Long-term trends in planetary wave activity (2–15 days) at 80–100 km inferred from radio wave absorption

The daytime radio wave absorption in the lower ionosphere measured by the A3 method (oblique incidence on the ionosphere) in central and southeastern Europe is used to study long-term trends in the planetary wave activity in the period range of 2–15 days in the upper middle atmosphere. In central Europe we have found no trends in the 1960s and 1980s, but a positive trend in the 1970s (early 1970s- early 1980s); in southeastern Europe we have not established any trend in the 1970s, but a positive one in the 1980s (beginning in late 1970s). These trends are of non-solar origin. They are possibly an indication of changes of anthropogenic origin in the Earth's atmosphere.     

An assessment of winds data (60–110 km) obtained in real-time from a medium frequency radar using the radio wave drifts technique

In a recent paper (Meek, 1980) a fast and efficient method for analysing ionospheric drift records was described. The technique is well suited to real-time analysis.Examples of winds data (60–110 km) obtained from the medium frequency (2.2 MHz) radar at Saskatoon (52°N, 107°W) during 1980 are described here. The quantity and quality of data obtained during typical summer and winter months are discussed. Height time cross-sections of mean winds and tides are also shown.     

Mean winds at 60–90 km observed with the MU radar (35°N)

Mean winds at 60–90 km altitudes observed with the MU radar (35°N, 136°E) in 1985–1989 are presented in this paper. The zonal wind at 70 km became westward and eastward in summer and winter, respectively, with a maximum amplitude of 45 m s⁻¹ westward in early July and 80 m s⁻¹ eastward at the end of November. The meridional wind below 85 km was generally northward with the amplitudes less than 10 m s⁻¹. In September to November, the meridional wind at 75–80 km becomes as large as 20–30 m s⁻¹. Those zonal wind profiles below 90 km show good coincidence with the CIRA 1986 model, except for the latter half of winter, from January to March, when the observational result showed a much weaker eastward wind than the CIRA model. The height of the reversal of the summer wind from westward to eastward was determined as being 83–84 km, which is close to the CIRA 1986 model of 85 km. The difference between the previous meteor radar results at 35–40°N, which showed the reversal height below 80 km, could be due to interannual variations or the difference in wind measurement technique. In order to clarify that point, careful comparative observations would be necessary. These mean winds were compared with Adelaide MF radar observations, and showed good symmetry between the hemispheres, including the summer reversal height, except for the short period of eastward winds above Kyoto and the long period over Adelaide.     

Climatologies of semi-diurnal and diurnal tides in the middle atmosphere (70–110 km) at middle latitudes (40–55°)

The radars utilized are meteor (2), medium-frequency (2) and the new low-frequency (1) systems: analysis techniques have been exhaustively studied internally and comparatively and are not thought to affect the results. Emphasis is placed upon the new height-time contours of 24, 12 h tidal amplitudes and phases which best display height and seasonal structures; where possible high resolution (10 d) is used (Saskatoon) but all stations provide monthly mean resolution. At these latitudes the semi-diurnal tide is generally larger than the diurnal (10–30 m s⁻¹ vs. < 10 ms⁻¹), and displays less month to month variability. The semi-diurnal tide does show significant regular seasonal structure; wavelengths are generally small (⩽50 km) in winter, large in summer (≲ 100 km), and these states are separated by rapid equinoctial transitions. There is some evidence for less regularity toward 40°C. Coupling with mean winds is apparent. The diurnal tide has weaker seasonal variations; however there is a tendency for vertical wavelengths and amplitudes to be larger during summer months. On occasions in winter and fall wavelengths may be less than 50 km. Again the seasonal transitions are in phase with reversals of the zonal wind. Agreement with new numerical models is to be shown encouraging.     

