Geochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools such as paleomagnetism and stable isotope ratios. By combining multiple geochronological indicators the precision of the recovered age can be improved.
Thermoluminescence dating (TL) is the determination, by means of measuring the accumulated radiation dose, of the time elapsed since material containing crystalline minerals was either heated or exposed to sunlight (sediments). As a crystalline material is heated during measurements, the process of thermoluminescence starts. Thermoluminescence emits a weak light signal that is proportional to the radiation dose absorbed by the material. It is a type of luminescence dating.
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.
Radiation dosimetry in the fields of health physics and radiation protection is the measurement, calculation and assessment of the ionizing radiation dose absorbed by an object, usually the human body. This applies both internally, due to ingested or inhaled radioactive substances, or externally due to irradiation by sources of radiation.
In physics, optically stimulated luminescence (OSL) is a method for measuring doses from ionizing radiation. It is used in at least two applications:
The Kalambo Falls on the Kalambo River is a 235-metre (772 ft) single-drop waterfall on the border of Zambia and Rukwa Region, Tanzania at the southeast end of Lake Tanganyika. The falls are some of the tallest uninterrupted falls in Africa. Downstream of the falls is the Kalambo Gorge, which has a width of about 1 km and a depth of up to 300 m, running for about 5 km before opening out into the Lake Tanganyika rift valley. The Kalambo waterfall is the tallest waterfall in both Tanzania and Zambia. The expedition which mapped the falls and the area around it was in 1928 and led by Enid Gordon-Gallien. Initially it was assumed that the height of falls exceeded 300 m, but measurements in the 1920s gave a more modest result, above 200 m. Later measurements, in 1956, gave a result of 221 m. After this several more measurements have been made, each with slightly different results. The width of the falls is 3.6–18 m.
The Calico Early Man Site is an archaeological site in an ancient Pleistocene lake located near Barstow in San Bernardino County in the central Mojave Desert of Southern California. This site is on and in late middle-Pleistocene fanglomerates known variously as the Calico Hills, the Yermo Hills, or the Yermo formation. Holocene evidence includes petroglyphs and trail segments that are probably related to outcrops of local high-quality siliceous rock.
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as use of the word "absolute" implies an unwarranted certainty of accuracy. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events.
Blombos Cave is an archaeological site located in Blombos Private Nature Reserve, about 300 km east of Cape Town on the Southern Cape coastline, South Africa. The cave contains Middle Stone Age (MSA) deposits currently dated at between c. 100,000 and 70,000 years Before Present (BP), and a Late Stone Age sequence dated at between 2000 and 300 years BP. The cave site was first excavated in 1991 and field work has been conducted there on a regular basis since 1997, and is ongoing.
Greek pyramids, also known as the Pyramids of Argolis, refers to several ancient structures located in the plains of Argolid, Greece. The best known of these is known as the Pyramid of Hellinikon. In the time of the geographer Pausanias it was considered to be a tomb. Twentieth century researchers have suggested other possible uses. The surrounding country of Apobathmi was called Pyramia (Πυράμια), from the monuments in the form of pyramids found there.
Luminescence dating refers to a group of chronological dating methods of determining how long ago mineral grains were last exposed to sunlight or sufficient heating. It is useful to geologists and archaeologists who want to know when such an event occurred. It uses various methods to stimulate and measure luminescence.
In statistics, a Galbraith plot is one way of displaying several estimates of the same quantity that have different standard errors.
Howiesons Poort is a technological and cultural period characterized by material evidence with shared design features found in South Africa, Lesotho, and Namibia. It was named after the Howieson's Poort Shelter archaeological site near Grahamstown in South Africa, where the first assemblage of these tools was discovered. Howiesons Poort is believed, based on chronological comparisons between many sites, to have started around 64.8 thousand years ago and ended around 59.5 thousand years ago. It is considered to be a technocomplex, or a cultural period in archaeology classified by distinct and specific technological materials. Howiesons Poort is notable for its relatively complex tools, technological innovations, and cultural objects evidencing symbolic expression. One site in particular, Sibudu Cave, provides one of the key reference sequences for Howiesons Poort. Howiesons Poort assemblages are primarily found at sites south of the Limpopo River.
Quaternary Geochronology is a peer-reviewed scientific journal addressing methods and results in the dating of samples from the Quaternary Period.
Ioannis Liritzis is professor of physics in archaeology (archaeometry) and his field of specialization is the application of natural sciences to archaeology and cultural heritage. He studied physics at the University of Patras and continued at the University of Edinburgh, where he obtained his Ph.D. in 1980. Since then, he undertook postgraduate work at the University of Oxford, Université Bordeaux III, University of Edinburgh and the Academy of Athens.
The Buttermilk Creek complex is the remains of a paleolithic settlement along the shores of Buttermilk Creek in present-day Salado, Texas. The assemblage dates to ~13.2 to 15.5 thousand years old. If confirmed, the site represents evidence of human settlement in the Americas that pre-dates the Clovis culture.
Chronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such object or event to be located in a previously established chronology. This usually requires what is commonly known as a "dating method". Several dating methods exist, depending on different criteria and techniques, and some very well known examples of disciplines using such techniques are, for example, history, archaeology, geology, paleontology, astronomy and even forensic science, since in the latter it is sometimes necessary to investigate the moment in the past during which the death of a cadaver occurred. These methods are typically identified as absolute, which involves a specified date or date range, or relative, which refers to dating which places artifacts or events on a timeline relative to other events and/or artifacts. Other markers can help place an artifact or event in a chronology, such as nearby writings and stratigraphic markers.
Optically stimulated luminescence (OSL) thermochronometry is a dating method used to determine the time since quartz and/or feldspar began to store charge as it cools through the effective closure temperature. The closure temperature for quartz and Na-rich K-feldspar is 30-35 °C and 25 °C respectively. When quartz and feldspar are beneath the earth, they are hot. They cool when any geological process e.g. focused erosion causes their exhumation to the earth surface. As they cool, they trap electron charges originating from within the crystal lattice. These charges are accommodated within crystallographic defects or vacancies in their crystal lattices as the mineral cools below the closure temperature.
The Riadino-5 Site is an archaeological site located on a terrace within the Šešupė River Valley in the Kaliningrad Oblast of the Russian Federation. Unlike most other sites near this area, the Riadino-5 site is one of the first sites of the Middle to Upper Paleolithic transitional period to have been found in the Baltic region, which includes Lithuania, Latvia, Estonia, and areas of the Russian Federation. Even when compared to other sites of similar age, the Riadino-5 site is still one of the northernmost sites to have been occupied in the Central European region. This makes it one of the oldest sites documenting human habitation, dating back all the way to the Marine Isotope Stage 3, approximately ca 57-26 thousand calendar years ago. The site itself was occupied during the Middle to Upper Paleolithic period within that era between 50 and 44 ka. Upon discovery, the site measured 200 meters by 80 meters. The approximate aging of the site was supported by findings of flint artifacts, using luminescence IRSL dating based on potassium-feldspar sample size and Carbon-14 dating of charcoal and ash layers from the site. At the moment, the exact culture and society of the site occupants has yet to be determined, and is currently undergoing comparative analysis to other similarly dated sites in the vicinity to uncover some answers.
Nauwalabila I, is a sandstone rock shelter located in Deaf Adder Gorge in the Northern Territory of Australia. Along with Madjedbebe, this site is one of the oldest in terms of human settlement in Australia, with its estimated age being greater than 50,000 years. Nowadays, this site can be found in Kakadu National Park, a UNESCO World Heritage site that is partially owned by the collective Aboriginal population of Arnhem Land.
