Ancient Sea Research Articles

Biotic composition and microfacies distribution of Upper Triassic build-ups: new insights from the Lower Carnian limestone of Lesno Brdo, central Slovenia

The architecture and composition of Middle to lower Upper Triassic platforms is often obscured by dolomitization. Hence, comparatively little is known about their architectures compared to their size and geographic extent. An active quarry near Lesno Brdo (central Slovenia) offers an excellent exposure of Lower Carnian (Julian) massive limestone, which is diagenetically little altered. A detailed microfacies analysis along a 15.5-m log revealed the presence of three facies types: fine-grained limestone as a groundmass, blocks and globular masses of sponge-microbialite boundstone, and lens-like aggregations of polychaete (terebellid) tubes. Sponge-microbialite boundstone contains a rather small number of cosmopolitan sponge taxa, solenoporacean red algae, microproblematica, bryozoans, and a small proportion of dwelling fauna. Instead, stromatolites represent the main constituent. While some blocks appear to have truncated margins, others show mammillary-like protrusions of microbialites into the surrounding sediment, suggesting active growth of microbialite-producing organisms. Aggregations of terebellid worm tubes show a highly irregular relief, with tubes placed sub-parallel to the ancient sea floor. The presence of fibrous rim cement, crystal silt, and in some cases fragmentation of the tubes, suggest at least moderately energetic waters. Aggregations are thus interpreted as preserved in situ, but not in toto. The entire complex was probably deposited at the margin or upper slope of a carbonate platform. Although the presence of a large number of terebellids associated with microbialites boundstone may indicate some sort of environmental stress, such a stress remains to be identified.

Ko Kupe Te Tupuna

The book “The Tail of the Fish” was publised in 1968 and written by a Te Aupouri kuia, Matire Kereama (nee: Hoeft) of the far north of Aotearoa, New Zealand. I grew up with this book as my grandmother would read the stories to me at bedtime. Although my comprehension of each story was very vague and unrelatable to my life at that time, today, I find myself totally absorbed by the historical content and knowledge encapsulated in each chapter.
 I completed a Masters of Applied Indigenous Knowledge at Te Wananga o Aotearoa in 2017, entitled; Tales of the singing fish: He tangi wairua. I compsed twelve waiata (Maori songs) of which ten of the waiata was information extracted from ten chapters of the book. The other two waiata were composed specifically for my people of the Te Rarawa tribe, namely, Ahipara.
 The whakatauki “e kore e ngaro, he takere waka nui” (we will never be lost; we are the hull of a great canoe) demonstrates the amazing srength of the ancient sea voyager “Kupe” who discovered Aotearoa, New Zealand, in the deep South Pacific Ocean, Te Moana nui ā Kiwa.

Current status and future directions of Lévy walk research.

ABSTRACTLévy walks are a mathematical construction useful for describing random patterns of movement with bizarre fractal properties that seem to have no place in biology. Nonetheless, movement patterns resembling Lévy walks have been observed at scales ranging from the microscopic to the ecological. They have been seen in the molecular machinery operating within cells during intracellular trafficking, in the movement patterns of T cells within the brain, in DNA, in some molluscs, insects, fish, birds and mammals, in the airborne flights of spores and seeds, and in the collective movements of some animal groups. Lévy walks are also evident in trace fossils (ichnofossils) – the preserved form of tracks made by organisms that occupied ancient sea beds about 252-66 million years ago. And they are utilised by algae that originated around two billion years ago, and still exist today. In September of 2017, leading researchers from across the life sciences, along with mathematicians and physicists, got together at a Company of Biologists' Workshop to discuss the origins and biological significance of these movement patterns. In this Review the essence of the technical and sometimes heated discussions is distilled and made accessible for all. In just a few pages, the reader is taken from a gentle introduction to the frontiers of a very active field of scientific enquiry. What emerges is a fascinating story of a truly inter-disciplinary scientific endeavour that is seeking to better understand movement patterns occurring across all biological scales.

