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Topic Review
Cenozoic Basins-evolution Eastern-External Betic Zone
Four main unconformities (1-4) were recognized in the sedimentary record of the Cenozoic basins of the eastern External Betic Zone. More in detail, they are located at different stratigraphic levels as follows: (1) Cretaceous-Paleogene boundary even if this unconformity was also recorded at the early Paleocene (Murcia sector) and early Eocene (Alicante sector); (2) Eocene-Oligocene boundary and quite synchronous in the whole considered area; (3) early Burdigalian, and quite synchronous (recognized in the Murcia sector); (4) middle Tortonian (recognized in Murcia and Alicante sectors). These unconformities correspond to stratigraphic gaps of different temporal extensions with different meanings, which allowed recognizing minor sedimentary cycles in the Paleocene-Miocene time span. The Cenozoic marine sedimentation started over the oldest unconformity (i.e. the principal one), above the Mesozoic marine deposits. Paleocene-Eocene sedimentation shows numerous tectofacies (such as: turbidites, slumps, olistostromes, mega-olistostromes and pillow-beds) interpreted as related to an early, blind and deep-seated tectonic activity, acting in the more internal subdomains of the External Betic Zone as a result of the geodynamic processes related to the evolution of the westernmost branch of the Tethys. The second unconformity resulted from a Oligocene to Aquitanian sedimentary evolution in the Murcia Sector from marine realms to continental environments. This last time interval is characterized as the previous one by a gentle tectonic activity. On the other hand, the Miocene sedimentation was totally controlled by the development of superficial thrusts and/or bend zones of strike-slip faults both related to the regional geodynamic evolutionary framework linked to the Mediterranean opening. These bends of strike-slip faults created subsidence areas (pull-apart basin-type) and affected the sedimentation lying above the third unconformity. By contrast, the subsidence areas were bounded by structural highs affected by thrusts and folds. After the third unconformity, the Burdigalian-Serravallian sedimentation occurred mainly in shallow- to deep-water marine environments (Tap Fm). During the late Miocene, after the fourth unconformity, the activation of the bend zones of strike-slip faults caused a shallow marine environment sedimentation in the Murcia sector and a continental (lacustrine and fluvial) deposition in the Alicante sector represented, the latter resulting in alluvial fan deposits. Furthermore, the location of these fans changed over time according to the activation of faults responsible for the tectonic rising of Triassic salt deposits, which fed the fan themselves.
  • 1.9K
  • 10 Oct 2020
Topic Review
DSGSDs on Mars
Deep-Seated Gravitational Slope Deformations (DSGSDs) are a set of slow and complex gravity-driven deformational processes, involving entire slopes (or large portions of them) over long time intervals. These phenomena have been identified on Mars since the early 2000s, and several detailed studies were conducted on them.
  • 1.8K
  • 29 Apr 2021
Topic Review
Zagros Fold and Thrust Belt
The Zagros fold and thrust belt (Zagros FTB) is an approximately 1,800-kilometre (1,100 mi) long zone of deformed crustal rocks, formed in the foreland of the collision between the Arabian Plate and the Eurasian Plate. It is host to one of the world's largest petroleum provinces, containing about 49% of the established hydrocarbon reserves in fold and thrust belts and about 7% of all reserves globally.
  • 1.8K
  • 08 Nov 2022
Topic Review
Debris Flow Hazard
Global climate change has increased severe torrential hazards, particularly debris flows in mountainous regions. After floods and earthquakes, debris flows are the most devastating natural hazard in the world. The effects of debris flow on human life and built environments necessitate reconsidering current infrastructure planning, engineering, and risk management practices. Hence, the vulnerability of elements at risk is critical for effective risk reduction systems.
  • 1.8K
  • 27 Dec 2022
Topic Review
The UNESCO Site of the Chaîne des Puys
The tectono-volcanic ensemble of the Chaîne des Puys and the Limagne fault, which is part of the West European rift, was inscribed on the UNESCO World Heritage list in 2018 as the Chaîne des Puys–Limagne fault tectonic arena.
  • 1.7K
  • 25 Sep 2023
Topic Review
Coastal Adaptation to Sea-Level Rise
The Earth’s climate is changing; ice sheets and glaciers are melting and coastal hazards and sea level are rising in response. With a total population of over 300 million people situated on coasts, including 20 of the planet’s 33 megacities (over 10 million people), low-lying coastal areas represent one of the most vulnerable areas to the impacts of climate change. The need to identify and implement adaptation solutions to the impacts of climate change in coastal zones is urgent. 
  • 1.7K
  • 17 Aug 2021
Topic Review
Iron Silicides
Iron silicide minerals (Fe-Si group) are found in terrestrial and solar system samples. These minerals tend to be more common in extraterrestrial rocks such as meteorites, and their existence in terrestrial rocks is limited due to a requirement of extremely reducing conditions to promote their formation. Such extremely reducing conditions can be found in fulgurites, which are glasses formed as cloud-to-ground lightning heats and fuses sand, soil, or rock. 
