A new fossil species of small crested caracara (Aves: Falconidae:Caracara) from the Pacific lowlands of western South America

A ~10-km-thick sequence of basaltic to rhyolitic volcanic rocks forms the arc component of the Cretaceous Lancones basin in northwestern Peru and underlies part of the Huancabamba deflection. The marine volcanic successions show markedly different compositional features and depositional facies consistent with a maturing arc within a shallowing marine basin. The earliest volcanism accompanying rifting was dominated by basaltic pillow lava and breccia with lesser aphyric to feldspar-quartz porphyritic felsic volcanic rocks. These volcanic successions filled the lowest exposed portion of the basin and were accompanied by volcanogenic massive sulfide (VMS) deposits, which are inferred to have formed in a localized but relatively deep marine setting. U-Pb zircon dating of felsic volcanic rocks associated with VMS deposits at Tambogrande indicates ages from 104.8 ± 1.3 to 100.2 ± 0.5 Ma for the ore-bearing volcanic sequence. The timing of onset of rift-related volcanism is not well constrained but is therefore of middle Albian age or older. Subsequent latest Albian to Turonian volcanism is composed of successions of relatively more felsic rich volcaniclastic rocks and yields U-Pb zircon ages of 99.3 ± 0.3 to 91.1 ± 1.0 Ma. These later volcanic successions are intercalated and overlain by siliciclastic and carbonate sedimentary sequences prevalent in the western forearc section of the Lancones basin. Finally, the basin was intruded by Late Cretaceous to Tertiary granitoids of the Coastal batholith. The genesis of the Cretaceous Lancones basin and other equivalent volcanic rift-related, marginal basins in western South America, including the western Peruvian trough, is related tectonically to the break-up of Gondwana. Early volcanism and associated VMS deposits formed in the Lancones basin during the Albian coincided with the initial rifting stage, prior to active oceanic spreading, between South America and Africa. During this time the relatively stationary western margin of continental South America was undergoing extension and rifting due to a westward and oceanward retreating arc, resembling a Mariana arc-type setting. The Mochica orogeny marks the termination of rifting, subsidence, and related volcanism along the western margin of South America. This orogenic event also broadly coincides with the onset of spreading of the South Atlantic and westward drift of the South American continent. Subsequent volcanism in the Lancones basin was more continental arclike under an Andean-type scenario.

A survey of the hydrochemistry and isotopes of the Quaternary aquifer on the southern coast of Laizhou Bay provides new insights into the hydrodynamic and geochemical relationships between freshwater, seawater, and brine at different depths in coastal sediments. This study used a combination of groundwater level analysis, hydrochemistry, and isotopic methods to study the chemical characteristics of groundwater and the origin of groundwater recharge and salinity. Because the sedimentary structure of the area and the formation background of saltwater were important factors controlling the distribution of groundwater, we analyzed the distribution of groundwater in Holocene and Late Pleistocene sediments. The variation of groundwater levels in the Holocene and Late Pleistocene sediments in the saline–freshwater transition zone over time showed that the Holocene and Late Pleistocene groundwater flow directions differed in the saltwater–freshwater transition zone. From south to north in the study area, the hydrochemical types of groundwater in the Holocene and Late Pleistocene sediments were as follows: HCO3-Ca (freshwater), SO4-Mg and HCO3-Ca (brackish water), Cl-Na·Mg (saltwater), and Cl-Na (brine). The results of the hydrochemical and isotopic studies indicated that the saltwater in the Holocene and Late Pleistocene sediments and the brine in the Late Pleistocene sediments were the result of evaporation. The salinity of freshwater in the Holocene sediments was produced by rock weathering, while the salinity of freshwater in the Late Pleistocene sediments was not only derived from rock weathering, but was also affected by evaporation and precipitation. The salinity of brackish water in the Holocene and Late Pleistocene sediments was derived from evaporation and precipitation. Ultimately, the origin of groundwater recharge in the Holocene and Late Pleistocene sediments was atmospheric precipitation.

Early in 1960, D.A. Hooijer received three large Manis sp. bones recovered from archaeological excavations underway in the West Mouth of Niah Cave, Sarawak, Borneo. Hooijer compared the fossils from Niah with equivalent specimens from both the giant extinct Manis palaeojavanica of Java and the modern M. javanica. He concluded that there was little difference in the morphology of the bones from the Borneo and Java specimens, and thus attributed the skeletal elements from Niah to the extinct form described by Eugene Dubois, M. palaeojavanica. During new investigations of the animal bones recovered during the 1950’s and 1960’s excavations at Niah Cave the authors identified a further five skeletal elements of this rare fossil vertebrate in assemblages from late Pleistocene deposits. Comparisons of the new skeletal elements from Niah with fossil Manis and Macrotherium remains from Java and India suggest that the palaeogeography of the large pangolins of Asia is more complex than Hooijer envisaged. This paper describes the new Manis sp. bones from Niah cave and discusses the palaeobiological and taxonomic relationship between Manis palaeojavanica from Java, the Manis specimens discovered in Borneo and the Late Pliocene Indian Pholidota in light of these new discoveries.