The Ancient Mediterranean Sea in Modern Visual and Performing Arts: Sailing in Troubled Waters by Rosario Rovira Guardiola

The Ancient Mediterranean Sea in Modern Visual and Performing Arts: Sailing in Troubled Waters by Rosario Rovira Guardiola

Oldest record of Mathildellidae (Crustacea: Decapoda: Goneplacoidea) associated with Retroplumidae from the Upper Cretaceous of NE Mexico

A new genus and species of the Mathildellidae Prebranchioplax cretacica (Crustacea: Decapoda: Goneplacoidea) is reported from shallow marine sediments of the upper Campanian Parras Shale and Cerro del Pueblo Formation (Parras Basin), Coahuila, NE Mexico. Prebranchioplax cretacica was collected from siliceous concretions associated with more abundant specimens of the retroplumid Costacopluma mexicana Vega and Perrilliat, 1989. P. cretacica bears similarities to Eocene species of Branchioplax from Japan, USA (Alaska and Washington), England, Hungary and Tajikistan as well as with Eogeryonidae (Portunoidea) species from the Upper Cretaceous of Spain and Marocarcinidae (Styracocarcinus) from Morocco. However, clear differences in the carapace frontal shape places P. cretacica in the Mathildellidae. This record represents the oldest known Mathildellidae, and along with the Retroplumidae, appear to have originated during the Late Cretaceous in ancient seas of Mexico, with a wide distribution during Paleogene times becoming restricted today to deep waters of the Indo-Pacific region and Atlantic Ocean. Comments on preservation and morphology of Costacopluma mexicana are also included. Crab specimens preserved in siliceous concretions from one locality (Entronque) show peculiar desiccation marks, and a possible model of taphonomy.

Tethyan changes shaped aquatic diversification.

The Tethys Ocean existed between the continents of Gondwana and Laurasia from the Triassic to the Pliocene. Analyses of multiple biogeographic and phylogenetic histories reveal that the subsequent breakup of the Tethys greatly influenced the distributions of many species. The ancestral Tethyan realm broke into five biogeographic provinces, including the present-day East Pacific, West Atlantic, East Atlantic, Mediterranean Sea, and Indo-West Pacific. Palaeogeographic maps illustrate the Mesozoic Atlantic opening, the Cenozoic closure of the Tethys, the Messinian Salinity Crisis, the mid-Miocene closure of the Central American Seaway, and Quaternary geological changes. Further, we consider Cenozoic sea-level changes and the formation of freshwater habitats. These reconstructions allow assessment of patterns of aquatic diversification for marine and freshwater animals, and comparison of vicariance and dispersal processes. Estimated divergence times indicate that fragmentation of the Tethys was responsible for the vicariant speciation of aquatic animals because these dates are consistent with associated tectonic events. The opening of the Atlantic Ocean during the Cretaceous is responsible for the earliest isolation between the West and East Atlantic. The mid-Miocene closure of the Tethys, which blocked global equatorial currents, appears to have isolated the Atlantic/Mediterranean Sea and Indo-West Pacific. Finally, formation of the Isthmus of Panama isolated East Pacific and West Atlantic marine organisms. Dispersals related to the Messinian Salinity Crisis and Quaternary sea-level changes influenced population structuring. Tethyan changes affected marine habitats, created new freshwater habitats, inland caves and ancient lakes along the Alps and Himalayas, and influenced anchialine caves at the edge of the ancient sea. The extensive new habitats provided opportunities for colonisation and rapid diversification. Future work should focus on testing the biological impact of the series of Tethyan changes.

Origins of Life

Charles Darwin in 1871 suggested that microbial life originated in some 'warm little pond' full of 'ammonia, phosphoric salts, heat and electricity'. In light of recent discoveries on the origin of life, Charles Darwin's theory appears prescient. In the first half of the 20th century, Alexander Oparin established the 'metabolism first' hypothesis to explain the origin of life. Aligning with this hypothesis, most scientists believe that the first forms of life evolved in the warm vents of ancient seas.

