurasia. ~Present, Baltica is part of the minor supercontinent Afro-Eurasia. Around 250 million years from now, all continents may crash together, Baltica would be part of Pangaea Proxima. Around 450-600 Ma from now, Pangea Proxima will eventually rift apart
Although geophysics was only recognized as a separate discipline in the 19th century, its origins date back to ancient times. The first magnetic compasses were made from lodestones, while more modern magnetic compasses played an important role in the history of navigation, the first seismic instrument was built in 132 BC. Geophysics is applied to societal needs, such as resources, mitigation of natural hazards. Geophysics is a highly interdisciplinary subject, and geophysicists contribute to area of the Earth sciences. To provide an idea of what constitutes geophysics, this section describes phenomena that are studied in physics and how they relate to the Earth. The gravitational pull of the Moon and Sun give rise to two high tides and two low tides every lunar day, or every 24 hours and 50 minutes, there is a gap of 12 hours and 25 minutes between every high tide and between every low tide. Gravitational forces make rocks press down on rocks, increasing their density as the depth increases.
Measurements of gravitational acceleration and gravitational potential at the Earths surface, the surface gravitational field provides information on the dynamics of tectonic plates. The geopotential surface called the geoid is one definition of the shape of the Earth, the geoid would be the global mean sea level if the oceans were in equilibrium and could be extended through the continents. The Earth is cooling, and the heat flow generates the Earths magnetic field through the geodynamo. The main sources of heat are the heat and radioactivity. Some heat is carried up from the bottom of the mantle by mantle plumes, the heat flow at the Earths surface is about 4.2 ×1013 W, and it is a potential source of geothermal energy. Seismic waves are vibrations that travel through the Earths interior or along its surface, the entire Earth can oscillate in forms that are called normal modes or free oscillations of the Earth. Ground motions from waves or normal modes are measured using seismographs, if the waves come from a localized source such as an earthquake or explosion, measurements at more than one location can be used to locate the source.
The locations of earthquakes provide information on plate tectonics and mantle convection, measurements of seismic waves are a source of information on the region that the waves travel through. If the density or composition of the rock changes suddenly, some waves are reflected, reflections can provide information on near-surface structure. Changes in the direction, called refraction, can be used to infer the deep structure of the Earth. Earthquakes pose a risk to humans, understanding their mechanisms, which depend on the type of earthquake, can lead to better estimates of earthquake risk and improvements in earthquake engineering
A continent is one of several very large landmasses on Earth. Generally identified by convention rather than any strict criteria, up to seven regions are regarded as continents. Ordered from largest in size to smallest, they are, Africa, North America, South America, Europe, in geology, areas of continental crust include regions covered with water. Islands are frequently grouped with a continent to divide all the worlds land into geopolitical regions. Under this scheme, most of the countries and territories in the Pacific Ocean are grouped together with the continent of Australia to form a geopolitical region called Oceania. By convention, continents are understood to be large, discrete masses of land, many of the seven most commonly recognized continents identified by convention are not discrete landmasses separated completely by water. Earths major landmasses all have coasts on a single, continuous World Ocean, the most restricted meaning of continent is that of a continuous area of land or mainland, with the coastline and any land boundaries forming the edge of the continent.
From this perspective the edge of the shelf is the true edge of the continent. In this sense the islands of Great Britain and Ireland are part of Europe, while Australia, as a cultural construct, the concept of a continent may go beyond the continental shelf to include oceanic islands and continental fragments. In this way, Iceland is considered part of Europe and Madagascar part of Africa, extrapolating the concept to its extreme, some geographers group the Australasian continental plate with other islands in the Pacific into one continent called Oceania. This divides the land surface of Earth into continents or quasi-continents. The ideal criterion that each continent be a discrete landmass is commonly relaxed due to historical conventions, of the seven most globally recognized continents, only Antarctica and Australia are completely separated from other continents by ocean. Several continents are defined not as absolutely distinct bodies but as more or less discrete masses of land and Africa are joined by the Isthmus of Suez, and North and South America by the Isthmus of Panama.