In spite of comprising more than 50% of the world's 10,000+ living species of birds, the songbirds (Passeriformes) generally have a poor fossil record. An exception is the Icteridae, with substantial Quaternary fossils at certain sites in North America, South America, and the West Indies. Here we describe 2 new extinct species of icterids from the late Pleistocene Talara Tar Seeps of northwestern Peru. The first is Icterus turmalis, based on 22 fossils (2 skeletal elements); I. turmalis was part of the radiation of “troupial”-type orioles (Icterus icterus s.l.). The second new species, Molothrus resinosus, was a large cowbird based on 15 fossils (4 skeletal elements). Icterus turmalis and Molothrus resinosus are both known thus far only from Talara. They become the second and third extinct species of icterid known from Talara, the other being Euphagus magnirostrisMiller 1929, first described from Rancho La Brea, and recorded recently from Talara as well as the Mene de Inciarte Tar Seep in Venezuela. Just as some extant species of icterids often occur today alongside large grazing mammals, the extinct species may have been closely associated with the Pleistocene large mammal community, which collapsed from 15 to 12 thousand years ago.

Aminostratigraphy of Middle and Late Pleistocene deposits in The Netherlands and the southern part of the North Sea Basin

A LARGE and distinctive species of the dung beetle Aphodius that is clearly not a member of the present day European fauna has frequently been found in deposits in England that date from the middle of the Last Glaciation1,2. Although at times very abundant (from one peaty lens in a gravel pit near Dorchester on Thames, fossils of at least 150 individuals were obtained) the identity of this species has up to now remained a mystery. The fact that the skeletal elements were to a large extent disarticulated made the use of keys to identification impossible and, with more than five hundred described species of Aphodius in the Palaearctic region alone, it would have been imprudent to describe the fossils as a new, possibly extinct, species. Thus in accounts of fossil assemblages of Coleoptera, this species has been given the non-committal designation of Aphodius sp. A of Upton Warren after the site in Worcestershire1 where it was first found. The solution to the identity of this species was both unexpected and dramatic.

In Ecuador and northwestern Peru the Andes and adjacent country, particularly on the Pacific side, are composed of at least five distinctive geologic terranes. The terranes are distinguished from one another and from cratonic South America to the east by dissimilar basements, cover rocks, intrusive rocks, and Bouguer gravity anomaly fields.The Piñón terrane, occupying most of coastal Ecuador, has a basaltic basement characterized by the largest known on-land positive Bouguer anomalies in the western hemisphere. The Tahuín terrane occupies most of northwestern Peru and the southwestern corner of Ecuador. The terrane has an especially complex basement and is the site of generally positive Bouguer anomalies. The small Birón terrane has an unusual basement composed in part of cordierite gneiss and amphibolite that give consistent Late Cretaceous K – Ar mineral ages. The wedge-shaped Chaucha terrane lies in part on the western Andean slope, between the oceanic Piñón terrane on the north and the continental Birón terrane on the south. The vast Santiago terrane composes the high Andes of southern Ecuador and northwestern Peru. It is the site of the unique Santiago Formation, a thick succession of Lower Jurassic limestones found nowhere else in the region.Geologic and geophysical evidence supports the view that the five terranes are parautochthonous or allochthonous fragments emplaced against cratonic South America from Middle Jurassic to Late Eocene time. Continental-border subduction alone (at the so-called "Andean margin") may have been an inadequate engine for orogeny. Additional allochthonous terranes perhaps await identification at other places along the Andes. Whether the emplacement of allochthonous terranes has been an important process elsewhere in the tectonic development of the Andes remains to be established. Geologic mapping on the oceanward western border of the Andean orogen, studies of basement petrology and chronology, and paleomagnetic studies are particularly needed.The distribution of mineral deposits (including petroleum) in Ecuador and northwestern Peru is not uniform but is instead related spatially to the five terranes and cratonic South America. This relationship can be useful to prospectors.

