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1.
Stimulated by the exceeding progress of information technology, the development of mineral exploration has entered a new period of digitization and quantification. The “three components” approach of mineral prediction is suggested as a new approach to the “digital mineral prospecting,” which is based on the geoanomaly analysis, directed by the research on the diversity of mineralization and on the spectrum of mineral deposits. Close combination of these three aspects of quantitative study makes a new starting point to the digital prospecting. In this paper, the basic theories of the “three components” approach of mineral prediction are discussed. In addition, based on the new achievements in the studies on the prediction and assessment of solid minerals and gas–oil resources, we have centered our discussion on the thought of analysis of geoanomaly evolution and on the “5P” method for approaching the target area in the “three components” approach of mineral prediction. 相似文献
2.
K. David Newell 《Natural Resources Research》2007,16(1):55-66
Drill cuttings can be used for desorption analyses but with more uncertainty than desorption analyses done with cores. Drill
cuttings are not recommended to take the place of core, but in some circumstances, desorption work with cuttings can provide
a timely and economic supplement to that of cores. The mixed lithologic nature of drill cuttings is primarily the source of
uncertainty in their analysis for gas content, for it is unclear how to apportion the gas generated from both the coal and
the dark-colored shale that is mixed in usually with the coal. In the Western Interior Basin Coal Basin in eastern Kansas
(Pennsylvanian-age coals), dark-colored shales with normal (∼100 API units) gamma-ray levels seem to give off minimal amounts
of gas on the order of less than five standard cubic feet per ton (scf/ton). In some cuttings analyses this rule of thumb
for gas content of the shale is adequate for inferring the gas content of coals, but shales with high-gamma-ray values (>150
API units) may yield several times this amount of gas. The uncertainty in desorption analysis of drill cuttings can be depicted
graphically on a diagram identified as a “lithologic component sensitivity analysis diagram.” Comparison of cuttings desorption
results from nearby wells on this diagram, can sometimes yield an unique solution for the gas content of both a dark shale
and coal mixed in a cuttings sample. A mathematical solution, based on equating the dry, ash-free gas-contents of the admixed
coal and dark-colored shale, also yields results that are correlative to data from nearby cores. 相似文献
3.
Assessment of Exploration Bias in Data-Driven Predictive Models and the Estimation of Undiscovered Resources 总被引：3，自引：0，他引：3
The spatial distribution of discovered resources may not fully mimic the distribution of all such resources, discovered and
undiscovered, because the process of discovery is biased by accessibility factors (e.g., outcrops, roads, and lakes) and by
exploration criteria. In data-driven predictive models, the use of training sites (resource occurrences) biased by exploration
criteria and accessibility does not necessarily translate to a biased predictive map. However, problems occur when evidence
layers correlate with these same exploration factors. These biases then can produce a data-driven model that predicts known
occurrences well, but poorly predicts undiscovered resources.
Statistical assessment of correlation between evidence layers and map-based exploration factors is difficult because it is
difficult to quantify the “degree of exploration.” However, if such a degree-of-exploration map can be produced, the benefits
can be enormous. Not only does it become possible to assess this correlation, but it becomes possible to predict undiscovered,
instead of discovered, resources.
Using geothermal systems in Nevada, USA, as an example, a degree-of-exploration model is created, which then is resolved into
purely explored and unexplored equivalents, each occurring within coextensive study areas. A weights-of-evidence (WofE) model
is built first without regard to the degree of exploration, and then a revised WofE model is calculated for the “explored
fraction” only. Differences in the weights between the two models provide a correlation measure between the evidence and the
degree of exploration.
The data used to build the geothermal evidence layers are perceived to be independent of degree of exploration. Nevertheless,
the evidence layers correlate with exploration because exploration has preferred the same favorable areas identified by the
evidence patterns. In this circumstance, however, the weights for the “explored” WofE model minimize this bias. Using these
revised weights, posterior probability is extrapolated into unexplored areas to estimate undiscovered deposits. 相似文献
4.
