No abstract

No abstract

The Eliki Fault forms part of a system of major normal fault segments that borders the southern margin of the Gulf of Corinth half graben. Radiocarbon dating of elevated marine fossils reveals broadly uniform Holocene coastal uplift, at a time‐averaged rate of 1.5 mm/yr, both along the Eliki Fault and in the transfer zone that separates it from the neighbouring fault segment. Coseismic uplift increments are considered to account for only a minor part of the 6 m of emergence recorded here in the last 3000 years. Reappraisal of shoreline data from the Perachora Peninsula at the eastern end of the Gulf of Corinth indicates a similar, though less rapid (0.7 mm/yr), pattern of uniform Holocene emergence. As these Holocene coastal records embody both coseismic and interseismic deformation they can be used to characterise long‐term tectonic strain.

Volcanic activity has frequently been linked to Quaternary environmental change, either by driving climate modification 1,2 or in response to environmental changes 3 . Although a link has been established between large explosive eruptions and small (0.5 ЊC), brief (1-2 years) falls in global temperatures 4 , both the evidence and mechanisms responsible for longer episodes of eruptioninduced planetary cooling remain questionable 1,2,5,6 . In contrast, recent research based on ice-core data suggests that rapid climate changes during the past 110,000 years increased explosive volcanic activity 7 . Here we present a statistical analysis relating the frequency of explosive activity of Mediterranean volcanoes-based on dated 8-11 tephra layers in deep-sea sediment cores-to the rate of late Quaternary sea-level change. The nonlinear correlation between the two is tentatively explained in terms of dynamic responses of the volcanoes to stress-related influences on various spatial scales. The correlation supports a mechanism or mechanisms by which the climate-driven growth and decay of large ice sheets can influence the eruptive chronologies of distant volcanic edifices via changes in global sea level.The possibility that late Quaternary environmental changes influenced the frequency and magnitude of volcanic eruptions has only recently been considered. New research based on the GISP2 ice core 7 has produced a continuous record of explosive volcanism in the Northern Hemisphere over the past 110 kyr. The record identifies distinct periods of enhanced volcanic activity (notably at 35-22 and 17-6 kyr ago) which coincide with periods of rapid environmental change. In areas where active volcanism 3 and Quaternary glaciation coincide, the correlation between the events can be explained by the effect of changing ice volumes on crustal stresses 12 . In contrast, the effect of ice-sheet volume changes on unglaciated volcanic areas remains problematical. Several authors 6,13-15 have proposed that meltwater loading and unloading could influence volcanic activity at sites distant from areas of ice accumulation through the global redistribution of water, although this hypothesis has never been tested. Here we examine the evidence for a link between such a redistribution and explosive volcanic activity, by comparing the temporal distribution of tephra layers in Mediterranean deep-sea cores 8-11 with established global sea-level curves for the late Quaternary period. All the active volcanic centres in this region ( Fig. 1) either form islands or are adjacent to coastlines, excepting Monte Vulture (Italy) which lies ϳ50 km from the sea.The validity of both the correlation, and the proposed model, is crucially dependent on first, the accuracy with which ages are attributed to individual tephra layers, and second, on limited reworking and resedimentation of the tephra. The available data consist of 81 data layers (both megascopic and determined from a high percentage of volcanic glass in the sediment) in deep-sea cores from the Tyrrhenian 10...

The Gediz (Alaşehir) Graben is located in the highly tectonically active and seismogenic region of Western Turkey. The rivers upstream of the normal faultbounded graben each contain a nonlithologic knickpoint, including those that drain through inferred fault segment boundaries. Knickpoint heights measured vertically from the fault scale with footwall relief and documented fault throw (vertical displacement). Consequently, we deduce these knickpoints were initiated by an increase in slip rate on the basinbounding fault, driven by linkage of the three main fault segments of the highangle graben bounding fault array. Fault interaction theory and ratios of channel steepness suggest that the slip rate enhancement factor on linkage was a factor of 3. We combine this information with geomorphic and structural constraints to estimate that linkage took place between 0.6 Ma and 1 Ma. Calculated pre and postlinkage throw rates are 0.6 and 2 mm/yr respectively. Maximum knickpoint retreat rates upstream of the faults range from 4.5 to 28 mm/yr, faster than for similar catchments upstream of normal faults in the Central Apennines and the Hatay Graben of Turkey, and implying a fluvial landscape response time of 1.6 to 2.7 Myr. We explore the relative controls of drainage area and precipitation on these retreat rates, and conclude that while climate variation and fault throw rate partially explain the variations seen, 5/18/2017 Normal fault growth and linkage in the Gediz (Alaşehir) Graben, Western Turkey, revealed by transient river longprofiles and slopebreak knickpoin… 2/29 lithology remains a potentially important but poorly characterised variable.

No abstract

Most geologists would argue that geoscientific knowledge, experience, and guidance is critical for addressing many of society's most acute environmental challenges, yet few geologists are directly engaged in current discourses around sustainable development. That is surprising given that several attributes make modern geoscience well placed to make critical contributions to contemporary sustainability thinking. Here, we argue that if geoscientists are to make our know-how relevant to sustainability science, two aspects seem clear. Firstly, the geoscience community needs to substantially broaden its constituency, not only forging interdisciplinary links with other environmental disciplines but also drawing from the human and behavioural sciences. Secondly, the principles and practices of 'sustainability' need to be explicitly integrated into geoscience education, training and continued professional development. Dear Editor Many thanks for the opportunity to revise this manuscript based on the two reviews provided. As you noted, the review by Mark Maslin was especially constructive, and we have attempted to weave in most of his broader points. We have also included a specific statement about the extent to which 'sustainability'exists in UK university geoscience departments, although a wider systematic examination of this issue, with real data is beyond the sope of the present article. We have followed your advice and retained the images, although we acknowledge Maslin's comment that they are not essential to the paper. There is some restructuring of the argument to reflect the changes made, and a couple of references have been added, including those indicated by Maslin. Overall we feel that the argument has been sharpened up, though we take heart from the positive endorsements by both referees. I hope you like the new improved version. regards, Iain

No abstract