The origin and geochemical characteristics of Permian chert in the Eastern Sichuan Basin, China

Chert is widespread in Permian Maokou Formation and Wujiaping Formation of the eastern Sichuan Basin, China. Field observations in conjunction with major element, REE, and isotope analysis suggest that the chert is both biogenic and hydrothermal in origin. Further analysis indicates that hydrothermal features are more prominent in chert of the Maokou Formation, whereas chert of the Wujiaping Formation contains stronger evidence of biogenic origin. The SiO2 content of chert of the Maokou and Wujiaping formations are 80.09–97.91 and 65.52–97.76 wt%, respectively. The average Al/(Al + Fe + Mn) values are 0.35 (Maokou Formation) and 0.38 (Wujiaping Formation), and most samples are plotted in the Fe-rich section of the Al–Fe–Mn diagram. SiO2 abundance and Al/(Al + Fe + Mn) ratio analysis of chert of the Maokou and Wujiaping formations suggest a hydrothermal origin, although several samples were more indicative of biogenic origin. The average REE content of chert in both formations is low, and average REE is lower in chert of the Maokou Formation than in chert of the Wujiaping Formation. The Ce anomaly is weakly negative in the chert of the Maokou Formation (0.62) and Wujiaping Formation (0.71), whereas the average Eu value is greater in chert of the Maokou Formation than in chert of the Wujiaping Formation. The δ30Si values of chert are 0.4–1.2‰ in the Maokou Formation and 0.7–1.4‰ in the Wujiaping Formation, and these values are close to the δ30Si values of modern radiolarians. The average palaeoseawater temperatures under which the chert formed were calculated as 66 °C for chert of the Maokou Formation and 62 °C for chert of the Wujiaping Formation. These calculated temperatures are significantly higher than estimated ancient sea temperatures. These data and interpretations suggest that the chert of the Permian Maokou and Wujiaping formations were affected by volcanism and fracturing during the Permian. Seawater seeped through fractures and interacted with upwelling hot magma along basement faults, resulting in silica dissolution and the enrichment of waters from hot spots along fractures as well as the enrichment of seawater. This enrichment resulted in the mass reproduction of siliceous organisms, such as radiolarians and sponges, which were eventually deposited to form biosiliceous rocks.

Late-quaternary transgression of the White Sea as deduced from data on GIS-Based bottom relief analysis

We examine the use of geoinformation systems and relevant software applications in marine geomorphology in terms of the digital elevation model of the White Sea region. The geomorphological development of the contemporary shoreline is shown on the basis of comparing the parameters of adjacent surfaces. The technique is suggested for identifying relative tectonic deformations by determining the morphoblock division of the seabed surface. In this case, the boundaries of the time interval used in investigating the tectonic dislocations are specified indirectly by the scale coefficient of the initial digital model. This indirect relationship is determined on the basis of the well-known expression of a dependence of oscillations of a massive object in an elastic medium. By analyzing the structure of seabed relief, we determined areas with a high value of tectonic deformations for the period involved (Holocene) relative to the level of marine sedimentation. A neotectonic regionalization of the surface of the White Sea bed allowed us to identify, on the basis of statistical dependencies, large planate subhorizontal surfaces of the seabed. Upon comparing the graphical analytical information obtained with geomorphological characteristics of these surfaces, we determined four submarine terraces of an abrasion-accumulative origin and drew the corresponding boundaries within which the ancient White Sea existed over the course of the Holocene. By analyzing the position of the marine terraces, we identified a relative intensification of marine abrasion processes at a particular evolutionary stage of the water area. This is associated with a crucial marker event in the development of the White Sea water area, namely its connection with the Word Ocean in the early Holocene.

