Geologica Acta https://revistes.ub.edu/index.php/GEOACTA <p><strong><span style="font-size: 11.5pt; line-height: 107%; font-family: Verdana, sans-serif; color: #c55a11; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;"><a href="https://revistes.ub.edu/index.php/GEOACTA/libraryFiles/downloadPublic/172" target="_blank" rel="noopener">50th (1966-2016)</a></span></strong></p> <p><span style="color: #c55a11; font-family: Verdana, sans-serif;"><span style="font-size: 15.3333px;"><strong>Journal Citation Reports </strong></span></span><strong style="font-size: 15.3333px; color: #c55a11; font-family: Verdana, sans-serif;">(ISI)</strong></p> <p><img style="float: left; margin: 10px;" src="https://revistes.ub.edu/public/site/images/admingeac/imagen1.png" alt="" width="249" height="230" /></p> <p style="text-align: justify;"><br />An international general Earth Science Journal providing an innovative and high-quality means of scientific dissemination, with researchers and specialists in the Earth Science field as the main audience. Geologica Acta is a non-profit DIAMOND OPEN ACCESS (neither submission nor reading fees are charged) which has the aim to stimulate rapid diffusion of results and efficient exchange of ideas between the widespread communities of researchers in Earth Science. Since 2019, in accordance with current standards, Geologica Acta publishes continuously in an annual volume.</p> <p> </p> <hr style="color: #e4af00;" /> <p> </p> Universitat de Barcelona en-US Geologica Acta 1696-5728 <p><strong>Copyright</strong></p> <p>Geologica Acta is the property of the UB, GEO3BCN, IDAEA and UAB. Geologica Acta must be cited for any partial or full reproduction. Papers are distributed under the <a href="http://creativecommons.org/licenses/by-sa/4.0/">Attribution-Share Alike Creative Commons License</a>. This license allows anyone to reproduce and disseminate the content of the journal and even make derivative works crediting authorship and provenance and distributing possible derivative works under the same or an equivalent license.</p> <p><strong>Author Rights</strong></p> <p>Authors retain the copyright on their papers and are authorized to post them on their own web pages or institutional repositories. The copyright was retained by the journal from the year 2003 until 2009. In all cases, the complete citation and a link to the Digital Object Identifier (DOI) of the article must be included. </p> <p>The authors can use excerpts or reproduce illustrations of their papers in other works without prior permission from Geologica Acta provided the source of the paper including the complete citation is fully acknowledged.</p> Mineral chemistry and P-T conditions of the Karakaya volcanites at Kırka-Afyon-Isparta volcanic province, Afyon, Turkey https://revistes.ub.edu/index.php/GEOACTA/article/view/41984 <p>The Kırka-Afyon-Isparta Volcanic Province (KAIVP) is one of the best known regions in Turkey for the origin and petrological evolution of the high potassium volcanic activity. The temporal and spatial variability of volcanic rocks in the region exerts significant control over their geochemical diversity. Alkaline and ultrapotassic volcanic rocks of the Afyon volcanism are the first products of asthenospheric origin after the orogenesis in western Anatolia. We have determined the mineralogical and petrographic properties of the Karakaya volcanites surrounding Afyon with the help of microprobe analyses. Estimated thermobarometers are calculated. The Karakaya volcanites have been grouped into four different units according to their their mineralogical, petrographic and geochemical characteristics: Seydiler ignimbirite, basaltic trachyandesite, trachyandesite, trachyte and lamproite. Most samples display hypocrystalline porphyritic texture, whereas samples of lamproite unit have a holocrystalline texture. Generally, volcanic units also exhibit some textural evidence of disequilibrium crystallisation, such as sieve texture and corrosion in plagioclase phenocrysts, zoning and inclusions in clinopyroxene phenocrysts. Mineral thermobarometric estimations in all suites were tested on clinopyroxene and feldspar compositions, considering different authors’ approaches. Values of temperatures and pressure range from 1105 to 1273ºC and 5.6 to 12.2kbar, respectively. The temperature and pressure values calculated from the mineral-melt associations in the volcanics suggest that the Afyon Volcanites were affected by magma mixing processes and crystallised at different depths during the transport of magma.