Corals from the Tithonian Carbonate Complex in the D¥Browa Tarnowska–Szczucin Area (Polish Carpathian Foreland)
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Annales Societatis Geologorum Poloniae (2012), vol. 82: 1–38. CORALS FROM THE TITHONIAN CARBONATE COMPLEX IN THE D¥BROWA TARNOWSKA–SZCZUCIN AREA (POLISH CARPATHIAN FORELAND) El¿bi eta MO RY COWA Jagiel lo nian Uni ver sity, In sti tute of Geo logi cal Sci ences, Ole an dry 2a, 30- 063 Kraków, Po land, e- mail: el zbi eta.mo [email protected] Mory cowa, E., 2012. Cor als from the Ti tho nian car bon ate com plex in the D¹browa Tar nowska–Szczu cin area (Pol ish Car pa thian Fore land). An nales So cie ta tis Ge olo go rum Po lo niae, 82: 1–38. Ab stract: The stud ied cor als have been col lected from cores of bore holes lo cated in the cen tral part of the Pol ish Carpa thian Foreland in the D¹browa Tarnows ka–Szczu cin area. The Juras sic com plex in this area presents a con tinu ous stra tigraphic sec tion from the Up per Cal lovian to Ti tho nian, lo cally passing to the Lower Cre ta ceous (Ber ria sian). Its thick ness ex ceeds 1,100 m in this area. This com plex is com posed of marine, mainly shallow- water de posits. The cor als oc cur within the up per part of the Upper Ju ras sic (Ti tho nian) de posits, al most entirely within the Swarzów Limestone For mation (= coral- algal limestone for mation). This oc cur rence marks the north ern most extent of Ti tho nian shallow- water cor als in Po land and one of the north ern most in Europe. 42 coral spe cies (among them 14 in open no mencla ture) were iden ti fied in de posits of this for mation. They in clude two new species: Com plex as trea magna and Com plex as trea dab ro vi en sis. All taxa, ex cept one, be long to the or der Sclerac tinia. The described assem blage dis plays a Late Juras sic charac ter. The broader stra tigraphic span is as signed to some spe cies, which are quoted from the Mid dle Ju ras sic and some spe cies lasted un til the Early Cre ta ceous, Ber ria sian and/or Valang in ian. Key words: Scler ac tin ian cor als, car bon ate plat form, Ti tho nian, Car pa thian Fore land, Po land. Manu script re ceived 22 July 2011, ac cepted 27 December 2011 IN TRO DUC TION Nu merous papers (Mo rycowa, 1971, 1976, 1985; Mo - in the upper m ost part of the car bon ate sec tion; they are not, rycowa & Moryc , 1976; Golonka, 1978; Urbanie c & Œwi et- how ever, suf fi ciently bi os tra tigraphi cally docu mented in lik, 2003; Król, 2004; Maty ja & Barski, 2007; Maty ja, this region (Maty ja, 2009; Mory cowa & Moryc , 1911). The 2009) no ticed the oc cur rence of the Late Ju ras sic scler ac tin - shallow- water Scler ac tin ian cor als are de rived from the up - ian corals in the boreholes from the Carpa thi an Fore land, per part of the Upper Juras sic depos it s, al most en tirely from and de scribed litho logi cal char ac ter is tics of coral- bearing the Swarzów Limestone For ma tion (= coral-al gal lime stone depos it s. This fauna has not been de ter mined taxonom i- form ati on). The thickness of this form ati on in the study area cally. Only few de ter mined coral speci mens were con tained is around 140–180 m (Mory cowa & Moryc , 1976). The Ti- in the broad synthe sis of the Up per Juras sic micro fa cie s thonian age of this form ati on was assum ed on the basis of (Mo ry cowa & Mo ryc, 1976). or ganic cysts of di no flag el lates (Ma tyja & Bar ski, 2007; It is note worthy that the oc currence of Titho nian shal- Barski & Maty ja, 2008; Maty ja, 2009) and calpi onel li ds low-wa ter corals from the studied region marks their north- (Mory cowa & Moryc , 2011). The descri bed coral spe cies ernm ost ex tent in Poland and one of the north ernm ost in belong to 26 genera, 11 famili es, 6 sub orders and 2 orders. Europe. The coral as semblage dis plays a Late Ju ras sic char ac ter. It The re cently inves ti gated corals come from eight bore- con tains spe