bluuebunny/crossref_metadata_2025_split huggingface dataset:
First record of Permian conodont“jinogondolella”cf.altaduensisfrom the Midhnab Member, Khuff Formation, Saudi Arabia
Authors: Nicora Alda , Vaslet Denis , Le Nindre Yves-Michel 
Published: October 2021

ABSTRACTA single specimen of conodont is described for the first time from outcrops of the Khuff Formation in central Saudi Arabia. The specimen was recovered from 22 samples that were located in the maximum flooding intervals of the Khuff Formation and specifically processed for conodont research. The sample originated from the maximum flooding interval located at the lower part of the Midhnab Member of the Khuff Formation, at Jabal al Murayrah in the Ad Darma’ quadrangle. The conodont occurs in reworked lithoclastic and bioclastic calcarenites, secondary sparitized, as a single broken and corroded specimen, which belongs to the genus Mesogondolella (Jinogondolella) and is tentatively conferred to the species “Jinogondolella” cf. altaduensis. The conodont is associated with broken pieces of fauna including bivalves, gastropods, echinoids, brachiopods and bryozoans, as well as foraminifers and dasycladacean algae. This genus is rarely encountered in the open-marine deposits of the Tethyan platforms, where it appeared preferentially in semi-restrictive (saline) basins. A Late Capitanian age is interpreted for some species of the genus Jinogondolella in America (Texas), China and Oman, but this age interpretation is not firmly established for the Midhnab Member of the Khuff Formation. Also due to the reworked nature of the horizon that yielded this condont, the specimen is not considered to be age-indicative.
New records and new taxa of Permian brachiopods from the Khuff Formation, Midhnab Member, central Saudi Arabia
Authors: Angiolini Lucia , Vaslet Denis , Le Nindre Yves-Michel , Zarbo Miriam 
Published: October 2021

ABSTRACT
Brachiopods are described for the first time from outcrops of the lower part of the Midhnab Member of the Khuff Formation in central Saudi Arabia. The very rare fauna discovered includes Kotlaia sp. ind. of the order Orthida and Omanilasma husseinii n. gen. n. sp. of the order Terebratulida. Besides this new taxon, another new species Omanilasma desertica n. gen. n. sp. from the Khuff Formation of Interior Oman is here erected. The brachiopods were collected from an open-marine horizon and are associated with nautiloids, bactritids, bivalves, foraminifers, algae, and ostracods. A probable Late Permian age is assigned to the lower part of the Midhnab Member based on foraminifers. The brachiopods are compared to similar faunas from the Middle Permian Khuff Formation of Interior Oman, Amb Formation of Salt Range (Pakistan) and Rat Buri Limestone of Southeast Thailand.
Review of Middle East Paleozoic plate tectonics
Authors: Ruban Dmitry A. , Al-Husseini Moujahed I. , Iwasaki Yumiko 
Published: October 2021

ABSTRACTThe Paleozoic Middle East terranes, neighboring the present-day Arabian and Levant plates, are shown by most authors to consist of ten major tectonic units: (1 and 2) the Helmand and Farah terranes of Afghanistan, southwest Pakistan and southeast Turkmenistan; (3 to 6) the Alborz, Central Iran (Lut, Yazd and Tabas) and Sanandaj-Sirjan terranes of Iran, and Northwest Iran (possibly extending into eastern Turkey); (7 and 8) the Pontides and Taurides terranes of Turkey; and (9 and 10) the Greater and Lesser Caucasus terranes between the Caspian and Black seas (Armenia, Azerbaijan, Georgia and southwest Russia). Published plate-tectonic reconstructions indicate that all ten terranes may have broken off from either: (1) the Gondwana Supercontinent in the mid-Silurian as part of the Hun Superterrane; or (2) the Pangea Supercontinent during the mid-Permian - Triassic as part of the Cimmeria Superterrane. To the north of Gondwana and Pangea, three successively younger Tethyan oceans evolved: (1) Proto-Tethys (Cambrian - Devonian); (2) Paleo-Tethys (mid-Silurian - Mesozoic); and (3) Neo-Tethys (mid-Permian - Cenozoic).Two regional Paleozoic unconformities in the Arabian Plate are generally linked to major regional-scale structural events, and commonly correlated to the Caledonian and Hercynian orogenies. These orogenies took place many thousands of kilometers away from the Arabian Plate and are considered unlikely causes for these unconformities. Instead, the breakaway of the Hun and Cimmeria superterranes are considered as alternative near-field tectonic sources. The older unconformity (middle Paleozoic event), represented by a mid-Silurian to Middle Devonian hiatus in North Arabia (Iraq and Syria), reflects an episode of epeirogenic uplift, which might be related to the mid-Silurian rift of the Hun Superterrane. The younger mid-Carboniferous Arabia-wide angular unconformity involved compressional faulting and epeirogenic uplift, and might be related to the earliest phase of subduction by the Paleo-Tethyan crust beneath Cimmeria (Sanandaj-Sirjan and nearby regions) before it broke off. Based on our review and regional considerations, we assign the Helmand, Farah, Central Iran, Alborz, Sanandaj-Sirjan, Northwest Iran, Lesser Caucasus, Taurides and Pontides to Cimmeria, whereas the Greater Caucasus is considered Hunic.
Early Silurian (Llandovery) graptolites from central Saudi Arabia: First documented record of Telychian faunas from the Arabian Peninsula
Authors: Jan Zalasiewicz , Mark Williams , Merrell Miller , Alex Page , Edward Blackett 
Published: October 2021