WANG Xiqin ZHANG Yuan LIU Changming 《地理学报(英文版)》2007,17(3):304-316
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that： except Xiliao River is ＂median＂, the rest are all upon ＂good＂, the Dongliao River is even ＂very good＂. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that： considering ＂quantity＂, except Xiliao River, the rest rivers can all achieve the ＂quantity＂ criteria of the en- vironmental flows of river requirements, but if considering the aspect of ＂quality＂, only Dongliao River can reach the ＂quality＂ standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands. 相似文献
5.
Albert A. Bartlett 《Natural Resources Research》2006,15(3):151-164
This paper examines the implications of statements by Australia’s Minister of… Resources that Australia’s exports of coal
are growing rapidly and that Australia’s coal will last “110 years at current rates of production.” If one assumes that coal
production P(t), follows a Gaussian curve (similar to a Hubbert curve) one can construct a family of Gaussian curves showing possible future
paths of P(t) which are consistent with the cited “110 years.” Each curve reaches a maximum after which P(t) declines toward zero. Knowledge of the present value of dP/dt allows one member of the family to be identified as the most probable future path of P(t). Families of curves and tabular data are presented for resource quantities that would last 50, 100 and 200 years “at current
rates of production.” If, instead, Australia’s P(t) follows a declining exponential curve (exp(−kt)) with k = (1/110) per year, the stated quantity of coal will allow production to continue forever, with P(t) declining with a half life of 76 y. This and more rapidly declining exponential paths are the only paths that can be said
to be sustainable. The envelope of the family of Gaussian curves divides the (P, t) plane into “allowed” and “forbidden” areas.
The declining exponential curve divides the “allowed” area into an upper area that is “terminal” and a lower area that is
“sustainable.” These facts, coupled with Australia’s expectations of rapid growth of its population, suggest that Australia’s
present resource policies are “anti-sustainable” and that the people of Australia need to rethink their present policy of
rapidly exporting their fossil fuels. 相似文献
6.
Danilo J. Santini 《Natural Resources Research》1998,7(2):101-121
This paper examines three issues related to both the U.S. and world oil supply: (1) the nature of the long-term, postpeak
production profile for the U.S. and, by inference, other regions (the Hubbert curve is used as a “strawman” model); (2) implications
on U.S. energy security of using a modified Hubbert-type conceptual model of prepeak production, testing the adequacy of Latin
America to be the primary source of U.S. oil imports; and (3) the cyclic behavior of oil prices. it shows that U.S. production
will exhibit a more attenuated decline than that simulated by the Hubbert curve and not decline to zero. it asserts that U.S.
production is better predicted by past reserves than past production, but that this argument does not apply to nations that
keep a much larger proportion of reserves in the ground. Such nations could considerably expand production without any growth
in reserves. The paper concedes that the potential total production for these nations could be examined with a Hubbert curve
model linked to reserves, but with great uncertainty. Such an uncertain optimistic forecast predicts that the cumulative production
of Latin America could far exceed that of the United States. Nevertheless, a statistical model of oil prices since 1870 implies
that real wellhead oil prices in the United States are on a long-term upward path, underlying a much more “noisy” cyclical
pattern estimated to include 22- and 27-year cycles. The statistical model predicts a severe oil shock within a few years
(of 1998) but also predicts that through 2030, real oil prices will not reach 1981 levels again. The paper examines U.S. and
world trends in seismic exploration, drilling locations and depths, drilling costs, oil/gas reserves, oil/gas use rates, and
oil demand. After taking these factors into consideration, it concludes that the statistical model of oil prices cannot be
disputed, despite its lack of basis in economic theory. 相似文献
7.
