Amal Zouicha , Jamal El Kabouri , Roland Nádaskay , Tariq Zouheir , Hafid Saber , Ahmed El Attari , Khadra Zaid
{"title":"Tectono-sedimentary evolution of the Senhaja Basin (Western Meseta, Morocco) and its implication for understanding the late Variscan tectonic processes","authors":"Amal Zouicha , Jamal El Kabouri , Roland Nádaskay , Tariq Zouheir , Hafid Saber , Ahmed El Attari , Khadra Zaid","doi":"10.1016/j.pgeola.2025.101133","DOIUrl":"10.1016/j.pgeola.2025.101133","url":null,"abstract":"<div><div>During the final stage of the Variscan Orogeny, a series of intermontane basins developed along the present-day northwestern margin of Africa, predominantly within the Western (Moroccan) Meseta. Among them, the Senhaja Basin, located in the eastern Jebilet Massif, plays a key role in interpreting diachronous evolution of those basins. Whilst traditionally considered to have formed synchronously under similar geodynamic conditions, recent evidence suggests a more complex and diachronous development.</div><div>The depositional environment of the Senhaja Basin is dominated by a fluvial system, characterized by a diversity of facies ranging from the alluvial fans in its proximal part to lacustrine deposits in its distal part. The alluvial-fan gravels feature the coarsest material deposited within the Senhaja Basin.</div><div>Integration of sedimentological and structural data supports the interpretation of the Senhaja Basin as a pull-apart basin formed in response to NE–SW compression, accompanied by localized NW–SE extension. Comparative analysis with other Late Paleozoic basins in Morocco reveals the existence of two distinct generations of basins that evolved diachronously under varying tectonic regimes–ranging from compressional to extensional settings–whilst exhibiting similarities in sedimentary infill. These findings contribute to the broader discussion on the geodynamic evolution of late orogenic basins in the Moroccan Meseta and their implications for Late-Variscan tectonic reorganization.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101133"},"PeriodicalIF":1.3,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dissolution as the origin of soft-sediment deformation structures in the Upper Cretaceous of the Noumerat area (Oued Mya Basin, Algerian Sahara)","authors":"Mostapha Benzina , Abdelmalik Draoui , Małgorzata Pisarska-Jamroży , Hocine Guerradi , Hakim Hebib , Safa Maache","doi":"10.1016/j.pgeola.2025.101134","DOIUrl":"10.1016/j.pgeola.2025.101134","url":null,"abstract":"<div><div>This study presents the first evidence of soft-sediment deformation structures (SSDS) within Upper Cretaceous lagoonal deposits of the Noumerat area, formed as a result of dissolution processes. Sulphates, particularly anhydrite, are well known for their susceptibility to karstification, with dissolution commonly reported as the origin of collapse breccia. However, this research introduces not only as the origin of breccia but also as a trigger for a variety of SSDS. These deformation features are primarily associated with the dissolution of anhydrite in Noumerat sedimentary succession, located on the Mzab Plateau in the Northern Algerian Sahara. As the anhydrite dissolved, the overlying claystones subsided into collapse troughs, accompanied by lateral sliding, forming distorted structures such as dome-like folds, water-escape structures, and slump structures. Furthermore, the presence of faults and cracks within the anhydrite layers significantly accelerated dissolution, promoting the formation of breccia fragments within the karst system. This underscores the chemical instability and rapid dissolution of anhydrite. The presence of secondary gypsum-bearing claystones, along with evidence of unconformity, and unconformities further supports this interpretation.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101134"},"PeriodicalIF":1.3,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Aspects of the deglaciation of the Lochaber Glacial Lakes area, western Scottish Highlands","authors":"J. Douglas Peacock , James Rose","doi":"10.1016/j.pgeola.2025.101131","DOIUrl":"10.1016/j.pgeola.2025.101131","url":null,"abstract":"<div><div>This paper examines the landforms and sediments in the area of the Lochaber Glacial Lakes in order to evaluate the process, pattern and timing of Late Devensian glaciation and ice wastage in that part of northwestern Scotland. Detailed evidence is provided for a number of critical areas including the Roy-Spey watershed region, the Allt Chonnal valley, the Glen Turret Fan and Moraine, the valley side fans of the upper and middle Roy valley and Glen Gloy. The work is based on field evidence and includes moraine ridges, fan landforms and sediments, along with the results of varve analyses from the Roy and Laggan valleys published elsewhere. The results suggest that, apart from some small corrie glaciers at the south side to the Roy-Spey watershed, much of the area was deglaciated following the Western Ross Readvance (<em>c.</em> 15.4–15.8 cal ka BP), prior to glaciers of the Loch Lomond Readvance (<em>c.