Quechua II contraction in the Ayacucho intermontane basin: Evidence for rapid and episodic Neogene deformation in the Andes of central Perú     

James M. Wise  Donald C. Noble  Kathleen A. Zanetti  Terry L. Spell 《Journal of South American Earth Sciences》2008,26(4):383-396

In the Ayacucho basin of central Perú the regional Quechua II contractional deformation is bracketed by ⁴⁰Ar/³⁹Ar isotopic age determinations to a maximum duration of about 300,000 years, and probably less than 150,000 years, centered on 8.7 Ma. The strongly deformed Huanta Formation beneath the Quechua II angular unconformity was deposited during a period of extension that began before 9.05 ± 0.05 Ma. Deposition of a thick succession of alluvial fan deposits interbedded with flows of basaltic andesite in the Tingrayoc Member continued up to about 8.76 ± 0.05 Ma with the later part of the sedimentary record reflected by lacustrine deposits of the Mayocc Member. The upper limit on contractional deformation is constrained by an age of 8.64 ± 0.05 Ma on a unit of tuff near the base of the Puchcas volcanics, which in places was deposited upon near-vertical beds of the Huanta Formation. The Ayacucho Formation was deposited, locally unconformably, upon the Puchcas volcanics beginning slightly before 7.65 ± 0.10 Ma.Extended periods of neutral to tensional stress interrupted by rapid well-developed pulses of contractional deformation demonstrate the episodic behavior of Andean orogeny in Perú. The very short duration for the Quechua II event implies that driving forces for episodic deformation may be related to coupling along the orogen boundaries and strain accumulation and release mechanisms in the continental crust instead of much longer-term variations in the configuration of converging plates.  相似文献   

Long-term Spatially Distributed Solutional Erosion: How Do We Put Solutes on the Map?     

Stephen Trudgill  Stephen Wise 《地球表面变化过程与地形》1997,22(3):281-285

Much of the short-term solute process research in the last 20 years has focused on hydrochemical behaviour. This can help with the identification of solute source area type, but not the actual location of the solutional loss. The location and the spatial distribution of erosion are crucial to the identification of long-term landscale evolution. The way ahead lies in the fact that catchment budgeting and geochemical studies have been able to provide solute uptake rates. If these can be related to soil type, through a knowledge of soil mineralogy, reactive surface area and water flow rate, it may be possible to characterize the location and spatial distribution of solutional erosion through terrain analysis and soil maps in a geographical information system. © 1997 by John Wiley & Sons, Ltd.  相似文献   

Extracting raster GIS data from scanned thematic maps     

Stephen Wise 《Transactions in GIS》1999,3(3):221-237

One of the problems which continues to trouble practical applications of GIS is the time and cost of capturing data from paper maps. Even where the data are required in raster form the complexity of most maps means that the data are first digitised in vector form, and then rasterised, a slow and error-prone process. This paper describes an alternative approach based upon readily available hardware and software in which the map is scanned using Spot Colour Scanning, and then processed using a specially designed majority filter and editing with a painting package. Tests on a small scale soil map produce results which are about 80% as accurate as digitising, but take far less time to produce. An analysis of the sources of error indicates that many of these are due to the difficulty of scanning such a complex document as a map, and suggests that more sophisticated image processing algorithms may be needed to classify the original scanned image before the application of the filter algorithm.  相似文献   

Strike-slip fault-propagation cleavage in carbonate rocks: the Mattinata Fault Zone, Southern Apennines, Italy     

Francesco Salvini  Andrea Billi  Donald U. Wise 《Journal of Structural Geology》1999,21(12):1315

Disjunctive, spaced solution cleavage in carbonate rocks is genetically associated with the propagation of the left-lateral, strike-slip Mattinata Fault in the Gargano Promontory, Italy. Typical cleavage development is restricted within the 200–300-m wide fault zone, which is bounded by virtually unfractured wall rocks. The cleavage consists of sub-parallel solution surfaces, which are often reactivated as sheared solution planes. Geometrical and kinematic relationships exist between the fault and the associated cleavage planes, thus: (1) cleavage–fault intersection lines lie parallel to the fault and the sheared cleavage rotational axes and (2) the cleavage–fault angle is almost constantly equal to 40°. A model for the development of the Mattinata Fault is proposed in which the cleavage surfaces are interpreted as fault-propagation deformations. Cleavage nucleates as solution planes at the front of the advancing fault as the result of stress concentration in this region. Two distinct, time-sequential processes are shown to operate during the fault propagation: (1) typical millimetre- to centimetre-spaced solution surfaces form in the distal tip zone of the advancing fault plane; (2) as the tip advances, the fault plane breaks through the cleavage as minor shear displacements reactivate some of these nascent surfaces. These observations may prove useful in understanding mechanisms for fault-controlled enhanced/reduced permeability and fluid pathways.  相似文献   