PALEOENVIRONMENTAL DISTRIBUTION OF ORDOVICIAN CALCIMICROBIAL ASSOCIATIONS IN THE TARIM BASIN, NORTHWEST CHINA

The stratigraphic and facies distribution of 20 calcimicrobial genera (including calcified cyanobacteria and associated problematic calcified microfossils) are reported for the entire Ordovician succession in the Tarim Basin in northwestern China based on examination of drill cores and 8500 thin sections from 64 wells from the Tabei, Bachu, Tazhong, and Tadong uplifts. A total of ten calcimicrobial associations are recognized in the Lower to Upper Ordovician based on taxonomic composition and distribution within four paleoenvironment types: reef (marginal and patch reef), open platform/bank (marginal and patch bank), lagoon, and tidal flat. The temporal distribution of the calcimicrobial genera closely follows changes in sedimentary environments; an extensive literature survey reveals similar relationships in much of the Paleozoic and Mesozoic. Based on their paleoenvironmental preferences, calcimicrobes can be classified into five paleohabitat types: (1) reef-adapted (Acuasiphonoria, Razumovskia, Phacelophyton , Gomphosiphon, Epiphyton, Renalcis, and Izhella); (2) open platform/bank-adapted (Subtifloria and Bevocastria); (3) both reef and open platform/bank-adapted (Bija, Apophoretella, Rothpletzella, and Wetheredella); (4) lagoon-adapted (Hedstromia, Cayeuxia, Zonotrichites, Ortonella, and Garwoodia), and (5) not only reef and open platform/bank-adapted but also tolerant of tidal flat conditions (Girvanella and Proaulopora). The occurrences of these calcimicrobes in strata not only can indicate ancient sedimentary facies but also can reveal paleoecological parameters of ancient seas, such as nutrient levels (e.g., N and P), predation pressure, and sea level, especially in strata absence of other well-studied facies fossils.

A killer tail spine likely helped this ancient sea scorpion subdue its prey

A killer tail spine likely helped this ancient sea scorpion subdue its prey

Did interaction between human pressure and Little Ice Age drive biological turnover in New Zealand?

AbstractAimTo test for simultaneous Holocene biogeographic turnover events in the New Zealand region. Specifically, we synthesize ancient DNA, radiocarbon data and archaeological data to assess the chronologies of late Holocene lineage extinction and replacement.LocationCool‐temperate coastal ecosystems of New Zealand and the subantarctic.MethodsWe present new ancient DNA and radiocarbon data for New Zealand sea lions, and synthesize existing climatic, genetic and archaeological data, to test for synchronous megafaunal extinction and replacement events. The collated data include ancient DNA sequences from over 200 ancient sea lion and penguin specimens, in addition to 150 modern genetic samples.ResultsOur temporal genetic analyses show that, following human‐driven extinction events, synchronous marine megafaunal replacement events occurred at around 1500 AD, coinciding with the Little Ice Age onset and an associated drastic human demographic decline in southern New Zealand.ConclusionsA combination of climatic and human demographic shifts likely facilitated northward expansion of subantarctic sea lion and penguin lineages, replacing extirpated mainland New Zealand marine megafauna. Broadly, the interaction between human pressure and late Holocene climatic change may explain multiple biological turnover events in the Southern Hemisphere.

Evaporation stage of paleo-saline lake in North Shaanxi salt basin China: insight from fluid inclusions in halite

Fluid inclusions within halite from the Mizhi cores in the North Shaanxi Basin were studied to restore the ancient sedimentary environment, and to discuss the material supply on this basis. Fluid inclusion analyses include fluid inclusion petrography to examine their characteristics and types, hydrogen and oxygen isotopic compositions of trapped fluids, and package play flow components. This study shows that halite recrystallization occurred in the North Shaanxi Basin from fluid mixing of fresh and brine waters during transgressions. Hydrogen and oxygen isotopic compositions of halite inclusions show that precipitation of halite was supplied by multiple provenances, including thermal fluids. The study on the fluid compositions in the Ordovician halite inclusions indicates that the ancient sea water could allow the precipitation of the potassium magnesium salt rocks at that time, but the frequent transgressions influenced the preservation of the potassium magnesium salt rocks. Therefore, using the available data, this study proposes that the deposition of the MajiagouV member in the North Shaanxi Basin was supplied by transgressive sea water and thermal fluids. In addition, the frequent transgression during the Majiagou deposition affected the preservation of the potassium magnesium salt.

How giant marine reptiles terrorized the ancient seas.

