#earth sciences

• Actualism — A geological and philosophical theory stating that the physical, chemical, and biological laws governing the Earth today have operated in the same manner and with the same intensity throughout all past geological epochs. In a philosophical sense, it represents a doctrine that reduces reality exclusively to what is actual, present, or in full development, denying the existence of purely potential forms.
• Aerogeology — A branch of applied geology that utilizes aerial photographs, satellite data, and multispectral images captured from above (from airplanes or drones) to study the geological structure of the Earth's crust, landforms, tectonic faults, and to locate mineral deposits or underground resources without initial ground intervention.
• Allogenic — Produced, determined, or controlled by external factors or forces foreign to the respective system, community, or organism. In ecology, it refers to ecological successions induced by external abiotic changes (e.g., drought, floods); in geology, it is synonymous with allogenetic; in medicine (immunology), it describes a transplant or tissue harvested from an individual of the same species but genetically distinct.
• Allogeneity — The quality or characteristic of being allogenous; the state of an element, population, or substance being of a different origin and foreign to the indigenous environment in which it is integrated. In social dynamics, it expresses the cultural or ethnic alterity of an immigrant group in relation to the native population, whereas in earth sciences, it indicates the external provenance of mineral deposits within a basin.
• Allochthonous — Having formed or originated elsewhere than its current location of deposition or existence; an element (rock mass, mineral, plant or animal species) foreign to the local environment in which it is integrated. In geology, it defines thrust sheets or sediments transported from great distances by tectonic or water forces, whereas in ecology it designates a species introduced into a biotope distinct from its native range.
• Alpaleologie — A specialized branch of earth sciences dealing with the geological, paleontological, and structural study of high alpine-type mountain massifs during prehistoric epochs. This discipline analyzes stratigraphic evolution, ancient karst topography formation, fossils of altitude-adapted organisms, and glacier dynamics from early geological periods, providing essential data for reconstructing the planetary mountain paleoclimate.
• Arenogeny — The origin, mode of formation, and historical evolution of sand deposits or sandy dunes and beaches within a specific geographical region. From a structural perspective, arenogenia studies the entirety of interactions between tectonic dynamics, petrographic weathering, and climatic factors that determine the emergence and expansion of fine silica particle networks in the Earth's crust.
• Bachelite — A rare mineral or a structural petrographic variety described in old geological reference works, sometimes used as a spelling variant for industrial bakelite or as a regional name for a certain type of compact sedimentary rock. In contemporary vocabulary, it is monitored to prevent confusion with bakelite (the plastic material), representing a strictly technical term within a narrow geological niche.