Designing and implementing software for spatial statistical analysis in a GIS environment   总被引：4，自引：0，他引：4  

Robert Haining  Stephen Wise  Jingsheng Ma 《Journal of Geographical Systems》2000,2(3):257-286

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Providing spatial statistical data analysis functionality for the GIS user: the SAGE project     

Stephen Wise  Robert Haining  Jingsheng Ma 《International journal of geographical information science》2013,27(3):239-254

Geographic representation has become more complex through time as researchers have added new concepts, leading to apparently endless proliferation and creating a need for simplification. We show that many of these concepts can be derived from a single foundation that we term the atomic form of geographic information. The familiar concepts of continuous fields and discrete objects can be derived under suitable rules applied to the properties and values of the atomic form. Fields and objects are further integrated through the concept of phase space, and in the form of field objects. A second atomic concept is introduced, termed the geo‐dipole, and shown to provide a foundation for object fields, metamaps, and the association classes of object‐oriented data modelling. Geographic dynamics are synthesized in a three‐dimensional space defined by static or dynamic object shape, the possibility of movement, and the possibility of dynamic internal structure. The atomic form also provides a tentative argument that discrete objects and continuous fields are the only possible bases for geographic representation.  相似文献   

Can radiative forcing be limited to 2.6 Wm−2 without negative emissions from bioenergy AND CO2 capture and storage?     

James Edmonds  Patrick Luckow  Katherine Calvin  Marshall Wise  Jim Dooley  Page Kyle  Son H. Kim  Pralit Patel  Leon Clarke 《Climatic change》2013,118(1):29-43

Combining bioenergy and carbon dioxide (CO₂) capture and storage (CCS) technologies (BECCS) has the potential to remove CO₂ from the atmosphere while producing useful energy. BECCS has played a central role in scenarios that reduce climate forcing to low levels such as 2.6 Wm^?2. In this paper we consider whether BECCS is essential to limiting radiative forcing (RF) to 2.6 Wm^?2 by 2100 using the Global Change Assessment Model, a closely coupled model of biogeophysical and human Earth systems. We show that BECCS can potentially reduce the cost of limiting RF to 2.6 Wm^?2 by 2100 but that a variety of technology combinations that do not include BECCS can also achieve this goal, under appropriate emissions mitigation policies. We note that with appropriate supporting land-use policies terrestrial sequestration could deliver carbon storage ranging from 200 to 700 PgCO₂-equiavalent over the 21st century. We explore substantial delays in participation by some geopolitical regions. We find that the value of BECCS is substantially higher under delay and that delay results in higher transient RF and climate change. However, when major regions postponed mitigation indefinitely, it was impossible to return RF to 2.6 Wm^?2 by 2100. Neither finite land resources nor finite potential geologic storage capacity represented a meaningful technical limit on the ability of BECCS to contribute to emissions mitigation in the numerical experiments reported in this paper.  相似文献   

Trade-offs of different land and bioenergy policies on the path to achieving climate targets     

Katherine Calvin  Marshall Wise  Page Kyle  Pralit Patel  Leon Clarke  Jae Edmonds 《Climatic change》2014,123(3-4):691-704

Many papers have shown that bioenergy and land-use are potentially important elements in a strategy to limit anthropogenic climate change. But, significant expansion of bioenergy production can have a large terrestrial footprint. In this paper, we test the implications for land use, the global energy system, emissions and mitigation costs of meeting a specific climate target, using a single fossil fuel and industrial sector policy instrument, but with five alternative bioenergy and land-use policy architectures. These scenarios are illustrative in nature, and designed to explore trade-offs. We find that the policies we examined have differing effects on the different segments of the economy. Comprehensive land policies can reduce land-use change emissions, increasing allowable emissions in the energy system, but have implications for the cost of food. Bioenergy penalties and constraints, on the other hand, have little effect on food prices, but result in less bioenergy and thus can increase mitigation costs and energy prices.  相似文献   

The effects of climate sensitivity and carbon cycle interactions on mitigation policy stringency     

Katherine Calvin  Ben Bond-Lamberty  James Edmonds  Mohamad Hejazi  Stephanie Waldhoff  Marshall Wise  Yuyu Zhou 《Climatic change》2015,131(1):35-50

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Shrimping as a source of suspended sediment in Corpus Christi Bay (Texas)     

J. R. Schubel  H. H. Carter  W. M. Wise 《Estuaries and Coasts》1979,2(3):201-203

Our field study showed that the total amount of sediment disturbed in Corpus Christi Bay each year by shrimp trawling is 10-100 times greater than that dredged in an average year for maintenance of shipping channels. The maximum concentrations of suspended sediment measured in the trails of the shrimp boats were comparable of the dredge operating in the same area. of 3% is obtained.  相似文献