Wind corners in the 70–100 km altitude range as observed at andenes (69° latitude)

In the altitude range 70–100 km, high-resolution wind profiles have been measured during the summers of 1987 and 1988 at Andenes (69°N). We report on the wind corners observed in these profiles and compare their properties with those of wind corners seen in the winter of 1983–1984 and autumn 1987. Five of the main results are as follows. (1) The occurrence rates for wind corners in general are similar in summer and in winter. The database for autumn (only 7 flights) was too small to draw any firm conclusions. A strong wind corner was seen, roughly, on every third experiment, both in summer and in winter. (2) The results obtained on the temporal occurrence of wind corners suggest that wind corners seem to have no preference to appear at certain hours of the day. (3) Wind corners tend to appear at preferred heights which are higher in summer than in winter. The spacing between these preferred heights is about 5 km in summer and about 3-3.5 km in winter. (4) In strong wind corners the sense of rotation of the wind direction is positive in summer and negative in winter (with positive being defined as a rotation of the wind direction from northward towards eastward with increasing altitude). (5) At altitudes below 90km wind corners tend to occur at or close to atmospheric layers having Ri ≈ 0.25.     

Anomalous diurnal phase shifts of Omega VLF waves (10–14 kHz) on the east–west low latitude and transequatorial paths

The phase of the Omega HAIKU (Hawaii, U.S.A.) and REUNION (La Reunion) signals were measured at Inubo, Japan and onboard ship at Fremantle. Australia. Strong east–west non-reciprocities of the diurnal phase shift are obtained both on the low latitude and transequatorial paths, and it is found that the non-reciprocity on one path is in an opposite sense to the other. The diurnal phase shift, ϕ_DN for the west-to-east (WE) propagation is 7.8–8.7 µs Mm^–1 at 13.6 kHz on the transequatorial and mid-latitude paths, indicating no significant latitude dependence of the phase velocity in WE propagation. On the other hand, ϕ_DN for the east-to-west (EW) propagation greatly depends on the geomagnetic latitude; at 13.6 kHz ϕ_DN = 11.3µs Mm^–1 on the low latitude path and ϕ_DN = 50 µs Mm^–1 on the transequatorial path, which are 40% greater and 35% less than ϕ_DN in WE propagation, respectively. The east-west non-reciprocities of ϕ_DN on the low latitude and transequatorial paths are interpreted in terms of a single mode propagation in the conventional anisotropic waveguide model with β_D = 0.3 km^–1, β_N = 0.5 km^–1 and h_N–h_D = 12.5 km. In particular, the anomalously small ϕ_DN on the EW transequatorial path is explained as due to the high phase velocity of the night-time first-order mode in the equatorial region within ±12° geomagnetic latitude.     

Elasmosaurs (Sauropterygia,Plesiosauria) from the La Colonia Formation (Campanian–Maastrichtian), Argentina

O’Gorman, J.P., Salgado, L., Varela, J., & Parras, A., 2013. Elasmosaurs (Sauropterygia, Plesiosauria) from the La Colonia Formation (Campanian–Maastrichtian), Argentina. Alcheringa 37, 257–265. ISSN 0311-5518.

Elasmosaur postcranial remains from the La Colonia Formation (Campanian–Maastrichtian), Chubut Province, Patagonia, Argentina, are described. The new material has small dimensions and caudal vertebrae with parapophyses strongly projected laterally—characters shared with some Elasmosauridae indet. from the coeval Allen Formation, Río Negro Province, Argentina. These features reinforce the similarities between the plesiosaur faunas to the north and south of the Somún Curá Plateau. The small size of these elasmosaurs may be palaeoecologically related to the marginal marine depositional environment of the sedimentary host rocks.

José P. O’Gorman [joseogorman@fcnym.unlp.edu.ar], División Paleontología Vertebrados, Museo de La Plata, Universidad Nacional de La Plata, Paseo del Bosque s/n., B1900FWA, La Plata, Argentina and [CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas)]; Leonardo Salgado [salgadoleito@yahoo.com.ar], Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, Isidro Lobo y Belgrano, 8332 General Roca, Argentina and [CONICET]; Julio Varela [julioadrianvarela@hotmail.com], and Ana Parras [aparras@exactas.unlpam.edu.ar], INCITAP (CONICET-UNLPam), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. Received 27.7.2012; revised 19.10.2012; accepted 27.10.2012.     

