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The N–S-trending Sistan Suture Zone in East Iran results from the collision of the Lut and Afghan continental blocks. The southern Sistan Basin hosts Eocene terrigenous deep-marine turbiditic sequences with carbonate olistoliths, debris-flow sheets and calcareous turbidites. These carbonates represent one or several early to middle Eocene carbonate platforms fragmented and redeposited in a deep-marine environment. Palaeocurrent measurements on the terrigenous and calcareous turbidites show that the source carbonate platform was located on the Afghan active margin. Volcanic debris in the limestone and surrounding turbidites corroborate an active magmatic margin on the Afghan side. The formation of limestone debris-flow sheets is attributed to increased erosion and retreat of the carbonate platform, potentially triggered by the closure of the Sistan Basin and continental collisions in the late middle Eocene, after subduction of the Sistan Ocean beneath the Afghan Block. [ABSTRACT FROM AUTHOR]

The Olistostrome member of the Sana-Una Paleozoic complex of the Ljubija ore mine in Bosnia and Herzegovina contains limestone fragments of pebble to block size that have been examined paleontologically. The recovered conodont fauna of the first sample is characterized by the species Declinognathodus lateralis, Idiognathoides sulcatus sulcatus and Idiognathodus sp. confirming its mid-Bashkirian age. This report is the first on the occurrence of these taxa in the area. The second sample with chaetetid demosponges yields an abundant diversified microbiota consisting of cyanobacteria, algae and foraminifera. Chlorophyts are marked by the common siphonoclad occurrence of Donezella lutugini and D. lunaensis, whereas rhodophyts include rare representatives of Stacheia, Stacheoides, Pseudoungdarella and Masloviporidium. The presence of Asphaltinella horowitzi and Aphralysia carbonaria of unclear taxonomic position is also documented. Pseudostaffellids, eostaffellids and other foraminifera, mostly endothyrids are present. The examined associations of fossils point to the Bashkirian age of the primary rock that originated in a very shallow habitat most probably linked to a high-energy reef environment.

The Terek‐Caspian fold‐and‐thrust belt along the northern flank of the Greater Caucasus Mountain Range together with the adjacent foreland basin is one of the oldest oil‐producing regions in Russia. Despite the long history of exploration, recently acquired seismic data has provided new insights about the structural architecture and evolution of this area. Its structural development during the Neogene was constrained by a syn‐extensional tectonic fabric inherited from Jurassic rifting and extension of the Great Caucasus Basin. The structural framework of this basin controlled the distribution of syn‐extensional deposits, and the Cenozoic reactivation of lateral ramps resulted in along‐strike variations in structural style. Thus western, central and SE segments of the Terek‐Caspian foldbelt are recognised and are referred to here as the Terek‐Sunzha fold zone, the Dagestan Promontory, and the Maritime Zone in southern Dagestan. Three principal episodes of Cenozoic compression in the Terek‐Caspian fold‐and‐thrust belt took place. The first episode in the Oligocene resulted in the inversion of pre‐existing normal faults with the coeval development of a foreland basin to the north of the thrust belt. The dominance of sediments of northerly provenance in the foreland basin suggests there was only moderate uplift of the Greater Caucasus at this time. However, significant uplift of the orogenic belt took place during later phases of Sarmatian (Late Miocene) and Akchagylian (Late Pliocene) compression. Erosion of the uplifting Greater Caucasus gave rise to the development of large‐scale, northerly prograding clinoforms which are clearly observed on seismic profiles in the foreland basin. Shortening was largely accommodated by wedge‐shaped thrusting facilitated by the presence of mechanically weak stratigraphic units. Structural development of the Terek‐Sunzha fold zone in the west of the Terek‐Caspian fold‐and‐thrust belt was largely controlled by a Tithonian salt layer which provided an efficient basal detachment surface and which also supplied material to squeezed diapirs in front of the belt. To the east, the plan‐view shape and internal architecture of the Dagestan Promontory were influenced by the areal extent of the Lower‐Middle Jurassic depocentre of the palaeo‐Volga delta which is up to 10 km thick. In the Maritime Zone, the style of shortening was mostly controlled by the presence of a pre‐existing structural high composed of folded Palaeozoic‐Triassic strata in front of the fold‐thrust belt. [ABSTRACT FROM AUTHOR]

In this paper we describe four new fossil associations of “reef” and “reef”-like environments of the St. Cassian Formation (Ladinian-Carnian, Dolomites, NE Italy), based on thirty thin sections from 10 “Cipit boulders” olistoliths, which slided from the Cassian platform into coeval basin sediments. The fossil associations were determined by means of microfacies analysis using point-counting and visual estimation, as well as with aid of statistical methods, based on all fractions with a biotic significance (biomorpha and microbialites). Cluster Analyses in Q-Mode were performed, coupling three algorithms and two indices. In all samples, the main components of the framework are microbialite (average of 75%), and macrofossils (average of 20%), whereas cements and allochtonous components, such as allomicrite, do not represent a significant fraction. Based on both microbialite and fossil content, Chaetetid–microencruster Association, Microbialite–microencruster Association, Dual-type Microbialite Association and Microbialite–Terebella Association, were differentiated. The palaeoenvironmental settings where the associations come from are separately discussed. Microencrusters helped determine energy and luminosity settings. Microencruster abundance and diversity, in addition to the conspicuousness of microbialite, indicate that all associations come either from a deep, or from a cryptic setting.