In both cases, there is no separation of these landmasses by water. Both these isthmuses are very narrow compared to the bulk off the landmasses they unite, North America and South America are treated as separate continents in the seven-continent model. However, they may be viewed as a continent known as America or the Americas. This viewpoint was common in the United States until World War II and this remains the more common vision in Latin American countries, Portugal, France and Greece, where they are taught as a single continent. The criterion of a landmass is completely disregarded if the continuous landmass of Eurasia is classified as two separate continents and Asia
The Pleistocene is the geological epoch which lasted from about 2,588,000 to 11,700 years ago, spanning the worlds most recent period of repeated glaciations. The end of the Pleistocene corresponds with the end of the last glacial period, the Pleistocene is the first epoch of the Quaternary Period or sixth epoch of the Cenozoic Era. In the ICS timescale, the Pleistocene is divided into four stages or ages, all of these stages were defined in southern Europe. In addition to this subdivision, various regional subdivisions are often used. Charles Lyell introduced the term pleistocene in 1839 to describe strata in Sicily that had at least 70% of their molluscan fauna still living today and this distinguished it from the older Pliocene Epoch, which Lyell had originally thought to be the youngest fossil rock layer. The Pleistocene has been dated from 2.588 million to 11,700 years before present and it covers most of the latest period of repeated glaciation, up to and including the Younger Dryas cold spell.
The end of the Younger Dryas has been dated to about 9640 BC, the IUGS has yet to approve a type section, Global Boundary Stratotype Section and Point, for the upper Pleistocene/Holocene boundary. The proposed section is the North Greenland Ice Core Project ice core 75°06 N 42°18 W, the lower boundary of the Pleistocene Series is formally defined magnetostratigraphically as the base of the Matuyama chronozone, isotopic stage 103. Above this point there are notable extinctions of the calcareous nanofossils, Discoaster pentaradiatus, the Pleistocene covers the recent period of repeated glaciations. The name Plio-Pleistocene has, in the past, been used to mean the last ice age. The revised definition of the Quaternary, by pushing back the date of the Pleistocene to 2.58 Ma. Pleistocene climate was marked by repeated glacial cycles in which continental glaciers pushed to the 40th parallel in some places and it is estimated that, at maximum glacial extent, 30% of the Earths surface was covered by ice.
In addition, a zone of permafrost stretched southward from the edge of the sheet, a few hundred kilometres in North America. The mean annual temperature at the edge of the ice was −6 °C, during interglacial times, such as at present, drowned coastlines were common, mitigated by isostatic or other emergent motion of some regions. The effects of glaciation were global, antarctica was ice-bound throughout the Pleistocene as well as the preceding Pliocene. The Andes were covered in the south by the Patagonian ice cap, there were glaciers in New Zealand and Tasmania. The current decaying glaciers of Mount Kenya, Mount Kilimanjaro, glaciers existed in the mountains of Ethiopia and to the west in the Atlas mountains. In the northern hemisphere, many glaciers fused into one, the Cordilleran ice sheet covered the North American northwest, the east was covered by the Laurentide
Finland, officially the Republic of Finland, is a sovereign state in Northern Europe. A peninsula with the Gulf of Finland to the south and the Gulf of Bothnia to the west, the country has borders with Sweden to the northwest, Norway to the north. Estonia is south of the country across the Gulf of Finland, Finland is a Nordic country situated in the geographical region of Fennoscandia, which includes Scandinavia. Finlands population is 5.5 million, and the majority of the population is concentrated in the southern region,88. 7% of the population is Finnish people who speak Finnish, a Uralic language unrelated to the Scandinavian languages, the second major group are the Finland-Swedes. In terms of area, it is the eighth largest country in Europe, Finland is a parliamentary republic with a central government based in the capital Helsinki, local governments in 311 municipalities, and an autonomous region, the Åland Islands. Over 1.4 million people live in the Greater Helsinki metropolitan area, from the late 12th century, Finland was an integral part of Sweden, a legacy reflected in the prevalence of the Swedish language and its official status.