Dynamics of the upper middle atmosphere (80–110 km) at Tromsø (70°N) and Saskatoon (52°N), June–December 1987, using the Tromsø and Saskatoon MF radars

A real-time-winds (RTW) system from Saskatoon operated with the Tromsø MF (partial reflection) radar system on a continuous basis in the period June–December 1987. This interval includes MAC/SINE and EPSILON. Profiles with 3-km resolution were obtained every 5 min—weak ionization and few geomagnetic disturbances limited the observations normally to 80–110 km. However, daily mean winds, diurnal and semidiurnal tidal characteristics (amplitudes, phases and wavelengths) and gravity wave characteristics (intensities, mean directions) are available throughout this interval. This is particularly valuable in defining the background state for some experiments, e.g. rockets, and for comparison with related parameters from the lidar and other radars (EISCAT, SOUSY-VHF). Comparisons with these dynamical parameters from Saskatoon (52 N) are made : the zonal circulation was weaker at Troms0, tidal amplitudes smaller, and summer 12-h tidal wavelengths shorter ( ~ 80 km vs ~ 100 km). The fall transition for this tide occurred in September at Troms0, earlier than observed elsewhere.     

Multi-resolution morpho-bathymetric survey results at the Pozzuoli–Baia underwater archaeological site (Naples,Italy)

Here we show the results of two morpho-bathymetric surveys carried out on the underwater archaeological area of the Pozzuoli Bay (Naples, Italy). Such area is enclosed in the Campi Flegrei active volcanic complex, where bradyseism and recent volcanic activity strongly influenced the coastline shape over the last 2 Ka. The Digital Elevation Model (DTM) of the seafloor allowed to draw the main archaeological features of the Bay, that also include the military complex of Portus Iulius and the ancient thermal and villa complex of Baianus Lacus. The extraction of archaeological features from DTM was achieved thanks to the use of a GIS-derived tool based on the profile curvature algorithm. Thus, the Villa dei Pisoni (1st Century B.C.) and the thermal complex of Secca delle Fumose were investigated by using ultra-high resolution DTMs, that show the presence of Roman pilae for the protection of coastal buildings and also the inner planimetry of the Villa dei Pisoni complex. The observation of coastal engineering structures give also the opportunity to formulate some hypothesis on the evolution of morphology and of the sedimentary pattern of the area, while depth of archaeological remains allowed a rough computation of the rate of subsidence, resulted to be 2.55 (±0.5) mm/y for the Eastern sector (Pozzuoli) and 2.90 (±0.5) mm/y for the western (Baia).     

Lithic Production and Consumption Patterns from the Great Platform at Late Postclassic (A.D. 1350–1525) Tzintzuntzan,Mexico

Late Postclassic period (a.d. 1350–1525) Tarascan economic activities often included higher degrees of political involvement and territorial control compared with other ancient Mesoamerican societies. Here I examine Tarascan obsidian economies through an analysis of lithic production and consumption patterns from structures excavated on and near the Great Platform at the imperial capital of Tzintzuntzan. Four spatially distinct patterns are evident. Great Platform residents used high-quality obsidian blades as ceremonial items or burial offerings and scrapers for craft production. Lower elite residents of Structure F, outside the Great Platform, produced their own blade tools and consumed a higher percentage of green obsidian than residents of the Great Platform. Excavations at Yacata 3 recovered bifacial arrowheads and obsidian bloodletters associated with disturbed offerings. The spatial distributions of lapidary preforms and highly polished fragments combined with accounts from the Relación de Michoacán (a.d. 1541) suggest that lower elites produced obsidian jewelry near the Great Platform.     

Early Aptian (Early Cretaceous) freshwater bivalves from the Australian–Antarctic rift,southeast Victoria

The brissid echinoid Schizobrissus insignis (Duncan &; Sladen, 1883) is described from the Fulra Limestone (late middle Eocene), in Kachchh, India. Formerly assigned to Peripneustes or to Meoma it is shown that the species possesses a complete subanal fasciole throughout ontogeny, a characteristic feature of Schizobrissus. Eocene species of Schizobrissus and Meoma show several morphological similarities, but diverged during the late Paleogene and early Neogene.     

Archaeometric analysis of the ‘greco scritto’ marble slabs from the Edificio dei Triclinii at Murecine (Pompeii,Italy)

This paper presents the results of the archaeometric analysis of the greco scritto marble slabs from the Edificio dei Triclinii, an inn or statio negotiatorum discovered at Murecine in Pompeii’s suburbs in 1999–2000. A total of 14 samples were collected and subjected to standard X-ray diffraction (XRD), optical microscopy (OM) on thin sections and stable isotope ratio analysis (SIRA) to assess the stone’s identity and provenance. The results of this study substantiate the hypothesis (already put forward and based on a macroscopic identification by Perna and Scognamiglio) that the stone originates from the Hasançavuşlar quarries near Ephesus in Asia Minor, and represent the first step towards a systematic contextual and geochemical study of Ephesian greco scritto in Roman contexts and its respective contribution to the Roman stone trade.     