  • 1.7K
  • 19 Apr 2022
Topic Review
Measure the Height of Mount Everest
Mount Everest is the highest mountain in the world. First, we should know where is Mt. Everest located on the plateau of Tibet map. It is on the border of Nepal and Tibet(the Autonomous Region of China). The determination of the height of Mount Everest(HME) is one of the focuses of the geodetic community. The shallow layer method (SLM) based on the definition of the geoid can determine the gravity field inside the shallow layer. The orthometric height of Mount Everest (HME) is calculated based on SLM, in which the key is to construct the shallow layer model. The top and bottom boundaries of the shallow layer model are the natural surface of the Earth and the surface at a certain depth below the reference geoid, respectively. 
  • 1.7K
  • 31 Jan 2024
Topic Review
Uturunku
Uturunku (Quechua for jaguar, Hispanicized spellings Uturunco, Uturuncu) is a dormant volcano in the Cordillera de Lípez in Potosí Department, Bolivia. It is located in the Sur Lípez Province, San Pablo de Lípez Municipality. It is in the Central Volcanic Zone of the Andes, and its highest summit is 6,008 metres (19,711 ft) above sea level. The volcano has two summits, with a fumarole field between them. The volcano's landforms include lava domes and lava flows. The volcano was sporadically active during the Pleistocene, with the most recent eruption dated at 271,000 years ago. Since then, Uturunku has displayed fumarolic activity. Starting in 1992, satellite observations have indicated a large area of regional uplift centered on Uturunku, which has been interpreted as an indication of large-scale magma intrusion under the volcano. This might be a prelude to large-scale volcanic activity, including "supervolcanic" activity and caldera formation.
  • 1.7K
  • 29 Sep 2022
Topic Review
Tectonic Archaeology
Tectonic Archaeology is conceived as an umbrella term for efforts to deal with evidence of volcanic eruptions, earthquakes, and tsunami in the archaeological record and the consequences for society. It also can serve as a foundation for Geoarchaeology in general.
  • 1.6K
  • 28 Sep 2021
Topic Review
Application of Nanomaterials in Enhanced Oil Recovery
The implementation of nanoparticles in Enhanced Oil Recovery (EOR) techniques is a novel method that has proven to increase the recovery of oil in place more than conventional EOR processes in most cases. The main aim of integrating nanoparticles in EOR methods is to boost the performance of each EOR technique by enhancing one or more parameters or mechanisms related to the recovery method. Sometimes, adding nanoparticles to the EOR method might reduce oil recovery due to porosity reduction, injection blockage, aggregation, and settling problems. The utilization of nanomaterials in several EOR applications comes with many benefits, such as IFT reduction, wettability alteration, and mobility improvement.
  • 1.6K
  • 02 Feb 2023
Topic Review
Fissure Ridges
Fissure ridges consist of elongated travertine masses with an apical fissure that follows the long axis of the body. Two symmetrical or asymmetrical walls made up of bedded travertine are typically dipping away from the central fissure. The internal part of the fissure is often cut by a network of sealed fractures, almost parallel to the long axis of the ridge, normally filled by banded Ca-carbonate (i.e., calcite and/or aragonite), almost parallel to the vein-walls (the so called “banded travertine” in). These veins developed within the fault zone and represent conduits along which geothermal fluids move towards the surface. Therefore, their analysis, in terms of geometry, age (using U/Th, U/Pb, and 14C geochronology), and geochemical properties, provides information about the structural features and timing of the fault system, and on the fluid path from depth to surface. Furthermore, travertine deposited in a fissure ridge is characterized by distinct petrographic and geochemical features preserving information on the parent fluids and ancient depositional conditions. The shape of the fissure ridge body depends on the flow rate, carbonate precipitation rate, and surface topography upon which deposition took place.
  • 1.6K
  • 13 Jul 2021
Topic Review
Geology and Geomorphology of Mare Fecunditatis
Mare Fecunditatis is a ~310,000 km2 flat basalt plain located in the low-latitude area of the Moon. Mare Fecunditatis basin was formed in the pre-Nectarian period, followed by the mare basalts eruption in the Imbrian period, and the volcanic activity continued until the early Eratosthenian period. There is no mass concentration in the center of Mare Fecunditatis, while there are positive Bouguer anomalies on the east and west sides of the basin. A diversity of geological features is found in Mare Fecunditatis.
  • 1.6K
  • 07 Mar 2022
Topic Review
Groundwater Temperature Measurements
Groundwater temperature (GWT) can be influenced by anthropogenic factors such as surface sealing or geothermal use. These thermal influences can lead to geochemical changes in groundwater, which can affect groundwater quality. Therefore, it is important to measure and monitor GWT. For this purpose, screened monitoring wells (MWs) are usually used. However, temperature measurements can be disturbed by vertical currents within MWs as a result of convection.