In the spirit of the notion of Adolf Ivar Arwidsson, we are not Swedes, we do not want to become Russians, let us therefore be Finns, nevertheless, in 1809, Finland was incorporated into the Russian Empire as the autonomous Grand Duchy of Finland. In 1906, Finland became the nation in the world to give the right to vote to all adult citizens. Following the 1917 Russian Revolution, Finland declared itself independent, in 1918, the fledgling state was divided by civil war, with the Bolshevik-leaning Reds supported by the equally new Soviet Russia, fighting the Whites, supported by the German Empire. After a brief attempt to establish a kingdom, the became a republic. During World War II, the Soviet Union sought repeatedly to occupy Finland, with Finland losing parts of Karelia and Kuusamo, Petsamo and some islands, Finland joined the United Nations in 1955 and established an official policy of neutrality. The Finno-Soviet Treaty of 1948 gave the Soviet Union some leverage in Finnish domestic politics during the Cold War era, Finland was a relative latecomer to industrialization, remaining a largely agrarian country until the 1950s.
It rapidly developed an advanced economy while building an extensive Nordic-style welfare state, resulting in widespread prosperity, Finnish GDP growth has been negative in 2012–2014, with a preceding nadir of −8% in 2009. Finland is a top performer in numerous metrics of national performance, including education, economic competitiveness, civil liberties, quality of life, a large majority of Finns are members of the Evangelical Lutheran Church, though freedom of religion is guaranteed under the Finnish Constitution. The first known appearance of the name Finland is thought to be on three rune-stones. Two were found in the Swedish province of Uppland and have the inscription finlonti, the third was found in Gotland, in the Baltic Sea. It has the inscription finlandi and dates from the 13th century, the name can be assumed to be related to the tribe name Finns, which is mentioned first known time AD98. The name Suomi has uncertain origins, but a candidate for a source is the Proto-Baltic word *źemē, in addition to the close relatives of Finnish, this name is used in the Baltic languages Latvian and Lithuanian
The sub-Cambrian peneplain is a geomorphic unit covering large swathes of Fennoscandia. It consists in a series of low relief zones that are at some locations covered by sedimentary rock dating to the Cambrian. Close to the rocks the exposed parts of the peneplain are extraordinarily flat. The Sub-Cambrian peneplain extends as an almost continuous belt along the eastern coast of Sweden for some 700 km from north to south, near Stockholm and Hudiksvall the peneplain is densely dissected by joint valleys and at the High Coast is the Sub-Cambrian penepain is both highly uplifted and eroded. To the east the Sub-Cambrian peneplain continues as an unconformity beneath the East European Platform, the island Blå Jungfrun in the Baltic Sea is an ancient inselberg belonging to the Sub-Cambrian peneplain. Being a inselberg formed in Precambrian time it was buried in sandstone after its formation, in the central Swedish lowlands the peneplain extends further west being 450 km wide from west to east. Further west parts of the Paleic surface in Norway have been interpreted to be part of the peneplain that has been uplifted and is apparently disrupted by NNE-SSW trending faults.