N. N. Klyuev 《Geography and Natural Resources》2011,32(1):1-8
The concept of territorial justice is developed. The principles of ensuring it are formulated. The method is suggested for
determining the regional dissonances between the manufacture of gross national product and income of the population. The method
offers promise as a necessary coupling tool for identifying potential regions: “donors” and “recipients”. 相似文献
8.
Dyman T. S. Crovelli R. A. Bartberger C. E. Takahashi K. I. 《Natural Resources Research》2002,11(3):207-218
The U.S. Geological Survey recently assessed undiscovered conventional gas and oil resources in eight regions of the world outside the U.S. The resources assessed were those estimated to have the potential to be added to reserves within the next thirty years. This study is a worldwide analysis of the estimated volumes and distribution of deep (>4.5 km or about 15,000 ft), undiscovered conventional natural gas resources based on this assessment. Two hundred forty-six assessment units in 128 priority geologic provinces, 96 countries, and two jointly held areas were assessed using a probabilistic Total Petroleum System approach. Priority geologic provinces were selected from a ranking of 937 provinces worldwide. The U.S. Geological Survey World Petroleum Assessment Team did not assess undiscovered petroleum resources in the U.S. For this report, mean estimated volumes of deep conventional undiscovered gas resources in the U.S. are taken from estimates of 101 deep plays (out of a total of 550 conventional plays in the U.S.) from the U.S. Geological Survey's 1995 National Assessment of Oil and Gas Resources. A probabilistic method was designed to subdivide gas resources into depth slices using a median-based triangular probability distribution as a model for drilling depth to estimate the percentages of estimated gas resources below various depths. For both the World Petroleum Assessment 2000 and the 1995 National Assessment of Oil and Gas Resources, minimum, median, and maximum depths were assigned to each assessment unit and play; these depths were used in our analysis. Two-hundred seventy-four deep assessment units and plays in 124 petroleum provinces were identified for the U.S. and the world. These assessment units and plays contain a mean undiscovered conventional gas resource of 844 trillion cubic ft (Tcf) occuring at depths below 4.5 km. The deep undiscovered conventional gas resource (844 Tcf) is about 17% of the total world gas resource (4,928 Tcf) based on the provinces assessed and includes a mean estimate of 259 Tcf of U.S. gas from the U.S. 1995 National Assessment. Of the eight regions, the Former Soviet Union (Region 1) contains the largest estimated volume of undiscovered deep gas with a mean resource of343 Tcf. 相似文献
9.
V. G. Babin Yu. M. Semenov A. V. Shitov M. G. Sukhova N. A. Kocheeva O. V. Zhuravleva A. I. Minaev A. V. Karanin 《Geography and Natural Resources》2011,32(3):235-241
A case study of the “Ukok Quiet Zone” Natural Park has furnished an opportunity to resolve the related landscape planning
issues trough the use of GIS. The development goals focusing on the geosystem components were assessed and defined, an integral
concept of territorial balanced development was formulated, and the promising long-term areas of nature management were identified. 相似文献
10.
亚洲国际河流研究进展 总被引：4，自引：0，他引：4
1 General situation Entering the 21st century, resource and environmental diplomacy is regarded as a new element for establishing future international patterns of cooperation. Transboundary resources and environmental issues in international river basins … 相似文献
11.
E. D. Attanasi 《Natural Resources Research》1998,7(4):271-279
According to the National Research Council’s Committee on Earth Resources the stated goal of the “sustainability” paradigm
is that the economic activity that maintains current well-being not make future generations worse off, either through environmental
degradation or resource depletion. Coal is not “running out” in the United States but the effects of economic deregulation
of electricity generation, new air quality standards (Phase II of the 1990 Clear Air Act Amendments), and continued restructuring
of the coal mining industry will likely stretch lowsulfur coal supplies in the next decade. The paper discusses these forces
and then presents summary coal quality data in the form of grade-cumulative tonnage relationships for major U.S. producing
areas to show where future low-sulfur coal supplies are likely to come from. The final section considers the potential magnitude
of additional demand for low-sulfur coal, alternative compliance strategies, and implications in terms of maintaining economic
efficiency and in terms of the “sustainability paradigm.” 相似文献
12.
