New data on the most ancient early quaternary glaciation in Gornyi Altai

The data presented in this work introduce substantial corrections into the Upper Cenozoic stratigraphy and geological history of Gornyi Altai. They provide evidence for the most ancient Early Pleistocene glaciation in this region. This follows from finds of faceted boulders buried in the Bashkaus Formation. Pale-omagnetic investigations revealed in the latter a wide zone of negative polarity corresponding to the Matuyama Chron in the magnetostratigraphic scale and made it possible to correlate the formation with the Lower Pleistocene in the standard stratigraphic scale. It is shown that global cooling at the beginning of the Quaternary Period stimulated development of glaciation on the southern slope of the Kuraiskii Range exceeding in size its present-day scale.     

Seismogenic destruction of the Kamenka medieval fortress, northern Issyk-Kul region, Tien Shan (Kyrgyzstan)

A paleoseismological study of the medieval Kamenka fortress in the northern part of the Issyk-Kul Lake depression, northern Tien Shan in Kyrgyzstan, revealed an oblique slip thrust fault scarp offsetting the fortification walls. This 700 m long scarp is not related to the 1911 Kebin Earthquake (Ms 8.2) fault scarps which are widespread in the region. As analysis of stratigraphy in a paleoseismic trench and archaeological evidence reveal, it can be assigned to a major twelfth century a.d. earthquake which produced up to 4 m of oblique slip thrusting antithetic to that of the nearby dominant faults. The inferred surface rupturing earthquake apparently caused the fortress destruction and was likely the primary reason for its abandonment, not the Mongolian–Tatar invasions as previously thought.     

Geodynamic models and their application in the combined interpretation of geological and geophysical data (a review)

The paper presents a review of investigations in the field of the theory and practice of the interpretation of geological and geophysical data with geodynamic models that were carried out mainly by researchers of the Institute of Physics of the Earth, Russian Academy of Sciences. Evolutionary models of platform structures, passive continental margins, rift zones, and orogens are examined. The review presents formulations of inverse problems and results of interpretation for various regions, including sedimentary basins of the East European Platform, Atlantic Ocean margins, the Caucasus, the South Urals, and others.     

Environmental changes in the northern Altai during the last millennium documented in Lake Teletskoye pollen record

A high-resolution pollen record from Lake Teletskoye documents the climate-related vegetation history of the northern Altai Mountain region during the last millennium. Siberian pine taiga with Scots pine, fir, spruce, and birch dominated the vegetation between ca. AD 1050 and 1100. The climate was similar to modern. In the beginning of the 12th century, birch and shrub alder increased. Lowered pollen concentrations and simultaneous peaks in herbs (especially Artemisia and Poaceae), ferns, and charcoal fragments point to colder and more arid climate conditions than before, with frequent fire events. Around AD 1200, regional climate became warmer and more humid than present, as revealed by an increase of Siberian pine and decreases of dry herb taxa and charcoal contents. Climatic conditions were rather stable until ca. AD 1410. An increase of Artemisia pollen may reflect slightly drier climate conditions between AD 1410 and 1560. Increases in Alnus, Betula, Artemisia, and Chenopodiaceae pollen and in charcoal particle contents may reflect further deterioration of climate conditions between AD 1560 and 1810, consistent with the Little Ice Age. After AD 1850 the vegetation gradually approached the modern one, in conjunction with ongoing climate warming.     

Debatable aspects of initial human colonization of Siberia and age of the Karama site in the Altai Mountains

Debatable aspects of age, stratigraphic position, and natural conditions of the oldest stratified Early Paleolithic Karama site in the Altai Mountains are critically revised. The extensive geological, stratigraphic, and paleontological data allow the sufficiently well-substantiated assumption that accumulation of the Karama Formation and existence of the Early Paleolithic Karama site correspond to a long period of climate warming in the Early Pleistocene correlated with the Tiglian of northwestern Europe lasting from 2.23 to 1.59 Ma. The age model proposed for the formation of the Quaternary sequence in the Anui River valley, which includes the artifact-containing deposits of the Karama site, seems to be the most probable one proceeding from interpretation of available data on the geological structure, stratigraphy, paleomagnetism, and paleontological and lithological properties of Upper Cenozoic sequences observable both in the Anui River valley and in Siberian areas adjacent to the Altai mountainous region.     

Time patterns of magmatic ore systems in circum-Pacific volcanoplutonic belts

Integrate statistical processing of more than 1000 isotope dates tracing the history of circum-Pacific magmatic ore systems and related mineral deposits in volcanoplutonic belts allows the following inferences: (1) magmatic ore systems (MOS) of volcanic arcs generate monoand polycyclic volcanoplutonic deposits (VPD) with notably different formation times (longevities); (2) the MOS chronology bears periodicity of events in the post-Paleozoic history of the Pacific continental margin; (3) the time series of magmatic ore systems from different circum-Pacific segments show quasi-periodic patterns but the respective metallogenic epochs within the same time intervals have different phases and amplitudes, especially over the past 30 Myr; (4) each mineral type of VPD has its own periodicity; (5) the periodicity in formation times of mono- and polycyclic VPD differs from that in the times of their origin.     

