Description: Publication date: 15 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 444 Author(s): Lei Shi, Qinglai Feng, Jun Shen, Tsuyoshi Ito, Zhong-Qiang Chen The Middle Permian is a critical period when a possible cooling regime prevailed and massive deep-water cherty sediments were deposited in the South China Craton. An integration of radiolarian paleoecologic and geochemical studies from the Middle Permian Gufeng cherty succession of western Hubei Province, South China tests the relationships among oceanic productivity, redox conditions, and radiolarian responses as well as origin of the cherts. A total of 21 species and six undetermined species in 10 radiolarian genera are identified from the Gufeng Formation in the northern margin basin of the Yangtze Platform of the South China Craton. Three radiolarian Pseudoalbaillella globosa , Follicucullus monacanthus , and Follicucullus scholasticus zones were established and constrained the Gufeng Formation as Roadian to Middle Capitanian in age. The Gufeng cherts embrace a biologic and hydrothermal origin in the northern marginal basin and southern margin basin (the Nanpanjiang Basin) of the South China Craton, respectively. The high oceanic primary productivity in surface oceans resulted in the widespread reducing conditions in the bottom water column. Such high oceanic productivity event slightly predated the Middle Permian Kamura cooling event of the Panthalassian Ocean. Both the elevated continent weathering due to pre-eruptive crustal uplift of the Emeishan flood volcanism and active oceanic upwelling may have stimulated high oceanic productivity and facilitated the deposition of the Gufeng cherts. All radiolarians bloomed in relatively oxic conditions. Only shallow-water radiolarians, mainly spherical forms, proliferated in the reducing conditions, which also coincided with an enhanced oceanic productivity. The abundance of spherical radiolarians therefore is an ideal proxy indicating oceanic primary productivity.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Fengmei Yang, Naiang Wang, Feng Shi, Fredrik Charpentier Ljungqvist, Sen Zhao, Ting Liu The West Qinling Mountains form part of the climatic barrier that separates southern and northern China, and are located at the edge of the region dominated by the Asian summer monsoon. To investigate the spatial distribution of regional hydroclimatic variability in the West Qinling region, the annually resolved spatial field of rainy season (May–June–July–August–September, MJJAS) precipitation anomalies from AD 1470 to 2000 was reconstructed using 39 tree-ring chronologies, as well as 28 dryness/wetness indices derived from historical documentary data. The results indicate that the El Niño–Southern Oscillation (ENSO) and the Tropospheric Biennial Oscillation (TBO) may jointly affect the spatial pattern of precipitation over the West Qinling Mountains at inter-annual timescales. The drought in the 1990s was found to exceed the amplitude and duration of all other periods of drought that have occurred since AD 1470 in this region. The new precipitation field reconstruction assesses the spatial pattern of historical hydroclimatic variability in the West Qinling region and provides an opportunity to test the performance of climate models in simulating regional precipitation variability and change.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): James R. Thomka, Carlton E. Brett, Thomas E. Bantel, Allison L. Young, Donald L. Bissett Diploporites, like most pelmatozoan echinoderms, are characterized by complex multi-element skeletons prone to complete disarticulation if left exposed for extended periods of time. Consequently, preservation of abundant articulated diploporite thecae is rare and generally restricted to environments where rapid burial events could catastrophically entomb individuals. One such environment is represented by the lower portion of the Wenlock-age Massie Formation at the New Point Stone quarry near Napoleon, southeastern Indiana, which we recognize as a Konservat-Lagerstätte. Yet, taphonomic evidence does not support live burial. Diploporites ( Holocystites spp.) are dominantly preserved as intact thecae without any portions of brachioles and with damage (plate shifting and plate loss/plate jumbling) on one side. Post-mortem encrustation is common, but epibionts are typically present on the well-preserved sides of thecae. Geopetal sediment-fill of thecae shows that the well-preserved side commonly faced upward following burial. This taphonomic state is paradoxical, as burial of live diploporites would have resulted in preservation of complete individuals with no encrusters and only compaction-induced damage; rapid burial of diploporites following a short interval of exposure would have resulted in preservation similar to observed patterns, but with encrusters and geopetal infills indicating that the poorly preserved side faced up; and burial after extended exposure would have resulted in thorough disarticulation of thecae. Rather, a variable and, in some cases, complex taphonomic history is suggested for diploporites from the Napoleon quarry, with at least some individuals having experienced one or more brief episodes of exhumation prior to final burial. Early diagenetic cementation of initial theca-filling sediment is the most likely mechanism for keeping thecae intact during subsequent exposure.