Ichthyosaurs were some of the largest and most mysterious predators to ever prowl the oceans. Now they are giving up their secrets.

Determination and Radiocarbon Dating of Marine Mollusc Fossils in Ancient Sea Shelf of Central Java Indonesia

Mollusc phylum is one of the most adaptive animal groups on Earth. They occupy and thrive in incredibly diverse habitats. Their distribution in the fossil record is equally diverse. Indonesia is one of the country with marine mollusc fossil variety, such as in the archaeological site of Sangiran, Patiayam (Ancient Muria Strait) and Grobogan – Central Java. Radiocarbon Dating is the method for dating analysis using 14C. By measuring 14C content, we can estimate how long ago the fossils died. Radiocarbon dating is an extremely useful technique for determining the ages of geological materials (that have some organic-derived carbon in them). Field sampling had found variety of marine mollusc fossils such us 1) Sangiran: Dosinia sp., Telescopium telescopium, Anadara sp., and Dosinia insularum; 2) Patiayam (Ancient Muria Strait): Pseudodon vondenbuschianus, Elongaria orientalis, Conus (Pionoconus) sp., Ampullina bandongensis, Anadara pilula and Filopaludina javanica; 3) Grobogan: Antigona chemnitzii, Cultelus dilatatus, Plotia scabra and Tibia modesta. Mollusc fossils sample was analysed using Accelerator Mass Spectrometer (AMS) radiocarbon system. It is a good method for dating specific samples. The result showed that Sangiran as an ancient deepsea has fossils age 38710 – 31947 years, then Patiayam (Ancient Muria Strait) with fossils age 26248 – 11994. Mollusc fossils from Grobogan was the youngest area has fossils age 25692 – 6479 years.

下切谷研究进展综述

下切谷的形成是海(湖)平面相对变化的结果，气候和构造运动的变化可以导致海(湖)平面相对变化。下切谷受形成机制和沉积环境特殊性的影响，具有独特的“U”字型或“V”字型几何特征，独特的形态导致其内沉积物在垂直于下切谷的地震剖面中表现为上超充填型和发散充填型反射结构特征，而在平行或近于平行下切谷走向的地震剖面上，谷内沉积主要表现为斜交型前积反射特征。由于影响下切谷形成与充填的因素众多，导致其一直以来没有一个令人满意的充填模式。下切谷作为一种特殊的层序内部组成要素，其侵蚀–充填演化模式对于层序划分、地层对比、恢复陆架区古环境及确定古海平面位置具有重要的意义。此外，下切谷在油气藏形成过程中既是良好的油气运移通道，又是良好的油气储集场所，对油气勘探均具有重要意义。 The formation of incised valley is the result of relative change of sea (lake) level, which can be affected by the change of climate and tectonic movement. The incised valley is influenced by formation mechanism and sedimentary environment particularity, and it is characterized by symmetric or asymmetric “U” or “V”. Unique shape led that the interior sediment filling has a reflection character of onlap and divergent types in seismic section perpendicular to the incised valley. In parallel or nearly parallel to the incised valley, the interior sediment filling mainly reflects oblique type progradation characteristics. Because of many factors influencing the formation and filling of the incised valley, it has been without a satisfactory filling pattern. Incised valley as a special sequence of internal elements, the erosion-filling evolution model is important for sequence stratigraphy division, stratigraphic correlation, restoration for the ancient environment of continental shelf and determination for the ancient sea level position. In addition, the incised valley is an important migration channel and good reservoir of oil and gas in the process of reservoir formation, and it is of great significance for oil exploration.