Palaeoecological insights into the Changhsingian–Induan (latest Permian–earliest Triassic) bivalve fauna at Dongpan,southern Guangxi,South China

Yang, T.L., He, W.H., Zhang, K.X., Wu, S.B., Zhang, Y., Yue, M.L., Wu, H.T. & Xiao, Y.F., November 2015. Palaeoecological insights into the Changhsingian–Induan (latest Permian–earliest Triassic) bivalve fauna at Dongpan, southern Guangxi, South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

The Talung Formation (latest Permian) and basal part of Luolou Formation (earliest Triassic) of the Dongpan section have yielded 30 bivalve species in 17 genera. Eight genera incorporating 11 species are systematically described herein, including three new species: Nuculopsis guangxiensis, Parallelodon changhsingensis and Palaeolima fangi. Two assemblages are recognized, i.e., the Hunanopecten exilis–Euchondria fusuiensis assemblage from the Talung Formation and the Claraia dieneri–Claraia griesbachi assemblage from the Luolou Formation. The former is characterized by abundant Euchondria fusuiensis, an endemic species, associated with other common genera, such as Hunanopecten, which make it unique from coeval assemblages of South China. A palaeoecological analysis indicates that the Changhsingian bivalve assemblage at Dongpan is diverse and represented by various life habits characteristic of a complex ecosystem. This also suggests that redox conditions were oxic to suboxic in deep marine environments of the southernmost Yangtze Basin during the late Changhsingian, although several episodes of anoxic perturbations and declines in palaeoproductivity saw deterioratation of local habitats and altered the taxonomic composition or population size of the bivalve fauna.

Tinglu Yang [yang@geology.so], School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China; Weihong He* [whzhang@cug.edu.cn] and Kexin Zhang [kx_zhang@cug.edu.cn], State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China; Shunbao Wu [shbwu@cug.edu.cn], Yang Zhang [zhangy05@163.com], Mingliang Yue [812182779@qq.com], Huiting Wu [ht_wu415@163.com] and Yifan Xiao [shadowyi@sohu.com], School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China.     

Pliocene Mollusca (Bivalvia,Gastropoda) from the Sørsdal Formation,Marine Plain,Vestfold Hills,East Antarctica: taxonomy and implications for Antarctic Pliocene palaeoenvironments

Quilty, P.G., Darragh, T.A., Gallagher, S.J. & Harding, L.A. July 2016. Pliocene Mollusca (Bivalvia, Gastropoda) from the Sørsdal Formation, Marine Plain, Vestfold Hills, East Antarctica: taxonomy and implications for Antarctic Pliocene palaeoenvironments. Alcheringa 40, XXX–XXX. ISSN 0311-5518.

Pliocene shallow-water marine sediments at Marine Plain (centred on 68°37.7?S; 78°07.8?E) and covering approximately 10 km² in the Vestfold Hills, East Antarctica, have yielded six species of gastropods, and 11 species of bivalves from two beds within the Sørsdal Formation. Most of the material is close to in situ but some specimens have been disturbed from their life position; there is no evidence of significant transport. The gastropods include Nacella concinna (Strebel, 1908), Falsimargarita parvispira Quilty, Darragh, Gallagher & Harding sp. nov., indeterminate species of trochids and naticids, Chlanidota (Chlanidota) sp. cf. C. signeyana Powell, 1951, and two species of Trophon/Trophonella. Bivalves include Ennucula sp. aff. E. grayi (d’Orbigny, 1846), Aequiyoldia defossata Quilty, Darragh, Gallagher & Harding, sp. nov., ‘Pectunculina’ sp., Lissarca sp., Austrochlamys anderssoni (Hennig, 1911), Ruthipecten campestris Quilty, Darragh, Gallagher & Harding sp. nov., Adamussium necopinatum Quilty, Darragh, Gallagher & Harding sp. nov., Limatula (Antarctolima) sp. cf. L. hodgsoni (Smith, 1907), Cyclocardia magna Quilty, Darragh, Gallagher & Harding sp. nov., ?Hiatella sp. cf. H. arctica (Linnaeus, 1767) and Laternula elliptica (King, 1832). Preservation varies considerably owing to recrystallization, dissolution or distortion through compaction, so several species are left in open nomenclature. Oxygen isotope data indicate that water temperature was 4–7.5°C at the time of shell growth. Many species or species groups are now extinct or have migrated away from the Antarctic to the sub-Antarctic region. An Antarctic mollusc fauna has been characteristic of the region for much of the Cenozoic.

