Evolution and Origin of the Maronia Pluton, Thrace, Greece

Abstract

The Maronia pluton is the youngest of the Tertiary plutons that occurred in Thrace. Three rock groups have been distinguished: a basic, an intermediate and an acid one. Based on geochemical and isotopie characteristics, the basic group probably represents a magma that isotopically equilibrated with the intermediate group at a certain point of its evolution. The evolution of the intermediate group can be described by an assimilation-fractional crystallization process (AFC). The acid group represents crustai melts that are not genetically related to the basic and intermediate groups. The emplacement of the pluton is related to post-collisional extension resulting from the subduction of the African under the European plate. The magma source of the basic and intermediate group is considered to be a LI LE- and LREE-enriched subcontinental lithospheric mantle. The acid group has probably derived by the partial melting of crustai rocks and in particular, gneiss.

The Potential for REE and Associated Critical Metals in Coastal Sand (Placer) Deposits of Greece: A Review

“…Basic rocks are effectively gabbros, intermediate compositions range from (quartz) monzonite to monzogabbro, whereas felsic rocks consist of granite and its porphyritic/aplitic equivalents. The gabbros show high alkali characteristics [67].…”

Extremely Re-Rich Molybdenite from Porphyry Cu-Mo-Au Prospects in Northeastern Greece: Mode of Occurrence, Causes of Enrichment, and Implications for Gold Exploration

“…Cu-Mo-Au mineralization in northeastern Greece (e.g., granodiorite-tonalite porphyry, microgranite porphyry and granodiorite porphyry). Whole-rock geochemical analyses are from [42,49] for Pagoni Rachi and Maronia and this study (Konos, Myli, Melitena). Rock fields are from [50], whereas the boundary between the alkaline and subalkaline fields is from [51].…”

“…In the Maronia area (about 10 km 2 ), Mesozoic rocks of the Circum-Rhodope Belt were intruded by a Tertiary intrusive complex consisting of shoshonitic monzonite-gabbro [49]. This complex was subsequently intruded by a microgranite porphyry (Figure 3), hosting Re-rich porphyry Cu-Mo-Au mineralization [39,49].…”

“…This complex was subsequently intruded by a microgranite porphyry (Figure 3), hosting Re-rich porphyry Cu-Mo-Au mineralization [39,49]. The microgranite porphyry comprises phenocrysts of quartz, K-feldspar, biotite and minor plagioclase in a fine-grained matrix of quartz, K-feldspar and plagioclase.…”

“…More precisely: (a) a LILE-and LREE-enriched sub-continental mantle is the proposed magma source for the Pagoni Rachi and Konos granodiorite-tonalite [95]; (b) a lower crustal origin for the Maronia microgranite [49]; (c) a mantle source for the high-K calc-alkaline granodiorite porphyry at Stypsi [94]; (d) dehydration melting of enriched metabasaltic amphibolite at the base of crust, triggered by rising mantle melts from both the asthenosphere and the enriched subcontinental lithosphere for igneous rocks related to porphyry-style mineralization on Limnos island [96]); and (e) a magma genesis in the upper mantle and subsequent crustal contamination of the parental melts during emplacement of the Skouries deposit [97].…”