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The preliminary results are presented of observations of rapid changes in the Earth’s gravitational field recorded during short-term movements induced by longwall coal mining in the Upper Silesian Coal Basin (USCB) in Poland. Two gPhoneX tidal gravimeters were installed; one in the area of an operating mine in the southern part of the Basin and the other in the post-mining area to the north of the Basin. The foci of the tremors caused by mining were located 1-3 km from the first gravimetric station and those recorded by the second station were 6-52 km away, in the area of the distant active coal mines. Discussion is presented of the analysis of the data set of graviseismic events identified as mining tremors which were recorded by tidal gravimeters between November 2018 and June 2019 with regards to their usefulness for the study of mining induced rock mass movements. It is suggested that the ability to detect the gravity signal from mining shocks is strongly dependent on its intensity, local magnitude, and the distance to the observation station. In the USCB, the two gravimeters were able to provide the detection and recording of signals across a radius of around 50 km., The preliminary results are presented of observations of rapid changes in the Earth’s gravitational field recorded during short-term movements induced by longwall coal mining in the Upper Silesian Coal Basin (USCB) in Poland. Two gPhoneX tidal gravimeters were installed; one in the area of an operating mine in the southern part of the Basin and the other in the post-mining area to the north of the Basin. The foci of the tremors caused by mining were located 1-3 km from the first gravimetric station and those recorded by the second station were 6-52 km away, in the area of the distant active coal mines. Discussion is presented of the analysis of the data set of graviseismic events identified as mining tremors which were recorded by tidal gravimeters between November 2018 and June 2019 with regards to their usefulness for the study of mining induced rock mass movements. It is suggested that the ability to detect the gravity signal from mining shocks is strongly dependent on its intensity, local magnitude, and the distance to the observation station. In the USCB, the two gravimeters were able to provide the detection and recording of signals across a radius of around 50 km.

Regional studies indicate that the Lower Proterozoic carbonate-clastic formation, in Queensland's Mount Isa basin, was deposited under widespread shallow marine conditions. Well-developed microbial fabrics, tidal and storm facies have been recognised, while the presence of evaporite pseudomorphs and desiccation features indicate periods of brine-logging and sporadic emergence. Observations from both in and near the Lady Loretta Zn-Pb-Ag orebody confirm a broadly similar setting. There is evidence of both tidal activity and periods of quiescence under generally shallow-water conditions. The paucity of high-energy facies is consistent with deposition in a lagoon. Evidence of an evaporitic overprint suggests brine-logging of the sediments and may indicate subaerial exposure., Regional studies indicate that the Lower Proterozoic carbonate-clastic formation, in Queensland's Mount Isa basin, was deposited under widespread shallow marine conditions. Well-developed microbial fabrics, tidal and storm facies have been recognised, while the presence of evaporite pseudomorphs and desiccation features indicate periods of brine-logging and sporadic emergence. Observations from both in and near the Lady Loretta Zn-Pb-Ag orebody confirm a broadly similar setting. There is evidence of both tidal activity and periods of quiescence under generally shallow-water conditions. The paucity of high-energy facies is consistent with deposition in a lagoon. Evidence of an evaporitic overprint suggests brine-logging of the sediments and may indicate subaerial exposure.

Airborne bathymetric systems are currently under development. When fully developed, the NAVOCEANO plans to use this survey technology. NAVOCEANO faces a unique problem in using airborne bathymetry, in that it plans to survey in remote and undeveloped areas of the world where tide control obtained through tide gauge deployment is often logistically and economically prohibitive. This thesis offers a method for significantly reducing the number of tide gauges needed for tide control in such a survey when the survey is conducted in an open coast environment. The approach provides a method for delineating a tidal zone and then suggests a survey scenario which will allow the isolation of the major components of the tidal signal through a least squares adjustment. A proof of concept simulation model developed in the thesis results in tidal depth reducers which more than satisfy IHO specifications. Keywords: Global positioning system; Hydrographic surveying; Lidar; Tide control; Hydrography; Airborne lidar; Bathymetry; Least squares adjustment; Harmonic analysis. Theses.