Electron probe microanalysis (EPMA) has been used to investigate the mineral assemblage of sand samples from the Venice Lagoon Quaternary sediments. These sediments consist mainly of sand, silt and clay layers with some peat lenses. The boundary between the Holocene and Late-Pleistocene is marked by an overconsolidated layer of clay, related to the origin of the Venetian Lagoon. Because in some area of the basin this clay layer has been eroded away it is not always possible to accurately define the limit between the Holocene and Pleistocene sedimentations.Seventeen continuous cores collected for geotechnical purposes along the offshore sandy bar that separates the Lagoon of Venice from the open Adriatic Sea, were available for this investigation. The cores 25 to 30 m long included the Holocene and Late-Pleistocene sediments. For this preliminary study about 130 sand samples were selected at different depth in order to characterize the various levels of the sediments, recognize and define possible correlations between the layers in the 17 cores and, most important, define the boundary between the Holocene and Pleistocene sediments.

Late Pleistocene organic-rich sediments exposed in coastal bluffs near the head of Plaza Creek, East Falkland, have yielded conventional and AMS 14C dates of between 36 and 28 ka BP, and possess a pollen spectrum dominated by grasses, indicating a vegetation assemblage similar to that of the present day. Although some sample dates are anomalous and contamination by non-contemporaneous carbon cannot be ruled out entirely, the age estimates are consistent with evidence and dates from Antarctica, South America and the amphi-North Atlantic for climate shifts to interstadial conditions at around that time. The organic-rich units are developed in and enclosed by deposits attributed to processes of periglacial mass wasting. Grain-size characteristics suggest that these sediments may have been emplaced by solifluction, shallow translational landsliding and surface wash in at least five mass-wasting episodes. Some of the mass-wasting sediments might correlate with solifluction deposits above and below a podsolic soil dated to 26 ka BP at San Carlos, East Falkland, and with periods of cirque and valley glaciation identified in the uplands of the Falkland Islands. The similarity between late Pleistocene interstadial, Holocene and present-day pollen assemblages, and the lack of vegetation change within these periods, is characteristic of most cool temperate Southern Ocean islands, and may reflect the lack of sensitivity of the vegetation to climate change and/or a lack of climate variability for the time intervals covered. © 1998 John Wiley & Sons, Ltd.

Late Pleistocene organic-rich sediments exposed in coastal bluffs near the head of Plaza Creek, East Falkland, have yielded conventional and AMS 14C dates of between 36 and 28 ka BP, and possess a pollen spectrum dominated by grasses, indicating a vegetation assemblage similar to that of the present day. Although some sample dates are anomalous and contamination by non-contemporaneous carbon cannot be ruled out entirely, the age estimates are consistent with evidence and dates from Antarctica, South America and the amphi-North Atlantic for climate shifts to interstadial conditions at around that time. The organic-rich units are developed in and enclosed by deposits attributed to processes of periglacial mass wasting. Grain-size characteristics suggest that these sediments may have been emplaced by solifluction, shallow translational landsliding and surface wash in at least five mass-wasting episodes. Some of the mass-wasting sediments might correlate with solifluction deposits above and below a podsolic soil dated to 26 ka BP at San Carlos, East Falkland, and with periods of cirque and valley glaciation identified in the uplands of the Falkland Islands. The similarity between late Pleistocene interstadial, Holocene and present-day pollen assemblages, and the lack of vegetation change within these periods, is characteristic of most cool temperate Southern Ocean islands, and may reflect the lack of sensitivity of the vegetation to climate change and/or a lack of climate variability for the time intervals covered. © 1998 John Wiley & Sons, Ltd.

Chapter 23 Heavy-Mineral Provenance in an Estuarine Environment, Willapa Bay, Washington, USA: Palaeogeographic Implications and Estuarine Evolution

ABSTRACTThe dire wolf (Canis dirus) had a broad geographic range in Pleistocene North and South America. Its northernmost occurrence has been reported from late Pleistocene deposits in Medicine Hat, Alberta, representing the only record of the taxon in Canada. However, the dentary upon which these reports were based has never been described or illustrated. The Medicine Hat specimen is badly crushed and appears to be from an old individual, which precludes the observation of adult diagnostic morphological characters. Geometric morphometrics were used to test the previous identification of the Medicine Hat dentary. A landmark‐based principal component analysis and a canonical variates analysis suggests that the specimen more strongly resembles dire wolf specimens than grey wolf (Canis lupus). Identification of the Medicine Hat specimen as C. dirus supports it as the northernmost occurrence of this species in North America. However, we note the potential for allometric relationships that may confound differentiation between grey and dire wolves based on the morphology of the dentary. This study concludes by identifying future work needed in the areas of canid allometry and the biogeography of late Pleistocene North America and Beringia.

Toba Ash on the Indian Subcontinent and Its Implications for Correlation of Late Pleistocene Alluvium

Miocene humid intervals and establishment of drainage networks by 23 Ma in the central Sahara, southern Libya

Deer fauna from Pleistocene and Holocene localities of Ecuador (South America)