The Olistostrome member of the Sana-Una Paleozoic complex of the Ljubija ore mine in Bosnia and Herzegovina contains limestone fragments of pebble to block size that have been examined paleontologically. The recovered conodont fauna of the first sample is characterized by the species Declinognathodus lateralis, Idiognathoides sulcatus sulcatus and Idiognathodus sp. confirming its mid-Bashkirian age. This report is the first on the occurrence of these taxa in the area. The second sample with chaetetid demosponges yields an abundant diversified microbiota consisting of cyanobacteria, algae and foraminifera. Chlorophyts are marked by the common siphonoclad occurrence of Donezella lutugini and D. lunaensis, whereas rhodophyts include rare representatives of Stacheia, Stacheoides, Pseudoungdarella and Masloviporidium. The presence of Asphaltinella horowitzi and Aphralysia carbonaria of unclear taxonomic position is also documented. Pseudostaffellids, eostaffellids and other foraminifera, mostly endothyrids are present. The examined associations of fossils point to the Bashkirian age of the primary rock that originated in a very shallow habitat most probably linked to a high-energy reef environment. [ABSTRACT FROM AUTHOR]

In the northeast Iraq, the Maastrichtian turbidite deposits, as a Tanjero Formation, consist of very thick succession of sandstones, conglomerates, and calcareous shales. It deposited in a deep and coastal areas of the Early Zagros Foreland basin which is generated after the radiolarites and limestone obductions during Maastrichtian. The foreland basin was bounded from northeast by newly uplifted and highly elevated active terrestrial land from which voluminous amount of the siliciclastic sediments and carbonates transported to the different parts of the foreland basin. In the studied area, two types of lenticular bodies of synsedimentary mass transport deposits (MTDs) are recorded in the turbidite succession and studied in three outcrop sections about 70 km far from each other. The first type is deposits of coarse grain debris flow, characterized by bad sorting, mud supporting, chaotic internal structures, and bearing angular blocks of olistoliths which reveal instable tectonic setting of the basin. The second is Maastrichtian slump debris within sandstone bedsets (succession) which are extremely deformed, wildly fragmented to blocks of olistoliths and boulders. These deformed bedsets are squeezed between intact and unreformed strata of the lower part of the Tanjero Formation. The slump deposits contain folded sandstone beds and their attitudes indicate, on the stereonet, the southwest transport of the slump deposits. This direction is detected from trends of four fold axes included in the slump debris. The fold axes are extending northeast-southeast which indicate the gravitation stress was in the southwest direction. This study includes a first record of the catastrophic submarine coarse grain debris flow, slumping, and olistolith deposition in the Zagros orogenic belt that uncovers important tectonic setting processes and paleogeographic configuration of the Zagros Collisional Belt during Maastrichtian. [ABSTRACT FROM AUTHOR]

An interpretation of the deep structure of the Pieniny Klippen Belt in Poland is presented, utilizing a high-resolution deep seismic reflection survey. The studied profiles reach a depth of around 23 km. The seismic lines depict the structure and mutual relationships between the main domains analyzed—the Central Carpathians (CC), the Pieniny Klippen Belt (PKB) and the Outer Carpathians. The seismic lines show the Central Carpathian Paleogene (CCP) sediments covering the Tatric units and overlying Krížna and Choč nappes of the CC south of the PKB. The entire nappe pile comprising the CC units is thrust over sedimentary rocks that probably derived from the European Plate, representing a mixture of autochthonous platform Paleozoic to Neogene sediments and slices of Outer Carpathian and PKB rocks. The older crystalline basement of the European Plate is suspected to be below these sedimentary rocks. The reflections below 20 km depth show a possible boundary between different crustal elements within this plate. The PKB is part a of 3–5 km wide flower structure, limited by fault zones that include faults cutting across sediments of the CCP and the Magura Nappe. The fault marking the southern limit of the PKB is particularly well visible in the seismic sections. The Albian–Lower Miocene flysch sequences, constituting the main components of the PKB, form north-vergent thrust-sheets. During the Albian to Miocene the PKB originated as an accretionary prism in front of the moving CC Plate, followed by plate rotation and strike-slip processes. The entire CC nappe pile is thrust over the Precambrian and Lower Paleozoic crystalline basement of the European Plate and probably slices of the PKP. The Outer Carpathians display an allochthonous character above the European Plate and comprise several north-verging imbricated nappes (thrust-sheets). The European plate dips gently southwards below the PKB and the CC Plate, cut by several deep-reaching faults. [ABSTRACT FROM AUTHOR]