</em> 12.9–11.7 cal ka BP) reaching the well-defined limits that held back the glacial lakes. The process of ice wastage within Glen Roy, from the Wester Ross Readvance, involved ice-marginal fluctuations, minor readvances and the formation of a pro-glacial lake related to the col at the Roy/Spey watershed. It is also proposed that many of the fans that occur along the sides of Glen Roy are of subaerial origin formed by paraglacial processes, rather than as subaquatic lake deltas.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101131"},"PeriodicalIF":1.3,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"First report of neosuchian remains in Aptian–Albian marine deposits of southeastern France","authors":"Jeremy E. Martin , Romain Jattiot","doi":"10.1016/j.pgeola.2025.101132","DOIUrl":"10.1016/j.pgeola.2025.101132","url":null,"abstract":"<div><div>The European fossil record of crocodylomorphs during the Cretaceous is indubitably skewed towards the lowermost and uppermost strata. Neosuchian remains from the Aptian–Albian interval are exceptionally rare in marine deposits globally. Yet, they potentially hold important information for understanding the phylogenetic interrelationships of several neosuchian lineages. Here, we assign a single squamosal to cf. Pholidosauridae and some postcranial elements to Neosuchia indet. from Aptian and Albian marine deposits in southeastern France. Although it is presently impossible to ascertain the continental <em>versus</em> marine origin of the specimens, their rare occurrence calls for future investigations of the diversity and interrelationships of neosuchians during the mid-Cretaceous.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101132"},"PeriodicalIF":1.3,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A night at the opera: the prestigious fate of green fluorite from the Voltennes mine, la Petite-Verrière, France","authors":"Vincent Thiéry","doi":"10.1016/j.pgeola.2025.101130","DOIUrl":"10.1016/j.pgeola.2025.101130","url":null,"abstract":"<div><div>2025 marks the 150th anniversary of the opening of the famous Opéra Garnier in Paris, France. This monument has been decorated with a wide range of various ornamental stones and marbles. One of them, namely green fluorite, or fluorspar, has been used in a unique way, as carved balusters and decorative plaques. This fluorite was exploited in the first French fluorite mine, Voltennes, opened in 1861 and located in the Morvan area. Within a system of seven veins, the main one (more than 2 km long) yielded massive green fluorite only, strong enough to be carved for decorative purposes. Abandoned since the early 1980's, the mining works strongly affected the landscape and offer an interesting, open-air example of vein mining techniques. Green fluorite in itself offers also a unique example of the durability of such ornamental stones.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101130"},"PeriodicalIF":1.3,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Benjamin T. Weston , Steven C. Sweetman , Jake Kean , Charles Wood , David M. Martill , Roy E. Smith
{"title":"A new multituberculate (Mammalia, Allotheria) from the Lulworth Formation (Cretaceous, Berriasian) of Dorset, England","authors":"Benjamin T. Weston , Steven C. Sweetman , Jake Kean , Charles Wood , David M. Martill , Roy E. Smith","doi":"10.1016/j.pgeola.2025.101128","DOIUrl":"10.1016/j.pgeola.2025.101128","url":null,"abstract":"<div><div>A new genus and species of plagiaulacid multituberculate (Mammalia, Allotheria, Multituberculata) is described from the Cherty Freshwater Beds, Warbarrow Tout Member of the Lower Cretaceous Lulworth Formation of the Purbeck Group, Dorset, United Kingdom. The new taxon is represented by a complete, well preserved left dentary containing the incisor, p2–4, with alveoli for m1–2. This new specimen is the most complete multituberculate material yet recovered from the Purbeck Group. It is also the first mammal to be recovered from the so-called ‘Flint Bed’ (DB97).</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101128"},"PeriodicalIF":1.3,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Olev Vinn , Anna Madison , Mare Isakar , Magdy El Hedeny , Abdullah A. Alkahtane , Saleh Alfarraj
{"title":"A new modern Hydrolithon-like coralline red alga from the Upper Ordovician of Estonia","authors":"Olev Vinn , Anna Madison , Mare Isakar , Magdy El Hedeny , Abdullah A. Alkahtane , Saleh Alfarraj","doi":"10.1016/j.pgeola.2025.101127","DOIUrl":"10.1016/j.pgeola.2025.101127","url":null,"abstract":"<div><div><span><span><span>A new genus and species of encrusting fan-shaped calcareous coralline </span>red algae have been described from the lower Katian of Estonia. The </span>fossils occur on the shell of the brachiopod </span><em>Porambonites</em> as a crust consisting of radial rows that systematically bifurcate, forming secondary rows that further divide into two distinct structures. The exposed surface of the rows is nearly flat and uniformly perforated with