Multichannel rivers: their definition and classification

The etymology and historic usage of such terms as ‘anabranch’, ‘anastamose’ and ‘braided’ within river science are reviewed. Despite several decades of modern research to define river channel typologies inclusive of single channels and multiple channel networks, typologies remain ill‐conditioned and consequently ill‐defined. Conventionally employed quantitative planform characteristics of river networks possibly cannot be used alone to define channel types, yet the planform remains a central part of all modern classification schemes, supplemented by sedimentological and other qualitative channel characteristics. Planform characteristics largely have been defined using non‐standardized metrics describing individual network components, such as link lengths, braiding intensity and bifurcation angles, which often fail to separate visually‐different networks of channels. We find that existing typologies remain pragmatically utilitarian rather than fundamentally physics‐based and too often fail to discriminate between two distinctive and important processes integral to new channel initiation and flow‐splitting: (i) in‐channel bar accretion, and (ii) channel avulsion and floodplain excision. It is suggested that, first, if channel planform is to remain central to river typologies, then more rigorous quantitative approaches to the analysis of extended integral channel networks at extended reach scales (rather than network components) are required to correctly determine whether ‘visually‐different’ channel patterns can be discriminated consistently; and, second, if such visually‐different styles do in fact differ in their governing processes of formation and maintenance. A significant question is why do so many seemingly equilibrium network geometries possess a large number of anabranches in excess of predictions from theoretical considerations? The key research frontier with respect to initiating and maintaining multichannel networks remains the understanding and discrimination of accretionary‐bar flow splitting versus avulsive processes. Existing and new knowledge on flow splitting processes needs to be better integrated into channel typologies. Copyright © 2013 John Wiley & Sons, Ltd.     

A preliminary investigation of fossil wood from Lower Mekong Basin of Southeast Asia

Nine fossil wood samples from the Mesozoic bedrock and the Quaternary terrace deposits of the Lower Mekong Basin in Southeast Asia including Thailand , Laos and Cambodia were investigated in order to assist in developing a hypothesis about the Mekong River palaeocourses .Six of the samples were conifers assigned to Aga-thoxylon sp., and three were dicots of cf .Pahudioxylon sp.and two unknown taxa ( Dicotyloxylon sp.) . The preservation of two dicotyledonous wood samples is insufficient for precise identification to family level , such that the samples are not suitable with respect to investigation of the river palaeocourse .However , these findings increase the systematic data of the fossil wood from the Mekong Basin .Further investigations of fossil wood from the Mekong Basin are in progress to gain a regional perspective on the plant communities and to form better reconstruction of the palaeoenvironment .     

Natural periodic processes and climate variability in the Northern Hemisphere

Decomposition of five different paleoclimatic reconstructions of regional and hemispheric scale into different frequency periodic components has been performed for the extratropical zone of the Northern Hemisphere using spectral analysis methods (Hilbert–Huang transformation, wavelet transform, Fourier transform). The presence of ~1000, ~500, ~350, and ~200-year quasi-cyclic periodicities has been established, which determines climatic variability over the last 2–4 millennia. The presence of similar cyclicities, manifested in climatic and other geological processes, has been noted by many researchers and has been explained, as a rule, by changes in solar insolation. Thus, there is every reason to believe that the revealed quasi-periodic components in the climate variability of the extratropical zone of the Northern Hemisphere are natural, conditioned by natural cyclical phenomena and can serve as a basis for long-term predictive climatic constructions.

     

Transfers and environmental co-benefits of carbon sequestration in agricultural soils: retiring agricultural land in the Upper Mississippi River Basin

This study investigates the carbon sequestration potential and co-benefits from policies aimed at retiring agricultural land in the Upper Mississippi River Basin, a large, heavily agricultural area. In addition to empirically measuring environmental co-benefits, we also compute economic transfers, which have sometimes been referred to as a co-benefit. Very little empirical work measuring the potential magnitude of these transfers has previously been undertaken. We compare and contrast alternative targeting schemes. We find that there are considerable amount of co-benefits and transfers and that the geographic distribution of co-benefits and transfers varies significantly with the specific benefit targeted. This implies that policy design related to targeting can have very important implications for both environmental conditions and income distributions in sub-regions. Issues related to policy design in the presence of co-benefits are considered. Senior authorship is shared equally between the first two authors. All views are those of the authors and not necessarily the funding agencies.