Triassic limestones that belong to the Transilvanian Nappe system, form extensive outcrops in the central part of the Perșani Mountains, near Racoș locality, on the southern and northernsides of the Olt Gorges. Triassic carbonate olistoliths were sampled in four distinct locations belonging to the Transilvanian Nappe: the Old Racoș Quarry, Olt Gorges, Tipia Racoșului Hill and Tipia Ormenișului Hill. The identified facies types include brecciated limestones with encrusting organisms and cyanobacteria, packstone-grainstone with sponges and encrusting organisms, boundstone with grainstone internal sediment, peloidal wackestone-packstone, peloidal packstone-grainstone, intraclastic grainstone-rudstone. Such microfacies characterize reefal bioconstructions or fore-reef domains located in the vicinity of shelf crest areas. They share common features with similar Wetterstein facies carbonates from Italy, Austria or Hungary. The micropaleontological assemblage indicates the Anisian-Ladinian to Carnian ages for the studied limestones, the present study bringing new data concerning the age of these carbonates. In addition, the presence of some foraminifera and dasycladalean algae are mentioned for the first time in this area. [ABSTRACT FROM AUTHOR]

In this paper we describe four new fossil associations of "reef" and "reef"-like environments of the St. Cassian Formation (Ladinian-Carnian, Dolomites, NE Italy), based on thirty thin sections from 10 "Cipit boulders" olistoliths, which slided from the Cassian platform into coeval basin sediments. The fossil associations were determined by means of microfacies analysis using point-counting and visual estimation, as well as with aid of statistical methods, based on all fractions with a biotic significance (biomorpha and microbialites). Cluster Analyses in Q-Mode were performed, coupling three algorithms and two indices. In all samples, the main components of the framework are microbialite (average of 75%), and macrofossils (average of 20%), whereas cements and allochtonous components, such as allomicrite, do not represent a significant fraction. Based on both microbialite and fossil content, Chaetetid--microencruster Association, Microbialite-microencruster Association, Dual-type Microbialite Association and Microbialite-Terebella Association, were differentiated. The palaeoenvironmental settings where the associations come from are separately discussed. Microencrusters helped determine energy and luminosity settings. Microencruster abundance and diversity, in addition to the conspicuousness of microbialite, indicate that all associations come either from a deep, or from a cryptic setting. [ABSTRACT FROM AUTHOR]

Olistostromes with calcareous olistoliths are rare components in the Ordovician successions in NW Europe and North America, having been described from only a small number of localities. One of the best exposed, but least known, is in the Garn Formation in coastal outcrops in Anglesey in northwestern Wales. Here, in the graptolite-bearing shales of the Garn Formation, there are numerous limestone olistoliths that are derived from an otherwise unknown ‘ghost’ formation whose original depositional site remains an enigma. These olistoliths contain a Baltoscandian type of conodont fauna that is otherwise unknown in Wales and England. It represents the Baltoniodus variabilis Subzone of the Amorphognathus tvaerensis Zone. Similar, but slightly older, conodont faunas are recorded from olistoliths in the Tweeddale Member of the Shinnel Formation in southern Scotland and in probable olistoliths of the Cobbs Arm Limestone in northeasternmost Newfoundland. Approximately coeval conodont faunas are present in calcareous olistoliths in the Woods Hollow Shale of West Texas and the Womble Shale in the Ouachita Mountains of Arkansas, USA. Lithological and conodont evidence indicates that the calcareous olistoliths were derived from carbonate sediments deposited in relatively shallow water. It is concluded that the study of ‘ghost’ formation olistoliths may provide otherwise unavailable but important data bearing on the marine depositional history of a particular region. [ABSTRACT FROM AUTHOR]