The 1,100 m high Hardangervidda plateau in Norway is an example of a thought to be a uplifted remnant of the peneplain. Interpretations of Jotnian sandstone imply that much of the Baltic Shield have had faint relief since the Mesoproterozoic, the peneplain formed after 600 million years ago but prior to the Cambrian trangression. The basement rocks forming the surface were exhumed from depths were the temperature was in excess of 100° C prior to the formation of peneplain. Karna Lidmar-Bergström and co-workers assume the peneplain formed though a cycle of erosion with a preceding valley phase, the flatness of the peneplain meant that during the Cambrian transgression very large areas were swiftly flooded forming large and shallow inland seas in evolving configurations. The new relief formed on top of Cambrian sediments smoothed out irregularities in the peneplain, Baltic Klint Muddus plains Norrland terrain South Småland peneplain
Composed of igneous rock resulting from its long volcanic history, the area is covered by a thin layer of soil. Human population is sparse, and industrial development is minimal, while mining is prevalent, the Canadian Shield is a physiographic division, consisting of five smaller, physiographic provinces, the Laurentian Upland, Kazan Region, Davis and James. The shield extends into the United States as the Adirondack Mountains, the Canadian Shield is U-shaped and is a subsection of the Laurentia craton signifying the area of greatest glacial impact creating the thin soils. The Canadian Shield is more than 3.96 billion years old, the Canadian Shield once had jagged peaks, higher than any of todays mountains, but millions of years of erosion have changed these mountains to rolling hills. The Canadian Shield was the first part of North America to be elevated above sea level and has remained almost wholly untouched by successive encroachments of the sea upon the continent. It is the Earths greatest area of exposed Archean rock, the metamorphic base rocks are mostly from the Precambrian Supereon, and have been repeatedly uplifted and eroded.
Today it consists largely of an area of low relief 300 to 610 m above sea level with a few monadnocks, during the Pleistocene Epoch, continental ice sheets depressed the land surface, scooped out thousands of lake basins, and carried away much of the regions soil. When the Greenland section is included, the Shield is approximately circular, bounded on the northeast by the northeast edge of Greenland and it covers much of Greenland, most of Quebec north of the St. In total, the area of the Shield covers approximately 8,000,000 km2. The underlying rock structure includes Hudson Bay, the Canadian Shield is among the oldest on earth, with regions dating from 2.5 to 4.2 billion years. The multitude of rivers and lakes in the region is caused by the watersheds of the area being so young. It has some of the oldest volcanoes on the planet and it has over 150 volcanic belts whose bedrock ranges from 600 to 1200 million years old. Each belt probably grew by the coalescence of accumulations erupted from numerous vents, many of Canadas major ore deposits are associated with Precambrian volcanoes.
The Sturgeon Lake Caldera in Kenora District, Ontario, is one of the worlds best preserved mineralized Neoarchean caldera complexes, the Canadian Shield contains the Mackenzie dike swarm, which is the largest dike swarm known on Earth. Mountains have deep roots and float on the denser mantle much like an iceberg at sea, as mountains erode, their roots rise and are eroded in turn. The rocks that now form the surface of the Shield were once far below the Earths surface, the high pressures and temperatures at those depths provided ideal conditions for mineralization. Although these mountains are now eroded, many large mountains still exist in Canadas far north called the Arctic Cordillera. This is a vast deeply dissected mountain range, stretching from northernmost Ellesmere Island to the northernmost tip of Labrador, the ranges highest peak is Nunavuts Barbeau Peak at 2,616 metres above sea level
The Scandinavian Mountains or the Scandes is a mountain range that runs through the Scandinavian Peninsula. The Scandinavian Mountains are often thought to be equivalent to the Scandinavian Caledonides. The western sides of the mountains drop precipitously into the North Sea and Norwegian Sea, forming the fjords of Norway, to the north they form the border between Norway and Sweden, still reaching 2,000 m high at the Arctic Circle. The mountain range just touches northwesternmost Finland, but are more than hills at their northernmost extension at the North Cape. The combination of a location and moisture from the North Atlantic Ocean has caused the formation of many ice fields. In Northern Norway, permafrost becomes common from about 800 to 900 meters AMSL on the western slope, the Scandinavian Montane Birch forest and grasslands terrestrial ecoregion is closely associated with the mountain range. Its names in the Scandinavian languages are, in Swedish Skandinaviska fjällkedjan, Skanderna, Fjällen or Kölen, the names Kölen and Kjølen are often preferentially used for the northern part, where the mountains form a narrow range near the border region of Norway and Sweden.
In southern Norway there is a scatter of mountain regions with individual names, such as Dovrefjell, Jotunheimen. The mountain chains highest summits are mostly concentrated in an area between Stavanger and Trondheim in southern Norway, with peaks over 1300 m and some peaks over 2000 m. Around Trondheim Fjord peaks decrease in altitude to about 400–500 m rising again to heights in excess of 1900 m further north in Swedish Lapland, the southern part of the mountain range contains the highest mountain of Northern Europe, Galdhøpiggen at almost 2500 m. This part of the chain is broader and contains a series of plateaux. In south-western Norway the plateaux and gently undulating surfaces are strongly dissected by fjords, the mountain chain is present in Sweden from northern Dalarna northwards, south of this point the Scandinavian Mountains lie completely within Norway. Most of the Scandinavian Mountains lack alpine topography, and where it does have it does relate to altitude, to the east the Scandinavian Mountains proper bounds with mountains that are lower and less dissected and are known as the förfjäll.
Generally the förfjäll do not surpass 1000 m. a. s. l, as a geomorphic unit the förfjäll extends across Sweden as a 650 km long and 40 to 80 km broad belt from Dalarna in the south to Norrbotten in the north. The origin of mountain topography is debated by geologists. In Scandinavia the Caledonian Mountains begun a post-orogenic collapse in the Devonian implying tectonic extension, despite occurring in about the same area the ancient Caledonian Mountains and the modern Scandinavian Mountains are unrelated. The Scandinavian Mountains attained its height by tectonic processes different from orogeny, a two-stage model of uplift has been proposed for the Scandinavian Mountains in southern Norway. A first stage in the Mesozoic and a stage starting from the Oligocene
Gold is a chemical element with symbol Au and atomic number 79. In its purest form, it is a bright, slightly yellow, soft, malleable. Chemically, gold is a metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions, Gold often occurs in free elemental form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the element silver and naturally alloyed with copper. Less commonly, it occurs in minerals as gold compounds, often with tellurium, golds atomic number of 79 makes it one of the higher numbered, naturally occurring elements. It is thought to have produced in supernova nucleosynthesis, from the collision of neutron stars. Because the Earth was molten when it was formed, almost all of the present in the early Earth probably sank into the planetary core. Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of acid and hydrochloric acid. Gold dissolves in solutions of cyanide, which are used in mining and electroplating.
Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction, as a precious metal, gold has been used for coinage and other arts throughout recorded history. A total of 186,700 tonnes of gold is in existence above ground, the world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry. Gold is used in infrared shielding, colored-glass production, gold leafing, certain gold salts are still used as anti-inflammatories in medicine. As of 2014, the worlds largest gold producer by far was China with 450 tonnes, Gold is cognate with similar words in many Germanic languages, deriving via Proto-Germanic *gulþą from Proto-Indo-European *ǵʰelh₃-. The symbol Au is from the Latin, the Latin word for gold, the Proto-Indo-European ancestor of aurum was *h₂é-h₂us-o-, meaning glow. This word is derived from the root as *h₂éu̯sōs, the ancestor of the Latin word Aurora. This etymological relationship is presumably behind the frequent claim in scientific publications that aurum meant shining dawn, Gold is the most malleable of all metals, a single gram can be beaten into a sheet of 1 square meter, and an avoirdupois ounce into 300 square feet.
Gold leaf can be thin enough to become semi-transparent
The Devonian is a geologic period and system of the Paleozoic, spanning 60 million years from the end of the Silurian,419.2 million years ago, to the beginning of the Carboniferous,358.9 Mya. It is named after Devon, where rocks from this period were first studied, the first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents, by the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. Various terrestrial arthropods became well-established, Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fish. The first ray-finned and lobe-finned bony fish appeared, while the placodermi began dominating almost every aquatic environment. The ancestors of all four-limbed vertebrates began adapting to walking on land, as their strong pectoral, in the oceans, primitive sharks became more numerous than in the Silurian and Late Ordovician.