Ancient sea monster battle revealed in unusual fossil

Ancient sea monster battle revealed in unusual fossil

Nearshore euxinia in the photic zone of an ancient sea: Part II – The bigger picture and implications for understanding ocean anoxia

Biomarker, palaeontological and isotopic evidence suggests that the Late Permian carbonate seas, i.e. the Northern (NPB) and Southern (SPB) Permian basins of northern Pangea, were characterized by significant spatial and temporal variations in the palaeowater-column redox state. This is particularly the case with regard to the deposition of the Lopingian Zechstein cycle 2 carbonate rocks. A shelf to basin reconstruction of environmental conditions was achieved by analysing nearly 400 core samples from 49 wells. This allowed an evaluation of the spatial variations in facies and broad oceanographic conditions at the basin scale. Specifically, in the lower slope and shallow-basin facies of the northern margin of the SPB (present-day northern Poland and eastern Germany), highly variable concentrations of the green sulphur bacterial biomarkers chlorobactane and isorenieratane (and their likely degradation products, C15 to C31 2,3,6-aryl isoprenoids, indicative of photic zone euxinia) and homohopane indices (indicative of anoxia), combined with the presence of a benthic fauna and bioturbation, indicate a variable but occasionally anoxic/euxinic water column. Locally in lagoonal facies in the northern and southern margin of the SPB, euxinic conditions also developed but these were likely associated with localised conditions or benthic production in association with microbialites. The presence of gammacerane in the eastern SPB (south-eastern Germany and eastern Poland) suggests elevated salinities there, compatible with the restricted configuration of the basin. However, a lack of these signatures in basinal settings of the eastern SPB indicates that strongly reducing conditions were restricted to the lower slope and shallow-basin locations and restricted lagoons, and were not developed in the basin centre. Moreover, this anoxia/euxinia in marginal settings is restricted to the north-eastern part of the SPB. The south-eastern part of the SPB (SE Poland), in contrast, is devoid of evidence for PZE. The southern margin of the SPB is also characterized by generally oxic-suboxic conditions, with local anoxia limited to more restricted embayments, and elevated salinities limited to restricted oxic-anoxic lagoons. In the western SPB (NE England and adjacent offshore) and the NPB (Outer Moray Firth, offshore Scotland) the water columns were oxic-suboxic. Overall, it appears that high but episodic primary bioproductivity of organic matter was concentrated on (or even limited to) the lower slopes of the SPB's north-eastern margin and the restricted lagoons and shallow basin of its southern margin, leading to the formation of source rocks for petroleum in these areas. In addition, the temporal and geographical restriction of anoxia appears to have prevented the accumulation of large and more widespread quantities of organic matter; in fact TOC contents exhibit a poor correlation with ecological and anoxia indicators. Crucially, this work confirms that the strong evidence for PZE observed in shelf and lower slope/shallow-basin facies of the north-eastern SPB need not be associated with widespread, basin-scale anoxia; this conclusion has implications for organic matter burial, carbon cycling and biotic crises during other times in Earth history.

Aquifer Geometry and Water Quality in Relation to Occurrence and Distribution of Peat in Baghia-Chanda Beel, Bangladesh

Baghia-Chanda Beel, largest peat basin in Madaripur and Gopalganj (Bangladesh) districts occupies thick deposits of peat. Study focuses on the aquifer geometry and geochemical evaluation of groundwater in relation to occurrence and distribution of peat. Landuse map is generated to show the surface distribution of peat. Thick peat and clay layer respectively, with an average thickness of 7 ft, has been observed throughout the study area. Principal productive aquifer about 40 ft thick, is found at depth between 35 to 145 ft below ground surface. According to pH and EC values, groundwater is mildly acidic to slightly alkaline and fresh to brackish. High bicarbonate concentration which is more likely to be attributed from the oxidative degradation of peat is found at shallow aquifer below peat. Elevated sodium (Na+) and chloride (Cl-) concentrations in deep aquifer are due to the trapping of ancient sea water in the subsurface during Quaternary period. Although deep aquifer is extensively low in arsenic, 68% and 44% shallow groundwater samples are arsenic (As) contaminated according to WHO, 2011 and Bangladesh Drinking Water Standard (DoE, 1997) limit respectively. Assessment of Water Quality Indexes (WQI>100) suggests that water from deep aquifer is more suitable for drinking purposes.

Plate tectonics reveals evidence of ancient sea beneath the Philippines

Plate tectonics reveals evidence of ancient sea beneath the Philippines