Christian Savu-Krohn Gerd Rantitsch Peter Auer Frank Melcher Torsten Graupner 《Natural Resources Research》2011,20(3):177-191
Two modern machine learning techniques, Linear Programming Boosting (LPBoost) and Support Vector Machines (SVMs), are introduced
and applied to a geochemical dataset of niobium–tantalum (“coltan”) ores from Central Africa to demonstrate how such information
may be used to distinguish ore provenance, i.e., place of origin. The compositional data used include uni- and multivariate
outliers and elemental distributions are not described by parametric frequency distribution functions. The “soft margin” techniques
of LPBoost and SVMs can be applied to such data. Optimization of their learning parameters results in an average accuracy
of up to c. 92%, if spot measurements are assessed to estimate the provenance of ore samples originating from two geographically
defined source areas. A parameterized performance measure, together with common methods for its optimization, was evaluated
to account for the presence of uneven datasets. Optimization of the classification function threshold improves the performance,
as class importance is shifted towards one of those classes. For this dataset, the average performance of the SVMs is significantly
better compared to that of LPBoost. 相似文献
13.
社会生态补偿标准测算方法(英文) 总被引：2，自引：0，他引：2
Ecological compensation is a hot subject in academic studies, and the determina-tion of the spatial allocation of compensation payments is a key point in the research of eco-logical compensation. There are two kinds of thoughts in the determination of regional spatial allocation at present: "evaluation of ecological construction cost" and "evaluation of ecosystem services value". This paper analyzes the relationships between social ecological compensation and regional socio-economic development, and establishes two econometric models with the data of 2007 from various provinces in China. Through these models, the impacts of geographical endowments on the regional socio-economic development in various provinces are analyzed from the social justice viewpoint and the concept of "equivalent value of geographical endowments" (EGE for short) is proposed. This paper analyzes the application prospect of EGE in the policy making of regional ecological compensation. The results showed that: (1) the implementation of social ecological compensation is not only an effective guarantee for each region to obtain the equal rights of survival, development and decent environment, but also an essential assurance to the coordinated, balanced and sustainable development among various regions; (2) the regional difference in geographical endowments is an important factor affecting the regional spatial variation of socio-economic development. Therefore, geographical endowments are important bases for the determination of the spatial allocation of compensation payments in social ecological compensation; (3) based on the EGE, the government can determine the spatial allocation of social ecological compensation scientifically, and avoid the "sweeping approach" phenomenon in the policy making process of ecological compensation. 相似文献
14.
土地利用变化时空模型的图谱方法--以黄河三角洲为例 总被引：12，自引：0，他引：12
Changesinlandcoverandland-usehaveimpactsandimplicationsatlocal,regionalandglobalscalesbecauseofthewaytheyalterbiophysical,biogeochemicalandhydrologicalstatesandprocesses(Alcamoetal.,1996;Li,1996).Since1990,scientistsathomeandabroadhavebeenpayingattentiontoresearchesonland-useandland-coverchange(LUCC)(Turneretal.,1990;MeyerandTurner,1994),butresearchisnotenoughon"spaceandprocess"ofLUCC(Turneretal.,1995).Spatialrelationshipbetweenvariablesyethasnotbeenestablished(Bockstael,1996).Soitispara… 相似文献
15.
A. D. Kalikhman T. P. Kalikhman B. D. Sharastepanov 《Geography and Natural Resources》2011,32(2):172-178
Presented are the results from expedition-based investigations made by the Institute of Geography SB RAS, and an analysis
is made of the economic indices of development of the Okinsky district (Republic of Buryatia), which made it possible to draw
a preliminary conclusion about the formation of the ecological tourism structure on the territory of Gornaya Oka and provide
a rationale for the establishment of the “Gornaya Oka” natural park as a necessary and legislatively supported territory designed
for rational and controlled utilization of tourist and recreational resources. 相似文献
16.
