The Holocene is the current geological epoch. It began approximately 9,700 years before the Common Era (BCE). It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial.
A megatsunami is a very large wave created by a large, sudden displacement of material into a body of water.
A loess is a clastic, predominantly silt-sized sediment that is formed by the accumulation of wind-blown dust. Ten percent of Earth's land area is covered by loesses or similar deposits.
Longshore drift from longshore current is a geological process that consists of the transportation of sediments along a coast parallel to the shoreline, which is dependent on the angle of incoming wave direction. Oblique incoming wind squeezes water along the coast, and so generates a water current which moves parallel to the coast. Longshore drift is simply the sediment moved by the longshore current. This current and sediment movement occur within the surf zone. The process is also known as littoral drift.
A raised beach, coastal terrace, or perched coastline is a relatively flat, horizontal or gently inclined surface of marine origin, mostly an old abrasion platform which has been lifted out of the sphere of wave activity. Thus, it lies above or under the current sea level, depending on the time of its formation. It is bounded by a steeper ascending slope on the landward side and a steeper descending slope on the seaward side. Due to its generally flat shape, it is often used for anthropogenic structures such as settlements and infrastructure.
Carolina bays are elliptical to circular depressions concentrated along the East Coast of the United States within coastal New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, and north Florida. In Maryland, they are called Maryland basins. Within the Delmarva Peninsula, they and other coastal ponds are also called Delmarva bays.
Tollmann's bolide hypothesis is a hypothesis presented by Austrian palaeontologist Edith Kristan-Tollmann and geologist Alexander Tollmann in 1994. The hypothesis postulates that one or several bolides struck the Earth around 7640 ± 200 years BCE, and a much smaller one approximately 3150 ± 200 BCE. The hypothesis tries to explain early Holocene extinctions and possibly legends of the Universal Deluge.
Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth. Winds may erode, transport, and deposit materials and are effective agents in regions with sparse vegetation, a lack of soil moisture and a large supply of unconsolidated sediments. Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts.
The Black Sea deluge is the best known of three hypothetical flood scenarios proposed for the Late Quaternary history of the Black Sea. One other flood scenario proposes a rapid, even catastrophic, rise in sea level of the Black Sea.
The Fenambosy Chevron is one of four chevron-shaped land features on the southwest coast of Madagascar, near the tip of Madagascar, 180 meters (590 ft) high and 5 kilometres (3.1 mi) inland. Chevrons such as Fenambosy have been hypothesized as providing evidence of "megatsunamis" caused by comets or asteroids crashing into Earth. However, the megatsunami origin of the Fernambosy and other chevrons has been challenged by other geologists and oceanographers.
Aguilera is a stratovolcano in southern Chile, which rises above the edge of the Southern Patagonian Ice Field. It is a remote volcano that was identified as such in 1985, but the first ascent only occurred in 2014, making it the last unclimbed major Andean volcano.
The Burckle crater is an undersea topographic feature about 29 kilometres in diameter in the southwestern Indian Ocean. A team of Earth scientists called the Holocene Impact Working Group proposes the feature to be an impact crater; these claims are disputed by other geologists.
The 1958 Lituya Bay earthquake occurred on PST with a moment magnitude of 7.8 to 8.3 and a maximum Mercalli intensity of XI (Extreme). The strike-slip earthquake took place on the Fairweather Fault and triggered a rockslide of 30 million cubic meters and about 90 million tons into the narrow inlet of Lituya Bay, Alaska. The impact was heard 80 kilometers (50 mi) away, and the sudden displacement of water resulted in a megatsunami that washed out trees to a maximum elevation of 524 meters at the entrance of Gilbert Inlet. This is the largest and most significant megatsunami in modern times; it forced a re-evaluation of large-wave events and the recognition of impact events, rockfalls, and landslides as causes of very large waves.
North African climate cycles have a unique history that can be traced back millions of years. The cyclic climate pattern of the Sahara is characterized by significant shifts in the strength of the North African Monsoon. When the North African Monsoon is at its strongest, annual precipitation and consequently vegetation in the Sahara region increase, resulting in conditions commonly referred to as the "green Sahara". For a relatively weak North African Monsoon, the opposite is true, with decreased annual precipitation and less vegetation resulting in a phase of the Sahara climate cycle known as the "desert Sahara".
Marine Isotope Stage 5 or MIS 5 is a marine isotope stage in the geologic temperature record, between 130,000 and 80,000 years ago. Sub-stage MIS 5e, called the Eemian or Ipswichian, covers the last major interglacial period before the Holocene, which extends to the present day. Interglacial periods which occurred during the Pleistocene are investigated to better understand present and future climate variability. Thus, the present interglacial, the Holocene, is compared with MIS 5 or the interglacials of Marine Isotope Stage 11.
Paleotempestology is the study of past tropical cyclone activity by means of geological proxies as well as historical documentary records. The term was coined by American meteorologist Kerry Emanuel.
The Garth tsunami is a likely prehistoric tsunami off the Shetland Islands that may have occurred 5,500 years ago. Its origin is unknown; impact events, earthquakes, and submarine landslides similar to the Storegga Slide 8,100 years ago have been proposed as factors contributing to the event. Evidence suggests a run-up of more than 10 metres (33 ft) in the Shetland Islands. It probably had great impact on coastal communities in the region; mass burials dating approximately to that time in the Shetland and Orkney Islands have been interpreted to host its fatalities.
Lake Estancia was a lake formed in the Estancia Valley, central New Mexico, which left various coastal landforms in the valley. The lake was mostly fed by creek and groundwater from the Manzano Mountains, and fluctuated between freshwater stages and saltier stages. The lake had a diverse fauna, including cutthroat trout; they may have reached it during a possible past stage where it was overflowing.
Mundafan was a former lake in Saudi Arabia, within presently desert-like areas. It formed during the Pleistocene and Holocene, when orbitally mediated changes in climate increased monsoon precipitation in the peninsula, allowing runoff to form a lake with a maximum area of 300 square kilometres (120 sq mi). It was populated by fishes and surrounded by reeds and savanna, which supported human populations.
A paleotsunami is an ancient tsunami, evidenced by modern technology. Some, such as the one resulting from the asteroid that wiped out the dinosaurs, were megatsunamis. It was over 1 mile (1.6 km) high and was a "global tsunami"; see also Cretaceous–Paleogene extinction event.