Patrick G. Quilty [p.quilty@utas.edu.au], Discipline of Earth Sciences, University of Tasmania, Private Bag 79, Hobart, Tasmania 7001, Australia; Thomas A. Darragh [tdarragh@museum.vic.gov.au], Museum Victoria, GPO Box 666 Melbourne, Victoria 3000, Australia; Stephen J. Gallagher [sjgall@unimelb.edu.au], School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia; Lucy A. Harding [harding.lucy.a@edumail.vic.gov.au], School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia.     

Skates and Prickers from the Circular Fortress of Oost-Souburg,The Netherlands (AD 900–975)

Abstract

During the excavation of the circular fortress of Oost-Souburg, the Netherlands, objects of bone and antler were found: combs, needles, spindles, three-pronged objects, bone skates and points. The finds are dated between AD 900 and 975. In this contribution the objects which belong to the winter season, the bone skates and the points, are discussed. The skates occur in various types and are made of a variety of bones. Certain types of skate were used without bindings, others were either designed to be fastened to the feet or possibly were tied only at the heels. The roughly-made points that were found may be the points of the prickers used to propel the skater forward on his skates.     

Copper production at Baratti (Populonia,southern Tuscany) in the early Etruscan period (9th–8th centuries BC)

Populonia is commonly regarded as one of the most important iron working centres in Europe in the 1st millennium BC. However, multiple layers of copper slags have been recently discovered at the bottom of the slag deposit occurring along the shoreline of the underlying Baratti Gulf. Copper slag layers have been radiocarbon dated to the 9th–8th centuries BC, i.e. to an early metallurgical stage predating the later large-scale iron production. The overall features of copper slags indicate a single-step smelting process of copper-rich ores containing variable amounts of Zn and Pb. Chemical and textural features of copper slags indicate an optimised, high-efficiency metallurgical process.     

Kukulkanus,a new genus of buxtoniin brachiopod from the Artinskian–Kungurian (Early Permian) of Mexico

Torres-Martínez, M.A., Sour-Tovar, F. & Barragán, R., November 2017. Kukulkanus, a new genus of buxtoniin brachiopod from the Artinskian–Kungurian (Early Permian) of Mexico. Alcheringa 42, 268–276. ISSN 0311–5518.

Kukulkanus is the first genus of the tribe Buxtoniini recorded from rocks of the late Cisuralian (Artinskian–Kungurian). The Early Permian (Cisuralian) outcrops of the Santa Rosa Group, from southeastern Chiapas, are one of the most important marine Palaeozoic successions of Mexico. The Artinskian–Kungurian Paso Hondo Formation is the youngest unit in the succession and is dominated by massive limestone. Different marine invertebrates deposited in massive calcareous rocks characterize this formation. The buxtoniin Kukulkanus spinosus gen. et sp. nov. is reported from a single bed within the unit. The outcrops are located in southeastern Chiapas, very near the Guatemala–Mexico border. The lithological features and the preservation of fossils indicate that the fossil-bearing rocks were deposited in a low-energy open-waters paleoenvironment over the continental platform. Fusulinids, cephalopods and brachiopods previously described for the Paso Hondo Formation have been correlated with faunas of different coeval localities from Texas, New Mexico, Coahuila, Chiapas and Venezuela, regions that form part of the biotic Grandian Palaeo-Province.

Miguel A. Torres-Martínez [miguelatm@geologia.unam.mx] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Francisco Sour-Tovar [fcosour@ciencias.unam.mx] Museo de Paleontología, Facultad de Ciencias, Universidad Nacional Autónoma de México. Av. Universidad No. 3000, Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Ricardo Barragán [ricardor@geologia.unam.mx] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico.