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Philippe Cousteau
Philippe Cousteau, also known as Philippe Pierre Cousteau, is an American ocean advocate and television producer born in 1980, son of Philippe Cousteau Sr. and grandson of Jacques-Yves Cousteau, who co-founded EarthEcho International.
Philippine Sea Plate
The Philippine Sea Plate is a small, mostly submerged oceanic tectonic plate beneath the Philippine Sea between Japan, the Mariana Islands, Indonesia, and the Philippines, bounded almost entirely by subduction zones.
Phlegraean Fields
The Phlegraean Fields (Campi Flegrei) is a large active volcanic caldera west of Naples, Italy, where about 400,000 people live amid ongoing ground uplift and earthquakes.
Phlogopite
Phlogopite is a magnesium-rich mica mineral, typically brown, that forms the magnesium end-member of the biotite series and, with muscovite, is one of only two commercially used micas.
Phoslock
Phoslock is a lanthanum-modified bentonite clay, about 95% bentonite and 5% lanthanum, that binds phosphorus in lakes and reservoirs to control eutrophication and cyanobacterial blooms.
Phosphate minerals
Phosphate minerals are naturally occurring crystalline compounds built around the phosphate anion, forming a major mineral class dominated by apatite and supplying nearly all phosphorus used in fertilizers.
Phosphogenesis
Phosphogenesis is the formation of authigenic phosphate minerals, chiefly carbonate fluorapatite (francolite), in marine sediments, producing phosphorite, a rock with over 18 percent P2O5, mostly in coastal upwelling zones.
Phosphorus limitation
Phosphorus limitation is the control of biological production by phosphorus supply, the principle that phosphorus, not nitrogen or carbon, governs algal blooms and eutrophication in lakes.
Phosphorus loading
Phosphorus loading is the quantity of phosphorus delivered to a water body per unit time, either from the watershed and atmosphere or released from lake sediments.
Phosphorus sorption
Phosphorus sorption is the attachment of dissolved phosphate to sediment and soil particle surfaces, a process that buffers phosphorus concentrations in streams, lakes, and estuaries and drives eutrophication.
Photogeology
Photogeology is the study and interpretation of aerial photographs, normally vertical, to obtain geologic information and present it as mosaics, geologic maps, and cross sections.
Phyllite
Phyllite is a fine-grained, foliated metamorphic rock intermediate in grade between slate and schist, whose tiny mica crystals give its cleavage surfaces a silky sheen.
Physical climate risk
Physical climate risk is the financial risk from climate hazards such as extreme weather and sea level rise reducing the value of assets like real estate.
Physical geography
Physical geography, also known as physiogeography, is the branch of geography that studies Earth's natural environment and the processes shaping its surface, including landforms, climate, vegetation, soils, and hydrology.
Piacenzian
The Piacenzian is the youngest stage of the Pliocene Series and last age of the Neogene Period, spanning 3.6 to 2.58 million years ago, named after Piacenza, Italy.
Piceance Basin
The Piceance Basin is a structural and sedimentary basin in northwestern Colorado, named for Piceance Creek and holding the world's largest known oil shale deposit, about 1.53 trillion barrels.
Pierre Shale
The Pierre Shale is a Late Cretaceous marine shale formation of the northern Great Plains, named in 1862 from exposures at old Fort Pierre, South Dakota.
Piers Corbyn
Piers Corbyn (born 1947) is a British weather forecaster and astrophysicist who founded WeatherAction, a London company selling long-range forecasts based on solar activity and the Moon.
Piezometer
A piezometer is an instrument or well that measures groundwater pressure at a specific point in the subsurface, commonly used to monitor seepage in dams.
Pigeonite
Pigeonite is a calcium-poor clinopyroxene mineral of magnesium, iron, and calcium, named in 1900 for Pigeon Point, Minnesota, and typical of rapidly cooled basaltic lavas.
Pilbara Minerals
Pilbara Minerals, since renamed PLS Group Limited, is an Australian lithium mining company whose Pilgangoora Operation in Western Australia supplies about 8 per cent of world lithium.
Pillow lava
Pillow lava is fluid, usually basaltic lava that chills in contact with water and solidifies as rounded, pillow-shaped masses with glassy skins, forming most new ocean floor.
Pineapple Express
The Pineapple Express is an atmospheric river carrying tropical moisture from near Hawaii to the west coast of North America, bringing heavy rain and snow.
Piney Woods
The Piney Woods, also called the South Central Plains, is a temperate pine forest ecoregion covering East Texas, southern Arkansas, western Louisiana, and southeastern Oklahoma, and Texas's wettest natural region.
Pingualuit crater
Pingualuit crater, also known as Chubb Crater, is a meteorite impact crater in Ungava, northern Quebec, formed about 1.4 million years ago and filled by exceptionally pure Pingualuk Lake.
Pinos Altos mine
The Pinos Altos mine is a gold mine in the Sierra Madre of northern Chihuahua, Mexico, owned by Agnico Eagle, producing gold with by-product silver since 2008.
Pioch-Farrus
Pioch-Farrus (Pioch Farrus), ancient copper mine at Cabrières, Hérault, France, in the Cabrières-Péret district, the oldest known copper mines in France; Chalcolithic radiocarbon date 4310 ± 75 BP, firesetting confirmed, Gallo-Roman and later reuse.
Piri Reis
Piri Reis, born Ahmed Muhiddin Piri, was an Ottoman admiral and cartographer of the 1500s, best known for his 1513 world map and his sailing guide, the Kitab-ı Bahriye.
Pityusa Patera
Pityusa Patera, a large volcanic depression in Malea Planum, southern Mars near Hellas basin; IAU diameter 196.51 km, formed 3.9–3.8 Ga; interpreted as a giant caldera above a crust-mantle-boundary magma chamber.
Placer mining
Placer mining extracts valuable minerals, mostly gold, from loose sediment like stream gravel and beach sand using water and gravity, supplying two-thirds of the world's gold.