First Evidence of Lamprophyric Magmatism from the Konya Region, Turkey: a Genetic Link to High‐K Volcanism

Abstract

In the vicinity of Konya (Turkey), mafic, micro‐porphyritic sub‐volcanic rocks intrude into the Mesozoic units, which represents the only example of such a rock type in the region. 40Ar/39Ar dating of two whole rock samples from the sub‐volcanics gave ages of 13.72±0.13 and 12.40±0.11 Ma, suggesting temporal association to the Late Miocene‐Pliocene high‐K calc‐alkaline volcanism in the region. The mineral chemistry and geochemical data permit us to classify the rocks as “minette” lamprophyres. They include diopside and phlogopite phenocrysts in a microcrystalline groundmass composed of sanidine, phlogopite, diopside and titano‐magnetite. Segregation and ocelli‐like globular structures occur commonly in the samples. In terms of major elements, the lamprophyres are calcalkaline, and potassic to ultrapotassic rocks. All the lamprophyres display strong enrichments in LILE (Rb, Ba, K, Sr), radiogenic elements (Th, U) and LREE (La, Ce) and prominent negative Nb, Ta, and Ti anomalies on primordial mantle‐normalized trace element diagrams. Geochemical data suggest that the lamprophyres and high‐K calc‐alkaline rocks in the region derived from a subduction‐modified lithospheric mantle source affected by different metasomatic events. Lamprophyric magmatism sourced phlogopite‐bearing veins generated by sediment‐related metasomatism via subduction, but high‐K calc‐alkaline magmas are possibly derived from a mantle source affected by fluid‐rich metasomatism.

Geological Characteristics of the Neogene Volcanic Plugs in Inlice (Konya) Area, Central Turkey

“…Various volcanic and volcano-sedimentary units form in the region, namely, ignimbrite, nuée ardentes, volcanic breccias, agglomerates, tuffs, tuffites, lava flows, lava domes, dikes and sill, with composition of rhyolite, dacite, andesite, trachyandesite, basaltic trachyandesite, basalts and lamprophyres e.g. [9][10][11][12][13][14][15][16]. In the area, the volcanism also leads to the development of some economic mineralizations, such as Doğanbey Cu-Mo porphyry and Inlice Au epithermal deposits [17][18].…”

Indirect Associations Between Lamprophyres and Gold-Copper Deposits

“…Wyman 1990), Sulu Orogen, E China (Guo et al 2004), Yunnan Province, SW China (e.g. Lu et al 2015b), NW Iran (Aghazadeh et al 2015), NW Mexico (Orozco-Garza et al 2013), Central Oman (Worthing and Nasir 2008), and Turkey (Asan and Ertürk 2013;Karsli et al 2014).…”

Reply to “Geochemical Characteristics of Anatolian Basalts: Comment on ‘Neogene Uplift and Magmatism of Anatolia: Insights from Drainage Analysis and Basaltic Geochemistry’ by McNab et al.”

“…A small number of newly included analyses from the Konya province of Central Anatolia have significantly elevated ratios of K/Nb and Ba/Nb. (Figures 1f-1g) These lamprophyres probably represent small melt fractions from an enriched source (Asan & Ertürk, 2013). Note that their low Pb/Ce ratios as well as a lack of isotopic measurements mean that it is difficult to determine whether they are the products of arc volcanism or lithospheric contamination (Figures 1h-1j).…”