Defining the reference state of some perturbed streams and rivers is challenging since their non-altered state is undocumented.
Despite the near-absence of pristine sites in highly anthropogenic areas, information about aquatic communities that existed
prior to human disturbance can be obtained from historic sources. Sediment coring is commonly used in paleolimnology to estimate
past environmental conditions of lakes, but this technique is often not appropriate for studies of lotic systems. An alternative
is to use diatom assemblages present in the guts of fish that were captured in the streams prior to significant human disturbance.
The purpose of the present study was to evaluate the biological integrity of several streams in Ontario and Québec during
the early twentieth century based on “paleo” diatom assemblages extracted from the guts of fish stored in museums. The Eastern
Canadian diatom index (IDEC: Indice Diatomées de l’Est du Canada) was used to evaluate the biological status of “paleo” and
“modern” diatom assemblages. The IDEC shows the position of diatom assemblages on a general pollution gradient. The comparison
of IDEC values calculated for the 1925–1948 and the 2003–2007 periods showed that several streams were severely polluted in
the early 1900s. In general, present water quality has declined compared to the early 1900s. The biological integrity of only
three of the 22 sites has increased. IDEC values were not influenced by the species of fish studied. 相似文献
17.
Unlike other branches of geosciences, exploratory drilling has not been investigated within the framework of an information
system; so, the expression “value of exploratory drilling information” (despite its common usage) is vague. This article presents
a model for the evaluation of value of the information gathered from exploratory drilling after studying different mineral
exploration and exploratory drilling systems within the framework of an “information system.” Although this model does not
present the economic value of information, it is a suitable tool for comparing different drilling patterns. The model was
verified on the basis of drilling data for the Gol-Gohar XIIA anomaly. 相似文献
18.
Barbara Białecka 《Natural Resources Research》2008,17(1):21-28
One of the prospective methods of coal utilization, especially in case of coal resources which are not mineable by means of
conventional methods, is underground coal gasification (UCG). This technology allows recovery of coal energy “in situ” and
thus avoid the health and safety risks related to people which are inseparable from traditional coal extraction techniques.
In Poland most mining areas are characterized by numerous coal beds where extraction was ceased on account of technical and
economic reasons or safety issues. This article presents estimates of Polish hard coal resources, broken down into individual
mines, that can constitute the basis of raw materials for the gasification process. Five mines, representing more than 4 thousand
tons, appear to be UCG candidates. 相似文献
19.
Two widely-used techniques to estimate the volume of remaining oil and gas resources are discovery process modeling and geologic assessment. Both were used in a recent national assessment of oil and gas resources of the United States. Parallel estimates were obtained for 27 provinces. Geological-based estimates can typically see into areas not available to discovery process models (that is areas with little or no exploration history) and thus, on average, yield higher estimates. However, a linear relation does exist between the mean estimates obtained from these two methods. In addition, other variables were found in a multiple regression model that explained much of the difference. Thus, it is possible to perform discovery process modeling and adjust the estimates to yield results that might be expected from geological-based assessments. 相似文献
20.
An oases dynamics model and its application in the Manas oasis 总被引：2，自引：0，他引：2
This study applies theories of systems and system dynamics to ecological economic systems in the oasis environment, with the
intention of finding the basic characteristics of the oasis environment and its feedback structures. This study explores the
inner mechanisms of economic development in the oasis environment and its relationship to policy variables. This model is
applied to economic development in the Manas oasis of the Xinjiang Uygur Autonomous Region of China. System dynamics method
starts from studying feedback structure within the system study and then searches for the best solution through identifying
the right “policy point” and through model simulation in the computer. It embodies the cream of “systems cybernetics theory”.
This study is justified because the nature of the oasis system and the simulation results are scientifically sound and practically
feasible. 相似文献