Deep Gold Exploration with SQUID TEM in the Qingchengzi Orefield, Eastern Liaoning, Northeast China

The Qingchengzi orefield is an important polymetallic ore concentration zone in the northern margin of the North China Craton (NCC). The region has significant metallogenic potential for deep mining. Many areas with gold mineralization have been found in the shallow area of Taoyuan–Xiaotongjiapuzi–Linjiasandaogou in the east of the Qingchengzi orefield. To assess the distribution of mineralization levels, we carried out deep exploration using the transient electromagnetic method (TEM). A superconductive quantum interference device (SQUID) magnetometer and a conventional induction coil were used for field data acquisition. The SQUID data inversion results reflect the bottom interface of the high-conductivity area, the fold state of the underlying dolomite marble stratum, and the deep structural characteristics of the syncline. Secondary crumples appear in the inversion results of the southern segment of TEM, which is inferred as a favorable area for deep gold mineralization. Negative values appear in the SQUID data of some stations, to varying degrees. This induced polarization phenomenon may be related to deep gold mineralization.

CONSERVATION AND MAINTENANCE CONCEPTS OF SOONG CHING LING’S DOLOMITE MARBLE STATUE IN SHANGHAI AND SUPPORTING SURVEY METHODS

The dolomite marble statue of Madam Soong Ching Ling, Honorary Chairlady of the People’s Republic of China, is situated in the memorial square of Soong Ching Ling’s Mausoleum in Shanghai, China. The statue is composed of 4 pieces of white marble (Hanbaiyu) from Fangshan, Beijing. The statue, along with the mausoleum, has been listed as a national monument since 1982, yet severe deterioration occurred in recent years. In May 2018, a diagnostic investigation of the statue was carried out. Aided by advanced photogrammetry methods such as 3D modelling, macro photography and infrared thermography, all micro cracks were identified and labelled. Other advanced in-situ and laboratory surveys such as in-situ microscope, ultrasonic CT inspection, chalking evaluation test and mineralogical investigation were applied to further evaluate the condition. Based on analysis of all test results, conservation and maintenance concepts including a monitoring program specifically to control cracking has been developed. This concept was approved by the authorities and implemented in May 2019. After two years’ exposure, an evaluation of previous conservation and a new maintenance work were recently completed in April 2021. A long-term monitoring strategy as well as maintenance methods will be worked out based on the evaluation of all implemented efforts and climatic data.

New Metakaolin-Based Geopolymers with the Addition of Different Types of Waste Stone Powder

The search for new alternative raw materials and their subsequent use supports the sustainability of natural resources. This article describes the use of waste stone powder (WSP) in geopolymer synthesis. Five different types of WSP (feldspar, limestone, marlstone, dolomite, marble) were comprehensively characterized and their influence on the resulting properties (especially mechanical and textural properties, setting time and structure) of metakaolin-based geopolymer composites was investigated. Their comparison with a geopolymer composite containing only quartz sand has revealed that WSP additions have a small but positive effect on the mechanical or textural properties of geopolymers. Moreover, setting time measurements have shown that waste stone powders can be used as an accelerator of geopolymer reaction solidification. The results demonstrated that the mentioned types of WSP, previously landfilled, can be used for the preparation of geopolymers. This can help reduce the environmental burden.

Sorptivity and Durability Assessment of Dolomite Impregnated Ternary Concrete

Traditional testing methods such as absorption test and permeability test are normally not providing accurate results of nature of concrete and there is a need for another type of test to predict the durability of concrete. In this work, industrial by-product like dolomite, marble dust and fly ash are utilized as fraction of cement replacing with 2%, 4%, 6%, 8%, and 10% dolomite, 10% fly ash and 10% marble dust by the weight of cement. The study is conducted on mix designed concrete of M30 grade and compared with conventional concrete. The specimens are casted and tested to examine various properties of concrete like compressive strength, split tensile strength, durability and sorptivity. Durability test is done by hydrochloric acid (HCl) and sulphuric acid (H2SO4 ) on dolomite powder, promising results were obtained in the sorptivity test which shows the dense nature of concrete by the usage of dolomite powder.

Experimental Determination of Mechanical Characteristics of Four Types of Stones and their Influence on the Construction Machinery Parts Wear

In this paper were experimentally determined properties of four different types of stones and stone aggregates and they were compared to each other with respect to their influence on wear of working parts of machines for preparation and deposition of stones on roads. Rocks, the building stones are obtained from, consist of various types of minerals, namely of physically and chemically homogeneous rocks created within the Earths crust. Here are considered four, most important types of building stones: limestone, dolomite marble, calcite-dolomite marble and andesite. They are being exploited from four sites in Serbia, and they are convenient for deposition of certain layers of the carriageway on roads, streets, airports and foundations on railways, as well as for making different kinds of concrete and asphalt. In the paper are presented results of mineralogical-petrographic, physical-mechanical and special investigations. Wear resistance was also checked on certain samples.