Summary:
This dissertation was prepared at the National Kapodistrian University of Athens, at the De-partment of Geology and Geoenvironment. It concerns the study of the petrological and petrochem-ical composition of the plutonium penetration of Maronia, in SE Thrace.
The group of rare earths consists of fifteen chemical elements, group of lanthanides, from La to Lu, including the elements Sc and Y, which have many common properties. They are classified in metals and have a common strength of 3+. They have a wide range of technological applications, es-pecially in manufacture of high-tech products (liquid crystal displays, mobile phones, lasers, etc.) and in "green" technologies (eg electric car batteries, photovoltaics, wind turbines). The distribution of deposits, the increased demand, as well as their wider use in cutting-edge industrial applications classify them as critical metals and are a top research goal. Actinides are a group of elements in the Periodic Table, from Ac to Lr. Of these, only Ac, Th, Pa and U exist in nature. They have range in the oxidation number and are radioactive. The best known elements are U and Th, which are used as nuclear fuels.
The Maronia plutonite is located in SE Rodopi, and has a great depositological interest, among other things, due to the abundance of minerals from rare earths and actinides in large crystals in its parts. Plutonite has penetrated into marbles and shales of the Circum- Rhodope Belt and is characterized by a variety of lithological types: monzogabbro, monzonite- quartz monzonite, and small gabbroic and granitic bodies. The latter is also associated with porphyry type Cu-Mo ±(Au,Re) ore. The aim of the present work is the mineralogical study of the mineralization of lanthanides and actinides, as well as the geochemical study of plutonite, in order to determine the geotectonic envi-ronment of its creation.
Samples from the southern part of the plutonite appearance were studied microscopically us-ing polarizing microscope, scanning electron microscope (SEM / EDS), and by total chemical analy-sis (XRF and ICP-MS). Their mineral composition includes plagioclase, K feldspars, and a minimum percentage of quartz. In addition, pyroxenes, amphiboles, biotite, titanite and epidote appear. The main mineral found is magnetite. Significant amounts of LREE are contained in large (5-50μm) mineral crystals such as apatite, allanite, monazite and zirconium. The minerals of kiwifruit found are uraninite, zircellite and mainly uraniothorite and thorite. The main metallic mineral found is magnetite. Significant amounts of LREE are contained in large (5-50μm) mineral crystals such as apatite, allanite, monazite and zirconium. The minerals of actinides found, are uraninite, zircellite and mainly uraniothorite and thorite.
In petrographic and petrochemical aspect, the studied samples are classified as monzonites, which belong to the Shoshonite to high-K alkaline series and have characteristics of I-type granitoid-monzanite