Qianbei bauxite deposit, which is the biggest bauxite deposit in China, is a sedimentary type bauxite and is affected by sea level changes. Based on analysis of facies and geochemistry of the bauxite bearing rock series in the studied area, bauxite is known to form in shore lake and shallow lake. So, bauxite is deposited in fresh water. The hydrodynamic conditions determine type and grade of bauxite. The chlorite and bauxite rock are deposited in fan delta and tidal flat facies. The chlorite and bauxite rock are deposited during the rising of sea levels and bauxite is deposited during dropping of sea levels. The span of the drop period is much greater than that of the rise period which explains why the formation of bauxite is a long weathering process. Up to three cycles can be identified during the deposit of the bauxite bearing rock series and these three cycles are consistent with a correspondent period of carbonate rock and clastic rock deposits in the adjacent area., Qianbei bauxite deposit, which is the biggest bauxite deposit in China, is a sedimentary type bauxite and is affected by sea level changes. Based on analysis of facies and geochemistry of the bauxite bearing rock series in the studied area, bauxite is known to form in shore lake and shallow lake. So, bauxite is deposited in fresh water. The hydrodynamic conditions determine type and grade of bauxite. The chlorite and bauxite rock are deposited in fan delta and tidal flat facies. The chlorite and bauxite rock are deposited during the rising of sea levels and bauxite is deposited during dropping of sea levels. The span of the drop period is much greater than that of the rise period which explains why the formation of bauxite is a long weathering process. Up to three cycles can be identified during the deposit of the bauxite bearing rock series and these three cycles are consistent with a correspondent period of carbonate rock and clastic rock deposits in the adjacent area.

The trailing margin of the stable African continent is the depositional environment of several heavy mineral placer deposits of which seven have developed into viable world class operations producing titanium feedstock (ilmenite, rutile, leucoxene) and zircon. At least 30 other deposits are marginal under the present global economic climate but have the potential to be turned into account in the medium term with an increase in demand and higher commodity prices. Combined, the seven operating mines are the biggest single producer of titanium feedstock in the world and the second largest producer of zircon after Australia. Generally, Pliocene to Holocene unconsolidated, siliciclastic sands of predominantly marine-aeolian, but locally fluvial origin host the heavy mineral suite and deposits are large coast-parallel dune fields with or without minor strandlines. Tonnages of these deposits are large and in several instances exceed a billion tons with grades between 2 and 12% total heavy minerals (THM). Deposit characteristics are influenced by continental tectonics, coastal morphology, sea level changes, tides, climate and the altered, eroded nature and composition of the provenance. The formation of an economically viable deposit requires the juxtaposition of most, if not all of these conditions to favour heavy mineral concentration with a high VHM (valuable heavy minerals) content. Only three of the mines, all located in South Africa, have their own smelters that convert ilmenite into titanium slag and pig iron., The trailing margin of the stable African continent is the depositional environment of several heavy mineral placer deposits of which seven have developed into viable world class operations producing titanium feedstock (ilmenite, rutile, leucoxene) and zircon. At least 30 other deposits are marginal under the present global economic climate but have the potential to be turned into account in the medium term with an increase in demand and higher commodity prices. Combined, the seven operating mines are the biggest single producer of titanium feedstock in the world and the second largest producer of zircon after Australia. Generally, Pliocene to Holocene unconsolidated, siliciclastic sands of predominantly marine-aeolian, but locally fluvial origin host the heavy mineral suite and deposits are large coast-parallel dune fields with or without minor strandlines. Tonnages of these deposits are large and in several instances exceed a billion tons with grades between 2 and 12% total heavy minerals (THM). Deposit characteristics are influenced by continental tectonics, coastal morphology, sea level changes, tides, climate and the altered, eroded nature and composition of the provenance. The formation of an economically viable deposit requires the juxtaposition of most, if not all of these conditions to favour heavy mineral concentration with a high VHM (valuable heavy minerals) content. Only three of the mines, all located in South Africa, have their own smelters that convert ilmenite into titanium slag and pig iron.

