Climatic events during the late Pleistocene in New Zealand

Climatic events during the late Pleistocene in New Zealand

Abstracts / Quaternary International 279-280 (2012) 9–120 Sedimentological and geochemical (XRF-scanner) high resolution data of long sediment cores ...

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Abstracts / Quaternary International 279-280 (2012) 9–120

Sedimentological and geochemical (XRF-scanner) high resolution data of long sediment cores (two of 6.93 m and 5,24 m long respectively from La Parra and 4 cores about 18 m from El Tobar) were used to reconstruct the depositional environments, particularly, clastic input, endogenic carbonate deposition, redox evolution and organic productivity. The preliminary chronological model is based on 14C AMS dates of terrestrial macrorests and 210Pb/137Cs dating. The hydrological and geochemical evolution demonstrates a rapid response of the lacustrine systems to anthropogenic and climate forcing during the last 4000 years while highlights differences due to the limnological properties of each lake (holomictic and freshwater versus meromictic and hypersaline) and the importance of the historical uses of the watershed during the MCA and the LIA. The results allow to evaluate the interplays and feedbacks of climate variability in the context of variable human landscapes and activities and enhance our ability to predict the environmental consequences of climate change in Mediterranean mountain areas.

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(w1,000 to w11,700 years ago), Late-Glacial (w11,700 to w15,000 years ago), late to middle Last Glaciation (w15,000 to w45,000 years ago; including Last Glacial Maximum – LGM) and early Last Glaciation and older (> w45,000 years). The map is based on the interpretation of aerial photographs and the field inspection of landforms and associated deposits. It is housed within a Geographic Information System. The digital format allows the production of printed maps as well as data delivery via the internet or other electronic means. The map is a foundation for paleoclimate research, such as dating of moraines, estimation of paleosnowlines, and paleobiologic investigations. The map also offers an observational data input for numerical modelling of glaciers and climate. THE CUEVA DEL ANGEL (LUCENA, SPAIN) - A COMPARATIVE ANALYSIS WITH OTHER END OF MIDDLE TO BEGINNING UPPER PLEISTOCENE SITES OF THE IBERIAN PENINSULA Cecilio Barroso Ruíz. Director of the Cueva del Angel research project, Spain

LESSONS LEARNED FROM THE EARTHQUAKE, NEW ZEALAND

4

SEPTEMBER

2010

DARFIELD

David Barrell. GNS Science, New Zealand E-mail address: [email protected]

The Mw 7.1 Darfield earthquake of 4 September 2010 in Canterbury, New Zealand was the most damaging earthquake to hit New Zealand for nearly 80 years. The level of ground shaking experienced in Christchurch is only expected, on average, once every 500 years or so. Internationally, experts in earthquake science, engineering and disaster response are amazed that no-one was killed and at how quickly the city was functioning again. On a local scale, however, the earthquake has been disruptive to many people and will badly affect many small businesses d it will take a long time for complete recovery. These impacts are largely due to Christchurch having a significant number of old un-reinforced masonry buildings (URM) and having experienced severe ground damage (liquefaction and lateral spreading) in some specific areas. While the fragile nature of some buildings and the presence of vulnerable ground were well known, difficult decisions around retrofitting, where to re-build houses and how to rebuild pipe networks, and where to allow new development, need to be informed by scientific advice. On a longer timeframe the research will influence the future shape of Christchurch. On a national scale, the lessons learned from this earthquake can inform and motivate a much higher degree of resilience across the country through the adoption of new planning and construction approaches d had this earthquake occurred in Wellington, or closer to Christchurch, the impacts would have been much more severe. The scientific findings from this earthquake and its effects will also have a global influence. A GLACIAL GEOMORPHOLOGIC MAP OF THE CENTRAL SOUTH ISLAND OF NEW ZEALAND AND ITS UTILITY FOR PALEOCLIMATE RESEARCH

E-mail address: [email protected]