cies com mon in the Mid dle Ox for dian–Kim me- holes from the D¹browa Tar nowska–Szczu cin area (Swa- ridgian faunas from the Peri- Tethyan and Te thyan depos it s rzów 3, 4, 8, 10, D¹browa Tarnowska l, 4, Smêgorzów 2 in Europe and West ern Asia, as well as from the Titho nian; and D¹brówki Breñskie 1; Fig. 1). The substa nti al secti on of some species lasted un til the Early Creta ceous, Ber ria sian the Up per Juras sic depos it s, more than 1,100 m thick, was and/or Valang inian of the Euro pean Tethy an facie s (cf. Mo - drilled in this area (Mo rycowa & Moryc , 1976). This com - rycowa, 1968; Eliášová, 1990; Ro niewicz, 2008). The plex con tains en tirely car bon ate de pos its en com pass ing the broader stra tigraphic span is assigne d to some spe cies, lat est Mid dle Ju ras sic (Late Cal lovian) to Ti tho nian in clu - which are quoted from the Middle Ju rassic (cf. Pandey & sively. Probably , also younger depos it s (Berria sian) occur Fürsic h, 2003, 2006). 2 E. MORYCOWA MA TE RIAL AND METH ODS Uni ver sity, Kraków (coll. E. Mo ry cowa, ac ro nym: UJ 217P). The re spec tive samples with cor als were marked by The in vesti gated coral fauna con tains about 70 speci- subse quent num bers (1, 2, ...), and some sam ples added at a mens, from which about 140 thin secti ons were made in the later time were marked accord ingl y by num bers (2A, 5A, In sti tute of Geo logi cal Sci ences, Jagiel lo nian Uni ver sity in 5B). The thin sec tions were marked by specim en num bers Kraków. These inves ti gati ons were carrie d out with the help and suc ces sive al pha bet let ters (e.g., la, 1b…). In cases, of bin ocu lar and pet ro graphic mi cro scopes. when more than one taxon is present in the given sam ple, The speci mens de scribed below are housed in the Mu- the sam ples are marked as 2/1, 2/2, ... while thin sec tions as seum of the Insti tute of Geologi cal Sci ences, Jagiel lonian 2/la, 2/2a, etc. GEO LOG I CAL SET TING In the base ment rocks, be low the Mio cene and Upper Cre taceous strata of the Car pa thian Fore land (Fig. 1), an Up per Ju ras sic–Lower Cre ta ceous car bon ate com plex oc - curs. These de pos its en com pass a con tinu ous stra tigraphic sec tion from the Up per Dogger to Titho nian, local ly to the Lower Creta ceous , inclu sive ly. This area belonged to the carbon ate plat form of the northern margin of the Te thys Ocean (Peri- Tethys) dur ing these times. In 1976, Mory cowa and Moryc working on the Upper Ju ras sic de pos its in the D¹browa Tar nowska–Szczu cin area, dis tin guished two lithos tra tigraphic for ma tions within the upper part of the carbon ate com plex: the lower, coral- algal limestone s form ati on and the up per, limestone -dolo- mitic, coquina form ati on. They assigne d the Late Ox fordian (“As tar tian”) age to the lower, coral- algal lime stones for ma - tion; the upper one they in cluded enti rely into the Kim me- ridgian. This idea has been sub ject to certai n changes, due to the weak rec og ni tion of bi os tra tigraphic fac tors dur ing the time of these studies . The changes derive d from later in - ves ti ga tions based on the elabo ra tion of new mi cro fos sil as- sem blages. Such studies contri b uted to a more detai led rec- og niti on of the assem blages’ age and, in effect , of their ”re- ju ve na tion”. Mo ry cowa and Mo ryc (2011) pre sented the ac- tual view concern ing the age of these de posit s, tak ing into account the result s of the newest bios tra tigraphic stud ies of many authors as well as their own inves ti gati ons. The pa pers by Maty ja and Barski (2007), Barski and Maty ja (2008), and Maty ja (2009), which based the stra - tigraphy of the dis cussed depos it s on the or ganic dino flag el- lates, in troduced their own propos als into the in form al lithostratigraphic units of the Upper Juras sic depos it s in this part of the Carpa thi an Fore land, includ ing the region north of D¹browa Tarnowska.