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Page 1: Lessons learned from the 4 September 2010 Darfield earthquake, New Zealand

Abstracts / Quaternary International 279-280 (2012) 9–120 41

Sedimentological and geochemical (XRF-scanner) high resolution data oflong sediment cores (two of 6.93 m and 5,24 m long respectively from LaParra and 4 cores about 18 m from El Tobar) were used to reconstruct thedepositional environments, particularly, clastic input, endogenic carbonatedeposition, redox evolution and organic productivity. The preliminarychronological model is based on 14C AMS dates of terrestrial macrorestsand 210Pb/137Cs dating. The hydrological and geochemical evolutiondemonstrates a rapid response of the lacustrine systems to anthropogenicand climate forcing during the last 4000 years while highlights differencesdue to the limnological properties of each lake (holomictic and freshwaterversus meromictic and hypersaline) and the importance of the historicaluses of the watershed during the MCA and the LIA. The results allow toevaluate the interplays and feedbacks of climate variability in the contextof variable human landscapes and activities and enhance our ability topredict the environmental consequences of climate change in Mediterra-nean mountain areas.

LESSONS LEARNED FROM THE 4 SEPTEMBER 2010 DARFIELDEARTHQUAKE, NEW ZEALAND

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

The Mw 7.1 Darfield earthquake of 4 September 2010 in Canterbury, NewZealand was the most damaging earthquake to hit New Zealand for nearly80 years. The level of ground shaking experienced in Christchurch is onlyexpected, on average, once every 500 years or so. Internationally, expertsin earthquake science, engineering and disaster response are amazed thatno-one was killed and at how quickly the city was functioning again. Ona local scale, however, the earthquake has been disruptive to many peopleand will badly affect many small businesses d it will take a long time forcomplete recovery. These impacts are largely due to Christchurch havinga significant number of old un-reinforced masonry buildings (URM) andhaving experienced severe ground damage (liquefaction and lateralspreading) in some specific areas. While the fragile nature of somebuildings and the presence of vulnerable ground were well known, diffi-cult decisions around retrofitting, where to re-build houses and how torebuild pipe networks, and where to allow new development, need to beinformed by scientific advice. On a longer timeframe the research willinfluence the future shape of Christchurch. On a national scale, the lessonslearned from this earthquake can inform and motivate a much higherdegree of resilience across the country through the adoption of newplanning and construction approaches d had this earthquake occurred inWellington, or closer to Christchurch, the impacts would have been muchmore severe. The scientific findings from this earthquake and its effectswill also have a global influence.

A GLACIAL GEOMORPHOLOGIC MAP OF THE CENTRAL SOUTH ISLANDOF NEW ZEALAND AND ITS UTILITY FOR PALEOCLIMATE RESEARCH

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

Glaciers produce distinctive landforms and are sensitive indicators ofclimate change. A magnificent record of glacier landforms is preserved inthe middle part of the South Island of New Zealand, within and eitherside of the Southern Alps. Over the past decade, we have compileda regional glacial geomorphology map of the central South Island,spanning between the western and eastern coasts of the island, andincluding the largest modern glaciers of the Southern Alps. This1:100,000-scale map covers w31,000 square km, and shows modernglaciers as well as differing types of glacier-related landforms (e.g.moraines, moraine ridges, outwash plains and terraces). The map alsoshows the natures of boundaries between the landforms. Other land-forms on the map include alluvial fans, coastal terraces, river floodplainsand terraces, beach ridges and landslides. The map gives a broad inter-pretation of landform ages. Factors such as the degrees of landformpreservation, relative positions of landforms in the landscape andavailable radiometric dates have guided the grouping of landformsaccording to age. Glacial and fluvial landforms are separated into 5(calendar) age groups; latest Holocene (< w1,000 years), Holocene

(w1,000 to w11,700 years ago), Late-Glacial (w11,700 to w15,000 yearsago), late to middle Last Glaciation (w15,000 to w45,000 years ago;including Last Glacial Maximum – LGM) and early Last Glaciation andolder (> w45,000 years). The map is based on the interpretation of aerialphotographs and the field inspection of landforms and associateddeposits. It is housed within a Geographic Information System. The digitalformat allows the production of printed maps as well as data delivery viathe internet or other electronic means. The map is a foundation forpaleoclimate research, such as dating of moraines, estimation of paleo-snowlines, and paleobiologic investigations. The map also offers anobservational data input for numerical modelling of glaciers and climate.

THE CUEVA DEL ANGEL (LUCENA, SPAIN) - A COMPARATIVE ANALYSISWITH OTHER END OF MIDDLE TO BEGINNING UPPER PLEISTOCENESITES OF THE IBERIAN PENINSULA

Cecilio Barroso Ruíz. Director of the Cueva del Angel research project, SpainE-mail address: [email protected]

The Cueva del Angel (Lucena, Spain) site is an archaeological open-airsedimentary sequence remnant of a collapsed cave. It is part of a karstcomplex that also includes a nearby cavity giving access to a sinkhole(Sima). Six excavations campaigns have generated a considerable amountof archaeological material. Taphonomical characteristics of the herbivorefaunal assemblage (dominated by the horse Equus ferus, large bovids andcervids), the well developed final Acheulean industry and a preliminary230Th/234U date of 121 +11/-10 ky would favor a chronology stretchingfrom the end of the Middle Pleistocene to the beginning of the UpperPleistocene (MIS 11 to MIS 5). Most of the well known and researchedmiddle Middle Pleistocene Acheulean assemblages of the Iberian Penin-sula located in terraces of major rivers would seem to be of an antiquity ofca. 400 ka and may be earlier. The industries of these river terraces are farremoved from the one encountered in Cueva del Angel. The sites thatwould help to clarify where the industry of the Cueva del Angel would fitare to be found in a cave context, such as TG 11 at Atapuerca and Cova delBolomor in the province of Valencia.From a comparison with the non-Acheulean industry of Bolomor and theAcheulean ensemble of Ambrona with Levallois technology in the upperlevels, it is clear that this diversity fits very well with the archaeologicalevidence encountered in other regions of Western Europe. Thus it wouldseem that there is no clear boundary between the Lower and MiddlePalaeolithic in the Iberian Peninsula, and that tools made on flakes, onceconsidered a feature of the Middle Palaeolithic are common in Acheuleanindustries, as evidenced in the Cueva del Angel. Thus the Acheulean lithicassemblage found at the Cueva del Angel fits very well with thehypothesis of a continuation of Acheulean cultural traditions in the siteresulting in more complex adaptive cultural and behavioral character-istics.

CLIMATIC EVENTS DURING THE LATE PLEISTOCENE IN NEW ZEALAND

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

The central West Coast of New Zealand possesses the classic glacialsequence of the late Pleistocene of New Zealand, the most recentadvances being broadly grouped as the Otira Glaciation. The current agemodel of the Otira glaciation is based on radiocarbon dating, and corre-lation to the marine oxygen isotope record for the oldest (stage 4)advance. The timing of the advances has a distinctly Southern Hemi-sphere pattern. There are three main glacier advances during the last35,000 years with deglaciation at 19,000 cal yr BP or shortly after. A briefglacier advance at the beginning of the Holocene is known only from theWaiho Valley below the Franz Josef glacier and there is no advance duringthe Younger Dryas Chronozone. We have reassessed the limits of iceadvance in the lower Taramakau and Arnold River catchments and con-ducted an exposure dating campaign to place direct age estimates on eachof the major glacier limits. We present new ages for these climatic eventsand explore a potential climate event stratigraphy based on linkagesbetween Southern Hemisphere mid latitude air temperature, sea-surfacetemperature and Antarctic temperature.

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