</p> irem Aksoy Yaşar KİBİCİ Copyright (c) 2024 irem Aksoy, Yaşar KİBİCİ https://creativecommons.org/licenses/by-sa/4.0 2024-05-10 2024-05-10 22 1 21 10.1344/GeologicaActa2024.22.2 Petrogenesis of the late Miocene Chenar volcanism in the southeast Urumieh-Dokhtar magmatic belt, Kerman, Iran: evidence from geochemical, U-Pb geochronologic, and Hf isotopic constraints https://revistes.ub.edu/index.php/GEOACTA/article/view/42777 <p>The Chenar volcanic cone intruded the southeastern part of the Dehaj-Sarduiyeh volcano-sedimentary belt, in the southeast Urumieh-Dokhtar magmatic arc in Iran. The adakitic rocks, with porphyritic texture, mainly consist of rhyodacites and dacites,commonly comprised of phenocrysts of plagioclase, hornblende and biotite, with rare K-feldspar in a groundmass composed of plagioclase, K-feldspar and quartz. They yielded U-Pb zircon ages of 5.52±0.099Ma, 5.46±0.12Ma, and 6.44±0.12Ma, and radiogenic ɛHf(t) values ranging from +3.1 to +12.7. The whole-rock geochemical analysis of these rocks reveals transitional calc-alkaline to shoshonitic characteristics.</p> <p><br />The geochemical characteristics of the study rocks, particularly their high Sr/Y (⁓51.6-136.8) at low Y (⁓4.43–16.2ppm) and high La/Yb (⁓28.4–118.4ppm) at low Yb (⁓0.2–1.3ppm), are coherent with a high silica adakitic signature. The whole-rock positive Eu/Eu* anomaly and zircon Ce/Ce* anomaly reflect the effects of an oxidized magmatic signature where the rocks of the study area originated from a mantle source. The high silica adakite geochemical characteristics of the Chenar volcanic cone support formation by partial melting of the modified mantle under the influence of metasomatized subducted oceanic slab in a post-collisional environment.</p> Hamideh Salehi Nejard Elham Shahosinie Asma Nazarinia David R. Lentz Copyright (c) 2024 Hamideh Salehi Nejard, Elham Shahosinie, Asma Nazarinia, David R. Lentz https://creativecommons.org/licenses/by-sa/4.0 2024-01-29 2024-01-29 22 1 IV 10.1344/GeologicaActa2024.22.1 A MATLAB approach for developing digital rock models of heterogeneous limestones for reactive transport modeling https://revistes.ub.edu/index.php/GEOACTA/article/view/43029 <p>Porosity is a key parameter controlling the physico-chemical behavior of porous rocks. Digital rock physics offers a unique technique for imaging the inherently heterogeneous rock microstructure at fine spatial resolutions and its computational reconstruction, through which a better understanding and prediction of the rock behavior can be achieved. In this study, we propose a simple but accurate method to build a 3D porosity map of centimeter-scale carbonate rock cores from X-ray Micro Computed Tomography (XMCT) imaging data. The method consists of 3 main steps: i) decomposition of 3D volumetric XMCT data into sub-volumes, ii) processing of equidistributed 2D cross-section images in each sub-volume and iii) 2D slice-by-slice calculation of porosity and its assembly to reconstruct a 3D continuum porosity map over the whole core domain using a MATLAB code. The proposed approach significantly conserves the required memory to manipulate large image datasets. The digitized porosity representations are used to build 3D permeability maps of the cores by applying an explicit permeability-porosity relationship. The permeability maps are used as input for numerical simulation of the rock response to the percolation of reactive fluids through which the general validity of the approach is verified. The developed digital rock model paves the way for an improved understanding of reactive transport in carbonate rocks.</p> Atefeh Vafaie Josep M. Soler Jordi Cama Iman R. Kivi Victor Vilarrasa Copyright (c) 2024 Atefeh Vafaie, Josep M. Soler, Jordi Cama, Iman R. Kivi, Victor Vilarrasa https://creativecommons.org/licenses/by-sa/4.0 2024-06-10 2024-06-10 22 1 14 10.1344/GeologicaActa2024.22.3