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Antony Blundell, Joseph Holden, T. Edward Turner Ombrotrophic peatlands have provided important archives for understanding Holocene palaeoenvironmental change. However, records are predominantly from raised bogs due to potential issues regarding preservation of proxy indicators, record length and low temporal resolution in other peat types including blanket bogs. By carrying out peat depth and stratigraphy surveys we demonstrate how blanket peatlands can provide archives capable of providing records that are not reliant on single proxies, as has been often the case in the past, and can provide good resolution records. A record containing humification, testate amoebae and plant macrofossils was derived for the last 3000 years with accumulation rates as high as 8 yrs cm − 1 providing favourable temporal resolution, particularly over the last 1500 years. Major changes in proxy indicators reflecting potential changes in water-table depth were often coherent with changes in climate. Human activity also had a major impact on the peatland throughout the record especially in the last 100 years where the influence of wildfire and managed burning, together with an effect of atmospheric pollution, fundamentally changed the state of the peatland.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Renata Zocatelli, Patricia Moreira-Turcq, Jérémy Jacob, Renato Campello Cordeiro, Mohammed Boussafir, Claude Le Milbeau, Marcelo Bernardes, Bruno Turcq This study on Curuai Floodplain (Central Amazonia) sediments (last 5600 cal yr BP) focused in Rock‐Eval [RE; hydrogen (HI) and oxygen (OI) indices, Tmax, S2 curve and TpS2], organic petrography and molecular biomarkers [ n -alkanes, hopanes, pentacyclic triterpene methyl ethers (PTMEs) and derivatives of pentacyclic triterpenes such as des-A-lupane and aromatic derivatives] analyses. Between 5600 and 5100 cal yr BP, the environment was waterlogged and dominated by emersed plants (Paq 0.27–0.38). The influence of the Amazon River was low. Terrestrial vs aquatic ratio (T/A, ~ 0.8), CPI values (3–4) and high contents of PTME (0.22–1.54 μg/g sed) and aromatics (21–53 μg/g sed) indicated a strong contribution of terrestrial material and anoxic OM deposition conditions. Between 5100 and 5000 cal yr BP more humid conditions due to heavier rainfalls were observed. Early in this period, terrestrial biomarker contents (253 μg/g sed of aromatics, Paq ~ 0.17) increased due to input of watershed erosion material. This provoked a rapid burial and good preservation of terrestrial OM (CPI 3–4.5). From 5000 cal yr BP a strong sedimentation of carbonate minerals (OI ~ 1600 mg CO 2 ·g − 1 ) masked the OM signal and affecting RE parameters. Paq (~ 0.18), T/A ratio (~ 0.4) and the decrease of C 31αβ /C 31ββ hopanes (1.18) indicate increasing aquatic conditions up to 2700 cal yr BP. CPI ratio (~ 1.2) and degraded phytoclasts suggest intense degradation during transport to the sedimentation location. The PTMEs results showed that, from 3000 yr cal BP, the Poaceae genera were different from those found at the bottom (middle-Holocene), suggesting a change of vegetation. The last 600 cal yr BP were marked by the seasonal influence of the Amazon River; during periods of low water level, the organic petrography and CPI values (~ 1.0) evidenced OM degradation and the return of rather drier conditions.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Barbara V. Radulović, Vladan J. Radulović, Dmitry A. Ruban Rich brachiopod assemblages are known from the Lower and Middle Jurassic deposits of the Danubian and Getic tectonic units (eastern Serbia). A quantitative assessment of the relevant palaeontological data can shed light on the relationship of these units in the palaeospace. In the present study, the brachiopod assemblages from the Danubian and Getic tectonic units are compared with similarity indices (the Jaccard similarity of species, genera, families, and superfamilies, and the Czekanowski and Gower similarity of the genus–species, family–species, and superfamily-species diversity structures). This analysis is applied to five geological time slices when brachiopods flourished regionally, namely the Early Pliensbachian, the Late Bajocian, the Early Bathonian, the Middle Bathonian, and the Late Bathonian. Generally, the values of the indices imply moderate similarity. The similarity was significantly lower in the Middle Jurassic relatively to the Early Jurassic. The similarity of the Early Pliensbachian brachiopods of the Danubian and Getic tectonic units was significant relatively to the similarity between some European regions. The documented decrease in the similarity through the geological time can be explained by the increase in the global palaeobiogeographical differentiation in the Middle Jurassic. Graphical abstract