single or double rows of large, circular pores. <em>Antiquifosliella tinnae</em><span> gen. et sp. nov. stands out among other Ordovician red algae due to its large pores, which may have had a dual function. These pores were most likely involved in both gas exchange and reproduction. </span><em>A. tinnae</em><span> gen. et sp. nov. most likely belongs to the stem group of Corallinaceae<span>, though it may also represent an early lineage within the </span></span><em>Hydrolithon</em> group. In the latter case, <em>Hydrolithon</em><span> is a classical “living fossil” showing only a little morphological evolution since the Late Ordovician. The discovery of true Corallinaceae from the Upper Ordovician proves the early Paleozoic origin of the group that was previously considered to be late Mesozoic.</span></div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101127"},"PeriodicalIF":1.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Olev Vinn , Imad Bouchemla , Madani Benyoucef , Magdy El Hedeny , Mansour I. Almansour , Saleh Alfarraj
{"title":"First record of serpulid aggregations and possible serpulid reefs from the Aptian (Cretaceous) of Algeria","authors":"Olev Vinn , Imad Bouchemla , Madani Benyoucef , Magdy El Hedeny , Mansour I. Almansour , Saleh Alfarraj","doi":"10.1016/j.pgeola.2025.101126","DOIUrl":"10.1016/j.pgeola.2025.101126","url":null,"abstract":"<div><div>First serpulid aggregations have been described from the Cretaceous of Africa. The serpulid species <em>Parsimonia</em> cf. <em>antiquata</em> formed fan-shaped small aggregations up to 25 cm in diameter. The serpulids are not preserved <em>in situ</em><span><span>, and most of the material may have been derived from nearby larger serpulid reefs. The serpulid reefs presumably occurred in a lagoon or marginal marine environment. The Algerian serpulid accumulations resemble more serpulid limestones in their low faunal diversity than modern serpulid reefs with diverse associating fauna. The lagoons often have muddy or sandy bottoms where the serpulid aggregations could have been the only large hard substrates for larvae to settle. The restricted number of suitable substrates may have supported the growth of aggregations. Rich suspended food resources also likely enhanced the growth of serpulid reefs in the </span>Aptian of Algeria.</span></div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101126"},"PeriodicalIF":1.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Review of Oxfordian (Upper Jurassic) sequence stratigraphy of England (Yorkshire to Dorset) and a comparison with the North Sea Basin","authors":"John K. Wright","doi":"10.1016/j.pgeola.2025.101125","DOIUrl":"10.1016/j.pgeola.2025.101125","url":null,"abstract":"<div><div>A critical investigation is made of the unconformities reportedly present in Oxford Clay Formation and Corallian Group (Jurassic, Oxfordian) strata in central and southern England. A revised cross-section through strata belonging to the coeval Coralline Oolite Group and Upper Calcareous Grit and Ampthill Clay formations of the Tabular Hills, North Yorkshire is used to show the lateral extent of unconformities within these strata. There is definite correlation of only two of these unconformities present in Yorkshire with similar erosive episodes in the equivalent strata in southern England. The extent to which the sequences of strata delimited by these unconformities can be correlated with sequences defined in the North Sea Basin is discussed. The tectonic nature of the unconformities is evident, as there was not a simple drop in relative sea-level causing erosion. Erosion occurred down to deeper levels in certain areas, this being caused by differential uplift. The reasons for this phenomenon are still to be determined.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101125"},"PeriodicalIF":1.3,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New records of ammonites from the Lower Bajocian (Middle Jurassic) of England and Italy","authors":"Robert Chandler , Stefano Cresta","doi":"10.1016/j.pgeola.2025.101117","DOIUrl":"10.1016/j.pgeola.2025.101117","url":null,"abstract":"<div><div><span>The rare ammonite genus </span><em>Bajocia</em> is reported, as <em>Bajocia *farcyi</em><span> Brasil, for the first time from the Middle Jurassic<span>, Lower Bajocian Humphriesianum Zone, Romani Subzone of Dorset, UK. </span></span><em>Bajocia paiardinii</em> Chandler and Cresta sp. nov. is erected from the Humphriesianum Zone, uppermost Romani or lowest Humphriesianum Subzone of Monte Nerone, Apennines, Italy. The taxonomic and stratigraphical position of the genus is considered and possible evolutionary routes are suggested. The genus is likely to have evolved in the Tethys–Panthalassa Realm or southern Mediterranean–Caucasian Subrealm. Leptosphinctids, the earliest Perisphinctidae probably originated from Western Tethyan Stephanoceratidae.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"136 5","pages":"Article 101117"},"PeriodicalIF":1.3,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}