The Cueva del Angel (Lucena, Spain) site is an archaeological open-air sedimentary sequence remnant of a collapsed cave. It is part of a karst complex that also includes a nearby cavity giving access to a sinkhole (Sima). Six excavations campaigns have generated a considerable amount of archaeological material. Taphonomical characteristics of the herbivore faunal assemblage (dominated by the horse Equus ferus, large bovids and cervids), the well developed final Acheulean industry and a preliminary 230Th/234U date of 121 +11/-10 ky would favor a chronology stretching from the end of the Middle Pleistocene to the beginning of the Upper Pleistocene (MIS 11 to MIS 5). Most of the well known and researched middle Middle Pleistocene Acheulean assemblages of the Iberian Peninsula located in terraces of major rivers would seem to be of an antiquity of ca. 400 ka and may be earlier. The industries of these river terraces are far removed from the one encountered in Cueva del Angel. The sites that would help to clarify where the industry of the Cueva del Angel would fit are to be found in a cave context, such as TG 11 at Atapuerca and Cova del Bolomor in the province of Valencia. From a comparison with the non-Acheulean industry of Bolomor and the Acheulean ensemble of Ambrona with Levallois technology in the upper levels, it is clear that this diversity fits very well with the archaeological evidence encountered in other regions of Western Europe. Thus it would seem that there is no clear boundary between the Lower and Middle Palaeolithic in the Iberian Peninsula, and that tools made on flakes, once considered a feature of the Middle Palaeolithic are common in Acheulean industries, as evidenced in the Cueva del Angel. Thus the Acheulean lithic assemblage found at the Cueva del Angel fits very well with the hypothesis of a continuation of Acheulean cultural traditions in the site resulting in more complex adaptive cultural and behavioral characteristics. CLIMATIC EVENTS DURING THE LATE PLEISTOCENE IN NEW ZEALAND

David Barrell. GNS Science, New Zealand E-mail address: [email protected]

Timothy T. Barrows. University of Exeter, United Kingdom E-mail address: [email protected]

Glaciers produce distinctive landforms and are sensitive indicators of climate change. A magnificent record of glacier landforms is preserved in the middle part of the South Island of New Zealand, within and either side of the Southern Alps. Over the past decade, we have compiled a regional glacial geomorphology map of the central South Island, spanning between the western and eastern coasts of the island, and including the largest modern glaciers of the Southern Alps. This 1:100,000-scale map covers w31,000 square km, and shows modern glaciers as well as differing types of glacier-related landforms (e.g. moraines, moraine ridges, outwash plains and terraces). The map also shows the natures of boundaries between the landforms. Other landforms on the map include alluvial fans, coastal terraces, river floodplains and terraces, beach ridges and landslides. The map gives a broad interpretation of landform ages. Factors such as the degrees of landform preservation, relative positions of landforms in the landscape and available radiometric dates have guided the grouping of landforms according to age. Glacial and fluvial landforms are separated into 5 (calendar) age groups; latest Holocene (< w1,000 years), Holocene

The central West Coast of New Zealand possesses the classic glacial sequence of the late Pleistocene of New Zealand, the most recent advances being broadly grouped as the Otira Glaciation. The current age model of the Otira glaciation is based on radiocarbon dating, and correlation to the marine oxygen isotope record for the oldest (stage 4) advance. The timing of the advances has a distinctly Southern Hemisphere pattern. There are three main glacier advances during the last 35,000 years with deglaciation at 19,000 cal yr BP or shortly after. A brief glacier advance at the beginning of the Holocene is known only from the Waiho Valley below the Franz Josef glacier and there is no advance during the Younger Dryas Chronozone. We have reassessed the limits of ice advance in the lower Taramakau and Arnold River catchments and conducted an exposure dating campaign to place direct age estimates on each of the major glacier limits. We present new ages for these climatic events and explore a potential climate event stratigraphy based on linkages between Southern Hemisphere mid latitude air temperature, sea-surface temperature and Antarctic temperature.