Sediments from Kalpakkam were analysed to characterise heavy metal distribution. The mineral deposits are fine-grained in nature, and temporal and spatial variations are observed. Iron mineral peaks indicate that haematite is present in the samples. The abundance of iron-based minerals explains the occurrence of black grains in the beaches of Sadras and Kokillamedu. In the rest of the region, the mineral distribution is found to be poor and patchy. Uranium-based radioactive minerals, i.e. uranmicrolite, dessauite, dumontite, and sedovite, are present in the study area. The common light minerals are quartz and caminite, and the non-iron rich heavy minerals are tungusite, charoite, glagolevite, mangazeite, falkmanite, augelite, and struvite. Heavy minerals concentrated in the intertidal zone show well-developed swash marks by their typical alignment during the process of swash and backwash. Caminite is formed due to the reaction of seawater with hydrothermal fluids in a midoceanic ridge; its presence indicates the extent of onshore-offshore sediment transport. The heavy mineral distribution pattern along the Kalpakkam-Mahabalipuram stretch reveals the influence of energy conditions and fluctuations capable of transporting high-density minerals., Sediments from Kalpakkam were analysed to characterise heavy metal distribution. The mineral deposits are fine-grained in nature, and temporal and spatial variations are observed. Iron mineral peaks indicate that haematite is present in the samples. The abundance of iron-based minerals explains the occurrence of black grains in the beaches of Sadras and Kokillamedu. In the rest of the region, the mineral distribution is found to be poor and patchy. Uranium-based radioactive minerals, i.e. uranmicrolite, dessauite, dumontite, and sedovite, are present in the study area. The common light minerals are quartz and caminite, and the non-iron rich heavy minerals are tungusite, charoite, glagolevite, mangazeite, falkmanite, augelite, and struvite. Heavy minerals concentrated in the intertidal zone show well-developed swash marks by their typical alignment during the process of swash and backwash. Caminite is formed due to the reaction of seawater with hydrothermal fluids in a midoceanic ridge; its presence indicates the extent of onshore-offshore sediment transport. The heavy mineral distribution pattern along the Kalpakkam-Mahabalipuram stretch reveals the influence of energy conditions and fluctuations capable of transporting high-density minerals.

Celestite (SrSO4) mineralisation in the Lilak deposit is hosted by the early to middle Miocene Gachsaran evaporitic formation. The celestite-bearing layers are composed of medium- to coarse-grained celestite crystals with different morphologies in a carbonate groundmass. The presence of carbonate and gypsum inclusions within the crystals as well as their pseudomorphic habits suggests that celestite replaced preexisting carbonate and gypsum. The lithofacies features and faunal assemblage of the host rocks indicate subtidal-supratidal environments of deposition of country rocks. Sr-isotope analysis indicates that Sr originated from middle Miocene seawater. S-isotopic ratios indicate higher 34-S values in analysed samples than those of middle Miocene seawater. These higher values probably were the result of bacterial sulphate reduction. Based on petrographic evidence and Sr-isotope ages, it is revealed that mineralisation occurred as a late-diagenetic process during the Gachsaran Formation. Precursors of the mineralising fluids were probably produced by evaporation of seawater in a coastal sabkha setting. As these brines entered into underlying sediments, considerable amounts of Sr were leached. Sr-enriched fluids discharged back up into overlying beds containing gypsum and carbonate material, so celestite precipitation took place by replacement of preexisting minerals as well as mixing of mineralising fluids with sulphate-enriched brines entrapped within the beds., Celestite (SrSO4) mineralisation in the Lilak deposit is hosted by the early to middle Miocene Gachsaran evaporitic formation. The celestite-bearing layers are composed of medium- to coarse-grained celestite crystals with different morphologies in a carbonate groundmass. The presence of carbonate and gypsum inclusions within the crystals as well as their pseudomorphic habits suggests that celestite replaced preexisting carbonate and gypsum. The lithofacies features and faunal assemblage of the host rocks indicate subtidal-supratidal environments of deposition of country rocks. Sr-isotope analysis indicates that Sr originated from middle Miocene seawater. S-isotopic ratios indicate higher 34-S values in analysed samples than those of middle Miocene seawater. These higher values probably were the result of bacterial sulphate reduction. Based on petrographic evidence and Sr-isotope ages, it is revealed that mineralisation occurred as a late-diagenetic process during the Gachsaran Formation. Precursors of the mineralising fluids were probably produced by evaporation of seawater in a coastal sabkha setting. As these brines entered into underlying sediments, considerable amounts of Sr were leached. Sr-enriched fluids discharged back up into overlying beds containing gypsum and carbonate material, so celestite precipitation took place by replacement of preexisting minerals as well as mixing of mineralising fluids with sulphate-enriched brines entrapped within the beds.

