Descripción del proyecto
Los defectos reticulares del cuarzo podrían desvelar procesos de formación de rocas
El análisis de procedencia ayuda a los geólogos a identificar la región de origen de las muestras de sedimentos. El cuarzo es uno de los minerales más comunes en la formación de rocas. Los cristales de cuarzo contienen una gran cantidad de defectos puntuales, que se suelen emplear para datar sedimentos cuaternarios. Sin embargo, aún no se comprende del todo la formación y la dinámica de estos defectos. El proyecto PROGRESS, financiado con fondos europeos, tiene por objeto demostrar que los defectos puntuales del cuarzo pueden ofrecer pruebas del metamorfismo de las rocas y desvelar procesos de meteorización, transporte o reciclaje. Sus investigadores combinarán la luminiscencia con técnicas de microscopia para estudiar estos defectos puntuales.
Objetivo
Quantitative provenance analysis studies are instrumental in understanding the tectonic and climatic processes that are shaping Earth`s landscape. Although the most abundant mineral in the sedimentary system is quartz, almost all studies in provenance analysis investigate accessory minerals. Quartz crystals contain a vast number of point defects, intrinsic or due to impurities. Although our understanding on the formation and dynamics of these defects is far from complete, a few of these defects in quartz are used for dating Quaternary sediments by luminescence (thermoluminescence (TL) or optically stimulated luminescence (OSL)) or by electron spin resonance (ESR). PROGRESS aims at proving that point defects in quartz have also the capacity to carry genetic information and their modifications can provide evidence for antiquity, metamorphism (or lack thereof) as well as knowledge on weathering, transport, or recycling. This information can be unravelled by ESR and luminescence methods in combination with microscopic techniques such as scanning electron microscopy coupled with cathodoluminescence (CL) wavelength resolved spectroscopy. To understand changes that are occurring at atomic level in quartz in nature in geological time, PROGRESS will investigate quartz grains extracted from independently dated old to young quartz-bearing continental crustal sources, metamorphosed rocks versus their unmetamorphosed equivalents, fresh versus highly weathered samples, as well as intrusive versus volcanic rocks, besides conducting experiments in laboratory environments. To tackle nature`s complexity during sediment movement in space and time the effect of physical and chemical changes that occur during transport of quartz grains will be investigated by the study of river sediments that drain different lithologies. These investigations will allow a simple quartz based fingerprinting method to be developed, that will have a significant impact on quantitative provenance studies.
Ámbito científico
Programa(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Régimen de financiación
ERC - Support for frontier research (ERC)Institución de acogida
400084 Cluj Napoca
Rumanía