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Montserrat Sanz, Joan Daura, Natalia Égüez, Jean-Philip Brugal Three morphotypes of fossil fecal material (coprolites) have been identified from the Upper Pleistocene site of Cova del Coll Verdaguer (NE Iberian Peninsula). Coprolites are commonly found in Pleistocene records and also in places in which human and carnivore activities co-occurred. However, coprolite identification is typically limited to hyenids, the most readily recognizable fossilized feces, owing to their distinctive shape and good preservation, although non-hyena carnivore coprolites are also likely to be present in these assemblages. Several criteria for a multi-scale integrative analysis are proposed here for discriminating different morphotypes. Hence, this analysis provides an opportunity to assess the involvement of several carnivores in bone accumulations, to identify carnivores not specifically represented by skeletal remains and to evaluate interactions between humans and the carnivore guild, especially medium and small carnivores.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): María Cristina Cardonatto, Renata Sostillo, Graciela Visconti, Ricardo N. Melchor Invertebrate trace fossils from the late Miocene Cerro Azul Formation (La Pampa, Argentina) are described and compared with known paleosol ichnofacies. The formation is a loess succession punctuated by numerous calcareous paleosols. Trace fossils were recovered from thirteen localities distributed in a wide latitudinal and longitudinal range within La Pampa Province. Paleosols from the northwestern localities display clastic dikes and pedogenic slickensides and are compared with calcic vertisols, which are typical of strongly seasonal and semiarid climate. Paleosols from the remaining localities have a Bt horizon with blocky or prismatic peds and can be compared with mollisols. The depth to the Bk horizon for all paleosols averages 0.54 m, suggesting a mean annual precipitation of 450 mm (± 147 mm), also pointing to semiarid climatic conditions during soil formation. The trace fossil assemblage from the Cerro Azul Formation is of low diversity and abundance and is typified by the presence of the insect trace fossils Celliforma , Rosellichnus , Rebuffoichnus , Fictovichnus and Teisseirei . The ichnospecies recorded are: Celliforma germanica , Celliforma cf. rosellii , Celliforma isp., Rosellichnus isp., Rebuffoichnus casamiquelai , Fictovichnus cf. sciuttoi , Fictovichnus isp., Teisseirei barattinia , Taenidium barretti , and cylindrical burrow fills. These trace fossils (along with Attaichnus kuenzelii , vertebrate burrows and medium–sized rhizoliths described in previous works) are considered comparable with the Celliforma ichnofacies. This ichnofacies is indicative of well-drained calcareous paleosols developed under low vegetation coverage. For the analyzed succession the vegetation was probably dominated by scrubs with minor participation of herbaceous plants. Coprinisphaera ispp. (including Coprinisphaera lazai , Coprinisphaera murguiai , and Coprinisphaera isp.) showing a cementation similar to associated late Miocene trace fossils were only recorded, along with Celliforma isp., in two localities. This trace fossil assemblage is comparable with the Coprinisphaera ichnofacies, suggesting dominance of herbaceous communities and wetter climate than those of the Celliforma ichnofacies. Some specimens of uncemented Coprinisphaera ispp. were produced during post-Miocene times and are not considered as a part of the trace fossil assemblage of the Cerro Azul Formation.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Susan R. Beardmore, Heinz Furrer Studies of preservation have allowed environmental conditions at numerous localities in space and time to be inferred. However, in the search for sufficient vertebrate specimens to provide a large dataset, details of specimen taxonomy, geographic origin and stratigraphic level are often ignored or not collected. Any preservational variation identified as a result is therefore from a broad range rather than a specific group, locality or time. The effect of this limitation, mainly regarding the loss of crucial information on environmental processes in ancient settings and the biology of long extinct organisms, is demonstrated using specimens of Ichthyopterygia (Reptilia). Taphonomic analysis of a dataset of 173 specimens infers a consistent reduction of skeletal condition from peripheral to medial within a carcass and a taphonomic pathway involving minimal floating and prolonged residence on the sediment surface. The same dataset divided into three sub-datasets, from the Middle Triassic Besano Formation, Lower Jurassic Blue Lias Formation and Lower Jurassic Posidonia Shale Formation, highlight preservational variation, in the extent of loss of articulation and completeness that follows an environmental gradient related to proximity to major landmasses.

Description: Publication date: 1 February 2016 Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 443 Author(s): Lina Wang, Paul B. Wignall, Yongbiao Wang, Haishui Jiang, Yadong Sun, Guoshan Li, Jinling Yuan, Xulong Lai In many tropical shallow water regions the end-Permian mass extinction event occurs at the top fossiliferous packstone beds and is immediately followed by the development of microbialite facies. Both the age and redox conditions of the microbialite have been debated and both factors are addressed here in a study of the Gaohua section (Cili County, Hunan Province, China): specifically the size distribution of pyrite framboids and high-resolution conodont biostratigraphy. The framboids populations show a broad size range with examples up to 30 microns in diameter, and indicating dysoxic but not anoxic depositional conditions. More intense dysoxia is recorded in interbedded laminated micrites but not beds of giant ooids. Both the Hindeodus parvus zone and Isarcicella isarcica zones were established with the microbialite beds being confined to the H. parvus zone. Therefore, the formation of microbialite postdates the end Permian main mass extinction and records oxygen-poor conditions even in a shallow-water setting such as Gaohua section at Cili.