Prospectivity Mapping for Porphyry Cu–Mo Mineralization in the Eastern Tianshan,Xinjiang, Northwestern China

Natural Resources Research - In order to comprehensively utilize regional-scale geological, geochemical and geophysical datasets for future exploration of undiscovered porphyry Cu–Mo...     

Competing Place Meanings in Complex Landscapes: A Social–Ecological Approach to Unpacking Community Conservation Outcomes on the Wild Coast,South Africa

Despite a general awareness of the social–ecological complexities within which conservation interventions are embedded, approaches to understanding a diversity of local perspectives of heterogeneous landscapes and how they matter for the outcomes of these interventions are seldom demonstrated. We apply a social–ecological approach to exploring the multiple place meanings related to key landscape elements around a proposed community conservation intervention on the Wild Coast, South Africa, by identifying and analyzing three narratives about this impending change. These narratives mobilize competing meanings of the landscape to argue for or against the conservation project. By linking place meanings to locally defined landscape units (ecotopes), we engage multiple interpretations of the heterogeneous and changing landscape to gain a holistic and more inclusive picture of social–ecological landscape processes such as increasing woodlands and field abandonment. The obstruction of this particular intervention indicates the importance of engaging with multiple cultural values of nature.     

An AHP–TOPSIS Predictive Model for District-Scale Mapping of Porphyry Cu–Au Potential: A Case Study from Salafchegan Area (Central Iran)

The Salafchegan area in central Iran is a greenfield region of high porphyry Cu–Au potential, for which a sound prospectivity model is required to guide mineral exploration. Satellite imagery, geological geochemical, geophysical, and mineral occurrence datasets of the area were used to run an innovative integration model for porphyry Cu–Au exploration. Five favorable multi-class evidence maps, representing diagnostic porphyry Cu–Au recognition criteria (intermediate igneous intrusive and sub-volcanic host rocks, structural controls, hydrothermal alterations, stream sediment Cu anomalies, magnetic signatures), were combined using analytic hierarchy process and technique for order preference by similarity to ideal solution to calculate a final map of porphyry Cu–Au potential in the Salafchegan area.     

Computer Expert System for Epithermal Gold-Silver Deposit Prognostication (Okhotsk–Chuckchee Volcanic Belt,Northeast Russia)

The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an expert system (solution tree) was compiled. The computer system is intended to be an assistance to an expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.     

Varves in a Proglacial Lake,Sermilik, South East Greenland/Meterological Observations at Arctic Station,Qeqertarsuaq (Godhavn), Central West Greenland/Den Danske Nationalkomité for Geografi 1994–95

Danish Journal of Geography 95: 92–96, 1995.

Three cores collected from a proglacial lake with an Axelsson corer are x-rayed. The stratification is interpreted as varves. The cores cover periods of sedimentation with a duration from 5—23 years. The average thickness of the varves vary from 1.9—20.0 mm indicating a tenfold variation in the sedimentation rate.

Geografisk Tidsskrift 96: 97–104, 1995.

In October 1990 a new automatic meteorological station was established at the Arctic Station, Qeqertarsuaq (Godhavn), managed by the University of Copenhagen. It is the purpose of this note to draw the attention to the existence of this meteorological station, the character of climate parameter monitored and to the environment in which the station is functioning.

Examples of climate data measured during 1994 are presented, and general trends in the fluctuation of the selected parameters are annotated. Furthermore, it is mentioned how users may obtain the climate data. In the years to come we plan to publish a similar status of the climatic development at the Arctic Station in this periodical.     

Extraction of Mineralization-Related Anomalies from Gravity and Magnetic Potential Fields for Mineral Exploration Targeting: Tongling Cu(–Au) District,China

Natural Resources Research - Extraction of mineralization-related anomalies for mineral exploration targeting lies in the interpretation of geological anomalies that indicate favorable ore-forming...     

Elemental (C,N, H and P) and stable isotope (δ<Superscript>15</Superscript>N and δ<Superscript>13</Superscript>C) signatures in sediments from Zeekoevlei,South Africa: a record of human intervention in the lake

We used elemental carbon, nitrogen, phosphorus and hydrogen ratios (C/N, N/P and H/C) with total organic carbon (TOC) and total phosphorus (TP) as well as stable carbon and nitrogen isotopes (δ¹³C and δ¹⁵N) to investigate the source and depositional conditions of organic matter in sediments from Zeekoevlei, the largest freshwater lake in South Africa. Typical C/N (10–12), H/C ratios (≥1.7) and δ¹³C_organic values (−22 to −19‰) together with the increase in TOC concentration indicate elevated primary productivity in lower middle (18–22 cm) and top (0–8 cm) sections of the sediment cores. Seepage of nutrients from a nearby waste water treatment plant, rapid urbanization and heavily fertilized farming in the catchments are responsible for the increased productivity. Consistent with this, measured δ¹⁵N_organic values (∼11‰) indicate increased raw sewage input towards the top-section of the core. Although cyanobacterial blooms are evident from the low δ¹⁵N values (∼3‰) in mid-section of the core, they did not outnumber the phytoplankton population. Low N/P ratio (∼0) and high TP (100–2,200 mg l⁻¹) support cyanobacterial growth under N limited condition, and insignificant input of macrophytes towards the organic matter pool. Dredging in 1983, caused sub-aerial exposure of the suspended and surface sediments, and affected organic matter preservation in the upper mid-section (12–14 cm) of the core.