  • 1.6K
  • 05 May 2022
Topic Review
Mining Effects on the Karst
Karst develops on soluble rocks (limestone, dolomite, and evaporite). The infiltrating water with carbonic acid creates cavities (caves), fills them, and flows towards the mountain margin (karst water), where it emerges in springs. The infiltrated water constitutes a three-dimensional system whose surface is the karst water level, which undergoes fluctuation of various degrees and periods due to natural and artificial effects, at another time a one-way rise or subsidence. Since karst rocks drain water, neither a surface water network nor valleys develop (they are only formed at sites where the valley is inherited from the non-karstic cover or when the karst water level is situated at the valley floor). The dissolved material is transported into the karst with the infiltrating waters; therefore, surface karst features are closed. These are karren, dolines, ponors with blind valleys, and poljes. The material transported in the solution precipitates as freshwater limestone.
  • 1.6K
  • 05 Dec 2022
Topic Review
Pyrolysis of Technogenic-Redeposited Coal-Bearing Rocks
Hydrocarbon products formed under high-temperature and low-temperature pyrolysis of coal-bearing rocks were studied by using a chromatography-mass spectrometer GCMS-QP2010NC Plus (made by Shimadzu Company). The average temperature of low-temperature natural pyrolysis does not exceed 120°C, and its average speed is approximately 2 m/year. In this case, three pyrolysis zones gradually built metamorphic rock mass (from bottom to top) are clearly established: heating (focal) activated and enriched. The average temperature of high-temperature pyrolysis reaches 850°C, and its average speed is approximately 20 m/year. Unlike low-temperature pyrolysis, high-temperature pyrolysis is accompanied by the presence of two major zones (from bottom to top): pyrogenic (focal) and enriched (coke). The chemical composition of the enriched pyrolysis zone was studied in detail. It has been established that hydrocarbon compounds in samples of the pyrolysis zone are presented by six classes: asphaltic-resinous substances; polycyclic aromatic hydrocarbons, heterocyclic compounds, organic sulphur compounds; pyrolytic hydrocarbon and heavy hydrocarbon residue. Quantitative content of hydrocarbon compounds in the analyzed samples varies from 0.35% to 41.88%.   Based on the materials of fieldwork, we created a video film that can be seen on the website https://youtu.be/Tqs6YiKfDdE
  • 1.5K
  • 29 Oct 2020
Topic Review
Gender Equality in Tanzanite Mine-to-Market
In the mining industry, the contemporary concept of mapping artisanal and small-scale mining to the UN Sustainable Development Goals is a newer aspect of sustainability. SDG 5 aims to achieve gender equality and empower all women and girls. However, while there have been initiatives to support gemstone mining in Tanzania and East Africa, to date, the role of women in the lucrative tanzanite mine-to-market (M2M) supply chain has been less visible and a missed opportunity. This is a concern, as in 2019, pre-COVID-19 pandemic, gemstone and precious metals accounted for an incredible 33.2% of Tanzania’s total exports. In contrast, in leading mining countries such as Australia and Canada, the participation of women continues to steadily advance, economically empowering the women involved.
  • 1.5K
  • 02 Apr 2022
Topic Review
List of Minerals Approved by IMA (F)
This list includes those recognised minerals beginning with the letter F. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 1.5K
  • 07 Nov 2022
Topic Review
Sierra Espuña Cenozoic Malaguide Basin
The Cenozoic Malaguide Basin from Sierra Espuña (Internal Betic Zone, S Spain) due to the qual-ity of outcropping, areal representation, and continuity in the sedimentation can be considered a key-basin. In the last 30 years, a large number of studies with very different methodological ap-proaches have been done in the area. Models indicate an evolution from passive margin to wedge-top basin from Late Cretaceous to Early Miocene. Sedimentation changes from limestone platforms with scarce terrigenous inputs, during the Paleocene to Early Oligocene, to the deep ba-sin with huge supplies of turbidite sandstones and conglomerates during the Late Oligocene to Early Miocene. The area now appears structured as an antiformal stack with evidence of synsedimentary tectonics.
  • 1.4K
  • 19 Jan 2021
Topic Review
Japan Median Tectonic Line
Japan Median Tectonic Line (中央構造線, Chūō Kōzō Sen), also Median Tectonic Line (MTL), is Japan's longest fault system. The MTL begins near Ibaraki Prefecture, where it connects with the Itoigawa-Shizuoka Tectonic Line (ISTL) and the Fossa Magna. It runs parallel to Japan's volcanic arc, passing through central Honshū to near Nagoya, through Mikawa Bay, then through the Inland Sea from the Kii Channel and Naruto Strait to Shikoku along the Sadamisaki Peninsula and the Bungo Channel and Hōyo Strait to Kyūshū. The sense of motion on the MTL is right-lateral strike-slip, at a rate of about 5–10 mm/yr. This sense of motion is consistent with the direction of oblique convergence at the Nankai Trough. The rate of motion on the MTL is much less than the rate of convergence at the plate boundary, making it difficult to distinguish the motion on the MTL from interseismic elastic straining in GPS data.
  • 1.4K
  • 10 Nov 2022
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