The abandoned massive sulphide Callahan mine is unique because the open-pit operation was sited in a drained marine estuary. About 5 000 000 tons of sulphide-bearing waste and unprocessed ore remain on site, bordering ponds and tidal flats. The prominence and position of the waste relative to the tidal estuary constitute key features representing point sources of heavily contaminated debris. Pyrite, sphalerite, chalcopyrite and minor galena are hosted by bimodal volcanic rocks of the Cambrian Castine Volcanics. A total of 275 analyses of Pb isotopes were carried out to characterise fully barren volcanic, hydrothermally altered and mineralised rocks, massive and disseminated sulphides, waste rock and tailings, and pond sediments from drill cores, pit water, seeps, and aquatic biota (lobsters, crabs and bivalves). The tailings pile and Goose Pond sediments have high metal burdens. The mine signature decreases considerably in intensity away from the mine, within the estuary and towards the open waters of the Bagaduce river. Lead in the pond sediments is derived from mass wasting of Pb-bearing minerals in the waste and tailings piles and from metal-laden seeps that carry both dissolved and particulate Pb. The composition of bivalve shells and lobsters indicated that they are partially disturbed by mining activities., The abandoned massive sulphide Callahan mine is unique because the open-pit operation was sited in a drained marine estuary. About 5 000 000 tons of sulphide-bearing waste and unprocessed ore remain on site, bordering ponds and tidal flats. The prominence and position of the waste relative to the tidal estuary constitute key features representing point sources of heavily contaminated debris. Pyrite, sphalerite, chalcopyrite and minor galena are hosted by bimodal volcanic rocks of the Cambrian Castine Volcanics. A total of 275 analyses of Pb isotopes were carried out to characterise fully barren volcanic, hydrothermally altered and mineralised rocks, massive and disseminated sulphides, waste rock and tailings, and pond sediments from drill cores, pit water, seeps, and aquatic biota (lobsters, crabs and bivalves). The tailings pile and Goose Pond sediments have high metal burdens. The mine signature decreases considerably in intensity away from the mine, within the estuary and towards the open waters of the Bagaduce river. Lead in the pond sediments is derived from mass wasting of Pb-bearing minerals in the waste and tailings piles and from metal-laden seeps that carry both dissolved and particulate Pb. The composition of bivalve shells and lobsters indicated that they are partially disturbed by mining activities.

Ten types of mining methods are identified, of which seven are suitable for deep-seated deposits and four for shallow deposits. Cutter suction dredges are applicable to both types of deposit. Method selection is based on many factors: deposit type, type of material to be dredged, desired rate of production, location, materials and tailings handling, equipment availability and environmental concern. Profitability is the most important factor. From the data given, the most suitable method for mining deep-seated tin deposits is by bucket line dredges while cutter suction dredges are most suitable for shallow deposits. To achieve optimum working conditions and mining recovery it is important to maintain the paddock water by building a dam in an appropriate area, implementing dry overburden stripping if possible, and pumping the slime out of the paddock if the turbidity is too high., Ten types of mining methods are identified, of which seven are suitable for deep-seated deposits and four for shallow deposits. Cutter suction dredges are applicable to both types of deposit. Method selection is based on many factors: deposit type, type of material to be dredged, desired rate of production, location, materials and tailings handling, equipment availability and environmental concern. Profitability is the most important factor. From the data given, the most suitable method for mining deep-seated tin deposits is by bucket line dredges while cutter suction dredges are most suitable for shallow deposits. To achieve optimum working conditions and mining recovery it is important to maintain the paddock water by building a dam in an appropriate area, implementing dry overburden stripping if possible, and pumping the slime out of the paddock if the turbidity is too high.