ABSTRACTGraptolites from three shallow core holes penetrating lower Silurian strata in central Saudi Arabia identify rocks of mid Aeronian and early Telychian age. The graptolites comprise Campograptus undulatus?, C. lobiferus?, Lituigraptus convolutus, Metaclimacograptus bohemicus, Neolagarograptus rickardsi, Normalograptus? aff. scalaris, cf. Paradiversograptuscapillaris,Petalolithusminor,P.praecursor,P.ovatoelongatus?, Pristiograptus regularis sl, Pseudorthograptus insectiformis, Pseudoretiolites perlatus? and Torquigraptus? decipiens, which identify the mid Aeronian convolutus Biozone, and Monograptus bjerreskovae, Monograptus ex gr. marri, Paradiversograptus runcinatus?, Petalolithus cf. altissimus, Pristiograptus renaudi, Stimulograptus becki and S. halli?, which indicate the early Telychian guerichi Biozone. The graptolite faunas are generally of low diversity, with most levels yielding between one and three species, occasionally rising to as many as seven species. The palaeogeography of the depositional basin, coupled with the low diversity and the abundance of Pristiograptus and Normalograptus species, suggests a marine-shelf setting. This is also indicated by the common occurrence of benthic shelly fossils, including articulated bivalves and gastropods. In general, the graptolite faunas are of much lower diversity than contemporaneous marine assemblages from the British Isles or the Czech Republic, and probably represent a graptolite biotope of “cratonic invaders.” Graptolites are very well preserved, displaying detail of fusellar banding (growth increments) and perhaps ultrastructure.
Design of a P-wave seismic vibrator with advanced performance
Authors: Wei Zhouhong 
Published: October 2021

ABSTRACT
For optimal seismic imaging, the vibroseis method requires the vibrator to generate synchronous, repeatable sweeps over a broad frequency range and output the ground-force energy with minimum harmonic distortion. This requires re-evaluating each element of the vibrator system to ensure that it contributes to the success of the method. Key factors that cause the vibrator to suffer from severe harmonic distortion are fluctuations in the hydraulic power supply pressure, flexing of the baseplate, coupling or loading between the baseplate and the ground, nonlinear servo-valve flow-pressure characteristics, and servo-valve characteristics near null. This paper examines these factors and describes the design of a new P-wave vibrator by ION (previously I-O) to improve seismic resolution. Experimental results demonstrate that the newly designed vibrator dramatically reduces harmonic distortion in the ground-force signal under various coupling conditions, particularly on hard and uneven ground. With the high-frequency controller and Pelton DR valve, a broad-band sweep frequency is achieved. Cavitations in the supply pressure, a long-standing problem in vibrator mechanics, are almost completely eliminated.
Outcrop sedimentology of the Natih Formation, northern Oman: A field guide to selected outcrops in the Adam Foothills and Al Jabal al Akhdar areas
Authors: Homewood Peter , Razin Philippe , Grélaud Carine , Droste Henk , Vahrenkamp Volker , Mettraux Monique , Mattner Joerg 
Published: October 2021