The first ammonites, species of molluscs, trilobites, the mollusk-like brachiopods and the great coral reefs, were still common. The Late Devonian extinction which started about 375 million years ago severely affected marine life, killing off all placodermi, and all trilobites, save for a few species of the order Proetida. The palaeogeography was dominated by the supercontinent of Gondwana to the south, the continent of Siberia to the north, while the rock beds that define the start and end of the Devonian period are well identified, the exact dates are uncertain. According to the International Commission on Stratigraphy, the Devonian extends from the end of the Silurian 419.2 Mya, another common term is Age of the Fishes, referring to the evolution of several major groups of fish that took place during the period. Older literature on the Anglo-Welsh basin divides it into the Downtonian, Dittonian and Farlovian stages, in the Late Devonian, by contrast, arid conditions were less prevalent across the world and temperate climates were more common.
The Devonian Period is formally broken into Early and Late subdivisions, the rocks corresponding to those epochs are referred to as belonging to the Lower and Upper parts of the Devonian System. Early Devonian The Early Devonian lasted from 419.2 ±2.8 to 393.3 ±2.5 and began with the Lochkovian stage, which lasted until the Pragian. It spanned from 410.8 ±2.8 to 407.6 ±2.5, and was followed by the Emsian, which lasted until the Middle Devonian began,393. 3±2.7 million years ago. Middle Devonian The Middle Devonian comprised two subdivisions, first the Eifelian, which gave way to the Givetian 387. 7±2.7 million years ago. Late Devonian Finally, the Late Devonian started with the Frasnian,382.7 ±2.8 to 372.2 ±2.5, during which the first forests took shape on land. The first tetrapods appeared in the record in the ensuing Famennian subdivision. This lasted until the end of the Devonian,358. 9±2.5 million years ago, the Devonian was a relatively warm period, and probably lacked any glaciers
Western Australia is a state occupying the entire western third of Australia. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Southern Ocean to the south, the state has about 2.6 million inhabitants, around 11% of the national total. 92% of the lives in the south-west corner of the state. The first European visitor to Western Australia was the Dutch explorer Dirk Hartog, the first European settlement of Western Australia occurred following the landing by Major Edmund Lockyer on 26 December 1826 of an expedition on behalf of the New South Wales colonial government. This was followed by the establishment of the Swan River Colony in 1829, including the site of the present-day capital, york was the first inland settlement in Western Australia. Situated 97 kilometres east of Perth, it was settled on 16 September 1831, Western Australia achieved responsible government in 1890, and federated with the other British colonies in Australia in 1901. Today its economy relies on mining and tourism.
The state produces 46% of Australias exports, Western Australia is the second-largest iron ore producer in the world. The International Hydrographic Organization designates the body of water south of the continent as part of the Indian Ocean, the total length of the states eastern border is 1,862 km. There are 20,781 km of coastline, including 7,892 km of island coastline, the total land area occupied by the state is 2.5 million km2. Most of the state is a low plateau with an elevation of about 400 metres, very low relief. This descends relatively sharply to the plains, in some cases forming a sharp escarpment. The extreme age of the landscape has meant that the soils are remarkably infertile, even soils derived from granitic bedrock contain an order of magnitude less available phosphorus and only half as much nitrogen as soils in comparable climates in other continents. Soils derived from extensive sandplains or ironstone are even less fertile, nearly devoid of soluble phosphate and deficient in zinc, molybdenum, the infertility of most of the soils has required heavy application by farmers of chemical fertilisers, particularly superphosphate and herbicides.
These have resulted in damage to invertebrate and bacterial populations, the grazing and use of hoofed mammals and, heavy machinery through the years have resulted in compaction of soils and great damage to the fragile soils. Large-scale land clearing for agriculture has damaged habitats for native flora, large areas of the states wheatbelt region have problems with dryland salinity and the loss of fresh water. The southwest coastal area has a Mediterranean climate and it was originally heavily forested, including large stands of karri, one of the tallest trees in the world. This agricultural region is one of the nine most bio-diverse terrestrial habitats, thanks to the offshore Leeuwin Current, the area is one of the top six regions for marine biodiversity and contains the most southerly coral reefs in the world