Upper Jurassic &#8211; Lower Cretaceous limestones from the easternmost Getic Carbonate Platform (Southern Carpathians, Romania). Microfacies, microfossils and depositional environments
Authors: Mircescu Cristian Victor , Bucur Ioan I , Pleș George 
Published: March 2022

&lt;p&gt;Carbonate deposits from the easternmost part of the Getic Carbonate Platform form good quality outcrops in the Post&amp;#259;varu and Piatra Mare Massifs (Patrulius 1976). The average thickness of the carbonate succession reaches 400 m in these areas (Patrulius 1976). In the Post&amp;#259;varu Massif, the Mesozoic succession consists of Upper Jurassic&amp;#8722;Lower Cretaceous carbonate deposits which are covered by upper Albian&amp;#8722;Cenomanian Conglomerates (S&amp;#259;ndulescu 1964). In the Piatra Mare Massif, the carbonate succession comprises Callovian&amp;#8722;Berriasian olistoliths which are embedded in the general mass of the upper Aptian Conglomerates (S&amp;#259;ndulescu et al. 1972).&lt;/p&gt;&lt;p&gt;&amp;#160;&amp;#160;We collected approximately 600 limestone samples from various sections, in the Post&amp;#259;varu and Piatra Mare Massifs.&lt;/p&gt;&lt;p&gt;The following sections are located in the Post&amp;#259;varu Massif: Valea Drag&amp;#259;, Drumul Albastru, Larga Mare, V&amp;#226;rful Post&amp;#259;varu, Muchia Cheii-Trei Feti&amp;#539;e, Trei Feti&amp;#539;e-Poiana Secuilor, Trei Feti&amp;#539;e-Cabana Post&amp;#259;varu.&lt;/p&gt;&lt;p&gt;Detailed sampling was performed in the Piatra Mare Massif, in the following sections: Bunloc Est, Bunloc Vest, Cariera Bunloc, Cheile Baciului, Cabana Piatra Mare, Valea G&amp;#226;rcinului, &amp;#536;ura de Piatr&amp;#259;, &amp;#536;ura de Piatr&amp;#259;-V&amp;#226;rful Piatra Mare, Piatra Scris&amp;#259;, Coada Pietrei Mari, &amp;#536;irul St&amp;#226;ncilor, Pe&amp;#537;tera de Ghea&amp;#539;&amp;#259;, Pr&amp;#259;pastia Ursului and Tamina.&lt;/p&gt;&lt;p&gt;The following facies associations were identified: bioclastic intraclastic grainstone/rudstone, coral-microbial boundstone, packstone to floatstone with pelagic microfossils, bioclastic packstone-grainstone, peloidal oncoidic packstone-grainstone, bioclastic grainstone with black pebbles, wackestone with cyanobacteria nodules, fenestral wackestone, non-fossiliferous mudstone.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;The micropaleontological association contains dasycladalean algae [&lt;em&gt;Salpingoporella pygmea &lt;/em&gt;(G&amp;#252;mbel),&lt;em&gt; Petrascula bursiformis &lt;/em&gt;Etallon, &lt;em&gt;Aloisalthella sulcata &lt;/em&gt;(Alth), encrusting organisms [&lt;em&gt;Bacinella&lt;/em&gt; type structures&lt;em&gt;, Crescentiella morronensis&lt;/em&gt; (Crescenti), &lt;em&gt;Koskinobulina socialis &lt;/em&gt;Cherchi &amp; Schr&amp;#246;der, &lt;em&gt;Radiomura cautica&lt;/em&gt; Senowbari-Daryan &amp; Sch&amp;#228;fer, &lt;em&gt;Perturbatacrusta leini &lt;/em&gt;Schlagintweit &amp; Gawlick&lt;em&gt;, Taumathoporella parvovesiculifera &lt;/em&gt;(Raineri)], foraminifera [&lt;em&gt;Bramkampella arabica &lt;/em&gt;Redmond, &lt;em&gt;Coscinoconus alpinus &lt;/em&gt;(Leupold)&lt;em&gt;, Coscinoconus delphinensis (&lt;/em&gt;Arnaud-Vanneau et al.)&lt;em&gt;, Coscinoconus sagittarius &lt;/em&gt;(Arnaud-Vanneau et al.)&lt;em&gt;, Frentzenella involuta &lt;/em&gt;(Mantsurova)&lt;em&gt;, Protopeneroplis striata&lt;/em&gt; Weynschenk, &lt;em&gt;Protopeneroplis ultragranulata&lt;/em&gt; Gorbatchik] and pelagic microorganisms (&lt;em&gt;Calpionella alpina&lt;/em&gt; Lorenz).&lt;/p&gt;&lt;p&gt;The identified microfacies types indicate that carbonate material was deposited in two distinct depositional settings. The first one includes slope to basin areas while the second one comprises inner platform depositional environments. The presence of abundant &lt;em&gt;C. alpina&lt;/em&gt; and various representatives of the genus &lt;em&gt;Coscinoconus&lt;/em&gt; (&lt;em&gt;C. delphinensis,&lt;/em&gt; &lt;em&gt;C. sagittarius&lt;/em&gt;) indicates that deposition continued in the area at least until the lower Berriasian. &lt;em&gt;&amp;#160;&lt;/em&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Acknowledgements&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;This work was supported by a grant of the Romanian Ministry of Education and Research, CNCS-UEFISCDI, project number PN-III-P1-1.1-PD-2019-0456, within PNCDI III&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;strong&gt;References &amp;#160;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Patrulius D (1976) Upper Jurassic&amp;#8722;Lower Cretaceous carbonate rocks in the eastern part of the Getic Carbonate Platform and the adjacent flysch troughs. In: Patrulius D, Dr&amp;#259;g&amp;#259;nescu A, Baltre&amp;#537; A, Popescu B, R&amp;#259;dan S (eds) Carbonate Rocks and Evaporites-Guidebook. International Colloquium on Carbonate Rocks and Evaporites, Guidebook Series 15, Institute of Geology and Geophysics, Bucharest, pp 71-82&lt;/p&gt;&lt;p&gt;S&amp;#259;ndulescu, M., 1964. Geological structure of the Post&amp;#259;varul-Runcu Massif (Bra&amp;#537;ov Mountains) (in Romanian). Anuarul Comitetului Geologic, 34 (2): 382&amp;#8211;422.&lt;/p&gt;&lt;p&gt;S&amp;#259;ndulescu M, Patrulius D, &amp;#536;tef&amp;#259;nescu M (1972 a) Geological Map of Romania, scale 1:50 000, Bra&amp;#537;ov Sheet, 111 a (in Romanian). Institutul Geologic, Bucure&amp;#537;ti&lt;/p&gt;