ABSTRACT
This field guide describes eleven outcrops of the Natih Formation in the Al Jabal al Akhdar-Jabal Shams and Adam Foothills areas, not far from Nizwa, at the foot of the Oman Mountains. The outcrops have been chosen for their accessibility, as well as for the fairly complete picture of the Natih Formation, which they piece together. To visit all eleven outcrops requires several days and the use of 4-wheel-drive vehicles, but the locations offer no serious physical difficulty, nor long hiking, to gain access.
The outcrop descriptions follow in stratigraphic order from the lower to the upper Natih members, roving back-and-forth across the outcrop area. Much of the detailed account of the sedimentology and stratigraphy of the Natih that has been used as the basis of this field guide, has been given previously by van Buchem et al. (1996, 2002), Grélaud (2005), Schwab et al. (2005) and Grélaud et al. (2006). The observations and interpretations given here come in part from those studies, but this paper is also largely the product of a subsequent project that was carried out for the Fahud Studies Team of Petroleum Development Oman (PDO), to provide detailed sedimentology and high-resolution sequence stratigraphy of the Natih Formation for further development of the Fahud field (Homewood et al. 2006). In this respect, this field guide is not so much intended to be an original contribution in terms of the science concerning the Natih Formation. The intent is to provide the ways-and-means for all to gain a first-hand personal understanding of the rocks we have enjoyed working on.
Following the outcrop descriptions, a general section provides a discussion on facies and facies associations in terms of the constraints of sequence stratigraphy, sea-level change and clay influx on the carbonate factory. With the incorporation of limited subsurface seismic and well data, geobodies and depositional assemblages, the three-dimensional objects that form the stratigraphic packages at outcrop and seismic scales, respectively, are also discussed. Facies are thus interpreted not only in terms of depositional environments, but are also placed within both geometrical (geobody, depositional assemblage) and sequence-stratigraphic frameworks.
In the conclusion, it is argued that a deeper understanding of the Natih Formation has been gained by comparison of outcrop data with subsurface data, and by contrast with modern analogs. The detail required to apply what was learned from outcrop to the nearby subsurface, in a practical manner (but also properly to reconstruct the successive Natih scenarios), requires building several facies models. This is in contrast to giving a single composite picture of Natih facies distribution in space and time, under one single facies model.
Facies in the Unayzah Formation and the Basal Khuff Clastics in subsurface, northern Kuwait
Authors: Tanoli Saifullah Khan , Husain Riyasat , Sajer Abdul Aziz 
Published: October 2021

ABSTRACT
This is the first reporting of the Unayzah Formation from a northern Kuwait deep well where a 304 ft of core was cut in the upper part of the formation. The core consists of about 202 ft of the Unayzah Formation, 74 ft of the Basal Khuff Clastics and 28 ft of the Khuff Formation. Within the Unayzah Formation six major lithofacies were interpreted: (1) high-angle cross-bedded sandstone; (2) fine-grained sandstone; (3) normally graded coarse pebbly sandstone; (4) medium- to fine-grained sandstone and siltstone; (5) red mudstone and siltstone; and (6) black shale. In the Basal Khuff Clastics, four lithofacies were recognised: (1) fine- to medium-grained clean sandstone; (2) muddy bioturbated sandstone and siltstone; (3) dark grey to black carbonaceous shale with sand interbeds; and (4) interbedded sandstone, siltstone and dolomite. These lithofacies can be subdivided into four broad palaeoenvironments; ?eolian, braided fluvial, flood plain, and coastal plain. The possible eolian facies are represented by high-angle, cross-bedded sandstones of likely dune affinity. Braided fluvial facies consist of pebbly sandstones, which may grade normally to fine-grained sandstone and siltstone. Flood-plain environments are interpreted for the red mudstone, shale, and siltstone, which consist of prominent root casts and other subaerial exposure features. This facies is prominently repeated three times within the cored zone. Coastal plain environments are represented by tidal channels consisting of fine-grained and clean sandstone, crevasse splay and interfluve sediments consisting of bioturbated sandstone, siltstone and shale and by dark grey to black shale of coastal marsh in origin.
The core did not cover the lower contact of the Unayzah Formation. The upper contact of the formation with the Basal Khuff Clastics is placed at the top of the last oxidised red zone. Due to the limited palynofloral information, the age of the cored interval is not definitive but most likely is of Kazanian to Tatarian (Wordian to mid-Wuchiapingian). The Basal Khuff Clastics and the overlying Khuff Formation is equivalent to the OSPZ6 biozone and the Unayzah Formation could be in part equivalent to the OSPZ5 biozone. The sediments belonging to the Basal Khuff Clastics mark the onset of a major transgression that developed into a platform where carbonates of the overlying Khuff Formation were deposited.
Structural and tectonic evolution of the Jabal Sumeini – Al Ain – Buraimi region, northern Oman and eastern United Arab Emirates
Authors: Searle Michael P. , Ali Mohammed Y. 
Published: October 2021

ABSTRACT
Four main Late Cretaceous and Tertiary phases of crustal shortening and thrust-related deformation are recognised in the northern Oman Mountains, each phase ending with a regional unconformity throughout the Oman Mountains and the UAE foreland. The earliest is the major thrust emplacement of the Semail Ophiolite, and underlying Haybi, Hawasina and Sumeini duplexes from NE to SW onto the depressed northeastern continental margin of the Arabian Plate during the Cenomanian to Campanian-early Maastrichtian (D1). A prominent widespread unconformity that places Maastrichtian Qahlah Formation laterite, sandstones and conglomerates and Simsima Formation rudist - Acteonellid gastropod limestones over all underlying allochthonous units is recognised throughout the Oman Mountains. SW-verging folds and thrusts in Triassic to Cretaceous carbonate slope facies rocks exposed in Jabal Sumeini (Sumeini Group and Hamrat Duru Group) have been emplaced over uppermost Cretaceous Juweiza Formation conglomerates at the highest level of the Aruma foreland basin. These Sumeini D1 structures are abruptly truncated by an unconformity, above which are Middle Maastrichtian beds showing up to 95% ‘death assemblage’ rudists and gastropods just below the Cretaceous – Tertiary boundary (top of Simsima Formation). A second deformation event (D2) affected the Simsima Formation and underlying Sumeini Group, Hamrat Duru complex and Semail Ophiolite rocks. This phase shows gentle folding about NW-SE fold axes (e.g. Jabal Rawdah), along a similar trend to the Late Cretaceous D1 event. This trend is also parallel to a regional set of NW-SE aligned fractures in the UAE foreland. A major angular unconformity occurs beneath the Upper Palaeocene – Eocene shallow-marine limestones (Umm Er Radhuma, Rus and Dammam formations). Many foreland jabals in eastern Abu Dhabi (Jabals Qatar, Malaqet, Mundasa) show gentle post-Eocene folding formed during the third stage of crustal shortening (D3). The large pericline of Jabal Hafit is a double-plunging, east-verging box fold that formed after deposition of the Oligocene Asmari Formation limestones and Miocene Fars Formation gypsum and clays, the youngest beds affected by the fold. This Late Miocene – Pliocene phase of crustal shortening (D4) is the youngest phase of deformation in the eastern Al Ain-Buraimi region.
The Wadi ad Dawasir “delta”, central Saudi Arabia: A relative sea-level fall of Early Bathonian age
Authors: Énay Raymond , Mangold Charles , Alméras Yves , Hughes Geraint Wyn ap Gwilym 
Published: October 2021

ABSTRACT
The fluvial and deltaic deposits formerly described as the Wadi ad Dawasir “delta” have been reinterpreted on the basis of a new examination of biostratigraphic data, notably ammonites and brachiopods studied by the authors and nautilids studied by the late H. Tintant (the term “delta” as used in other documents is shown here in quotes because of insufficient evidence to confirm it as a true delta). Direct dating of the fluvial and deltaic deposits is not possible in the absence of age-indicative fossils, but the entire “delta” complex can be placed in the Lower Bathonian on the basis of Bathonian ammonite and brachiopod faunas found in underlying strata, and a Lower Bathonian nautilid found in the uppermost proximal beds. An Early Bathonian age of the “delta” revises the Middle Callovian age assumed by previous authors based on their admittedly lithostratigraphic correlation with marine strata of the Dhruma Formation. The Early Bathonian age is consistent with the alternative interpretation, which correlates the “delta” with the discontinuity in the marine sequence between units D5 and D6 of the Dhruma Formation, with a stratigraphic gap of Lower (in part) and Middle Bathonian. The nautilids and brachiopods from above and “apparently at the front” of the “delta” together with the ammonites, nautilids, brachiopods and calcareous nannoplankton from units D6 and D7, indicate a complete sequence from the Upper Bathonian (unit D6) to Upper Callovian (units T2 and T3 of the Tuwaiq Mountain Limestone) with transgressive overlap of the “delta” during Middle and Late Callovian. The Wadi ad Dawasir “delta” is here interpreted as resulting from a limited relative sea-level fall, causing progradation of a shelf deltaic wedge over the downlap surface associated with the D5–D6 discontinuity. Similar deltaic or/and paralic deposits have been described in the Lower Bathonian of northern Sinai, presumably of the same age, Negev and in the Bathonian of southern Tunisia, which indicate an event of wide extent (eustatic, climatic or tectonic) along the northern Gondwanan margin.
Evolution of fractures in a highly dynamic thermal, hydraulic, and mechanical system - (II) Remote sensing fracture analysis, Jabal Shams, Oman Mountains
Authors: Holland Marc , Saxena Nishank , Urai Janos L. 
Published: October 2021

ABSTRACT
Extensive, very high quality outcrops on the southern flank of Jabal Shams, Oman Mountains, expose the complex fracture and fault network of an exhumed high-pressure cell. Veins are filled with white calcite in grey host rock, allowing 0.7 meter-resolution mapping based on satellite image interpretation, followed by ground-truthing with detailed field observation in selected areas. From Quickbird and Landsat data, a model was developed using interpreted 562 faults and 145,000 fractures in an area of 31 km2; the area of a typical 3-D seismic survey but with one hundred times higher resolution. Four generations of veins, with strikes of 130°, 000°, 090° and 045°, are overprinted by normal faults with wide cemented damage zones and offsets up to 500 m. Veins are generally a few 10s of meters long, and lack signs of strong mechanical interactions such as curving or abutting. This suggests a restoration of the bulk strength during the formation of the joints, and an anticlockwise rotation of permeability anisotropy during progressive fracturing. The spatial density of all cemented fractures is rather homogenous, but the spatial density within individual joint sets is heterogeneous, suggesting patchy fracturing during the different evolutionary stages. A weak mechanical anisotropy, caused by the veins, affects the nucleation and evolution of the anastomosing normal fault system that overprints the cemented joints.
Refinements in biostratigraphy, chronostratigraphy, and paleogeography of the Mississippian (Lower Carboniferous) Mobarak Formation, Alborz Mountains, Iran
Authors: Brenckle Paul L. , Gaetani Maurizio , Angiolini Lucia , Bahrammanesh Maryamnaz 
Published: October 2021

ABSTRACT
Detailed sampling of limestones from the Mobarak Formation at the Abrendan and Abnak measured sections in the eastern and central Alborz Mountains, northern Iran, yielded a diverse assemblage of Tournaisian – Lower Visean (Mississippian/Lower Carboniferous) calcareous microfossils (foraminifers, algae, incertae sedis). The Abrendan locality contains Tournaisian foraminifers in the upper part of the formation that correlate to the Ivorian and upper Courceyan – lower Chadian substages of western Europe and the Kosvinsky Horizon of the Russian Platform. Brachiopods confirm a Tournaisian age for the lower part of the Mobarak, which lacks age-diagnostic calcareous microfossils. Lower Visean foraminifers at Abnak provide good correlation to the western European Moliniacian and Arundian substages and the Russian Bobrikovsky Horizon. Synthesis of foraminiferal data from this and other published reports indicates that the top of the Mobarak Formation becomes increasingly older across the Alborz to the southeast, caused most likely by Pennsylvanian (Upper Carboniferous) exposure and erosion in the south followed by a latest Pennsylvanian – Early Permian transgression from the north. The microbiota at both sections and the macrofossils at Abrendan show close affinity to the warm-water Paleo-Tethyan Ocean, seemingly contradicting Early Mississippian paleomagnetic reconstructions placing the Alborz region at 45–50° South latitude. The discrepancy is not resolvable at this time, but the answer may lie in the circulation of Paleo-Tethyan currents to the south along the Gondwanan shelf, rather than to repositioning the Alborz region to the northern side of the Paleo-Tethyan Ocean.