The Pieniny Klippen Belt (PKB) is a narrow structure delineating the boundary between the Central and Outer Carpathians. It is built of nappes stacked during the Cretaceous and Paleocene and then re-folded in the Miocene during the formation of the Outer Carpathian overthrusts. The internal structure of the PKB at the Polish/Slovakian border first formed during northward nappe thrusting processes, which were most intense at the turn of the Cretaceous to the Paleocene. A secondary factor is the change in strike of the PKB turning from W-E to WNW-ESE, associated with dextral strike-slip faulting in the Carpathian basement (North-European Platform). These NNW-SSE oriented strike-slip fault zones, broadly parallel to the Teisseyre-Tornquist Zone, are responsible for the segmentation of the down-going plate, which influenced the subduction and collision between the North-European Platform and the Central Carpathian Block. Among them, the most important role was played by the Kraków—Myszków Fault Zone separating the Małopolska and Upper Silesian blocks in the Carpathian foreland. Shifts and interactions between the neighboring Pieniny and Outer Carpathian basins—during contemporaneous sedimentation and deformation—resulted in a difficult-to-define, transitional zone. Until now this zone had the rank of a tectonic unit, named “Grajcarek Unit” in Poland and “Šariš Unit” in the Slovak Republic. However, its northern boundary, often taken to represent the Central/Outer Carpathians boundary, is ambiguous. These problems are due to the spatial overlap of thrusting and gravitational flows resulting in chaotic breccias, olistoliths and olistostrome formation, which formed repeatedly and became deformed during the Maastrichtian to Early Miocene. Tectonic deformations in this area gradually vanished towards the north. This zone can therefore be defined as the Peri-Klippen part of the Magura Nappe that lacks a distinct northern tectonic limit. For this reason it is named Šariš Transitional Zone (ŠTZ). [ABSTRACT FROM AUTHOR]

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The Merfeg Formation (upper Campanian) of Central Tunisia crops out around the southwestern periclinal termination of Jebel el Kébar, near Sidi Bouzid. At its base is a massively bedded unit of locally dolomitized, sparsely fossiliferous micritic to microbioclastic limestone that contains several discrete, plurimetric mound-like bodies (lithosomes) of micritic limestone containing locally abundant rudists and corals. The lithosomes are separated laterally from one another by megabreccias and conglomerates containing clasts of similar lithology and are overlain, with sharp contact, by onlapping argillaceous pelagic limestones, within which are intercalated at least two more, somewhat thinner rudist/coral limestone units. This complex of facies is laterally equivalent to thicker, deep platform limestones of the Abiod Formation to the north and east, and to restricted carbonate platform facies of the Berda Formation to the south and west. The lithosomes have previously been interpreted as in situ downslope mudmounds that became capped by rudist and coral formations, cemented, and then surrounded by erosively emplaced debris flows. However, our detailed studies of rudist orientations imply variable and in some cases relatively high angles of bedding within the lithosomes with respect to the regional dip of the host strata. Such steep inclinations of internal bedding are unlikely to have been primary. Accordingly, we propose an alternative interpretation that the lithosomes were platform-derived olistoliths, emplaced along with the associated debris flow deposits. Micritic beds, neighbouring the olistoliths are of variable thickness and contain rare large inoceramids and randomly oriented rudists, as well as locally developed microbioclastic beds with planar and small-scale swaley cross stratification. These micritic and microbioclastic beds are, by contrast, interpreted as primary (i.e., non-olistostromal) slope deposits. Whether the proposed catastrophic collapses of the original platform margin were induced by sea-level fall or seismically triggered (or a combination of the two) remains uncertain. [ABSTRACT FROM AUTHOR]

This paper presents a detailed lithostratigraphic investigation carried out in the Bucegi Massif, a mountainous zone from the southern part of the Eastern Carpathians. The study focused on the 50-70 m thick succession of four conglomerate units associated with olistoliths, intercalated in the upper part of the Babele Sandstone Member (the uppermost lithostratigraphic unit of the Albian Bucegi Conglomerate Formation). The conglomerate beds succession stands for the uppermost strata of the thick Bucegi conglomeratic accumulation. All the four conglomerate bodies are stratiform and continuous for almost two kilometers, and show mainly constant lithofacies features on wide areas. The study emphasizes two large-scale trends of high implication on depositional interpretation. The reduced areal extension of the basal conglomerate unit, compared with the larger extension area of the overlying units 2, 3 and 4, is one of the features with genetic significance. Another remarkable characteristic is the lateral passage from the single thick conglomerate units 2, 3 and 4, to conglomerate units alternating with sandstones beds. Another remarkable characteristic is the northwards amalgamation of the conglomerate units 1, 2, 3 and 4 into a single body, named in this paper the Conglomerates with Olistoliths. [ABSTRACT FROM AUTHOR]

Abstract: Comparative research carried out within two different basins, one in the Carpathians of Poland (Late Jurassic to Early Miocene) and another in the Apenninic-Maghrebian mountain chain of Sicily (Triassic-Miocene), indicate significant similarity not only in their evolution but also in the sedimentary features of horizons with olistoliths. The olistolith-bearing units are genetically related to stages of tectonic evolution and are independent of the size of the basins and of duration of these stages. However, the observed differences in composition and size of olistoliths suggested, among the others relationship with the size of source areas and thickness of their sedimentary cover. [Copyright &y& Elsevier]