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The Impact of Coal Exploitation on Tidal Flat Changes, an Investigation Using Remote Sensing Data in Vietnam

Pham Thi Lan, Tong Si Son, Le Thi Thu Ha, Le Thi Le, Hoang Huu Duc

Inżynieria Mineralna

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2021

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no. 2

521--532

EN

Tidal flat plays a crucial role in socio-economic development and ecological environment. Tidal flats in Ha Long-Cam Pha in Vietnam are impacted by human activities, especially coal mining activities. Using remote sensing data is able to detect, extract, and monitor the changes of tidal flats and exploited coal mine area with multi-temporal, in various scales, and for a large coverage. This study aims to investigate the impact of coal mining activities on the changes of tidal flats using remote sensing in Cam Pha, Ha Long, one of the biggest coal basins in Vietnam. Digital Elevation Models (DEMs) of tidal flats constructed by Landsat satellite images acquired in years 1989, 2001, and 2014 are compared to determine the volume changes. Besides, coal mining activities including coal production, waste rock dump area, and the expansion of open coal mine during the period 1989-2014 are investigated using correspondent Landsat images and the reports from the coal mine companies in the study area. Sediment samples in tidal flats are analyzed to determine the origin of the sediments. As the results, organic matter in the tidal flats is dominant with the concentration of 459 g/kg to 607 g/kg, which is evidence for the impact of coal exploitation on the coastal environment. In addition, the relationship between coal mine activities and tidal flat variation is well observed in this study.

2

Colonies of Gyrosigma eximium: a new phenomenon in Arctic tidal flats

Wiktor J., Tatarek A., Węsławski J. M., Kotwicki L., Poulin M.

Oceanologia

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2016

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No. 58 (4)

336--340

EN

For the first time at Svalbard, a colonial form of the tube-dwelling diatom Gyrosigma eximium was found in summer 2010 in the tidal flats on Spitsbergen at 78°N. The colonies take the form of conical, green structures that are 1–2 cm high and are associated with other diatom taxa and cyanobacteria (Oscillatoriaceae). The diatom colonies were associated with rich meiofauna and apparently act as cohesive factors for the fine sediment. In the Arctic tidal flats, this represents the first observation of long-term sediment stabilization and biological enrichment. Since this first observation, this species has apparently colonized broader areas in Advenentelva's tidal flat.

3

Pterosaur tracks from the early Kimmeridgian intertidal deposits of Wierzbica, Poland

Pieńkowski G., Niedźwiedzki G.

Geological Quarterly

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2005

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Vol. 49, No. 3

339--346

EN

In the early Kimmeridgian (hypselocyclum Zone) tidal flat carbonate deposits cropping out in the large Wierzbica quarry at northern slope of the Holy Cross Mountains (20 km south of the town of Radom), characteristic Pteraichnus sp. tracks have been found. These tracks are assigned to pterosaurs and represent the first pterosaur ichnites found in Poland. Seven specimens of pterosaur tracks (pes and manus prints) are described, although no trackway can be observed. The manual prints are asymmetric, digitigrade and tridactyl. The pedal prints are elongate, symmetrical, plantigrade and functional-tetradactyl. Presence of pterosaur tracks point to subaerial conditions and supports the view that the Late Jurassic land, situated in Ukraine and Eastern Poland, temporarily extended to the northern part of the Holy Cross Mountains area.

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Oolitowy cykl sedymentacyjny wczesnego kimerydu w profilu Wierzbicy koło Radomia

Gutowski P.

Volumina Jurassica

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2004

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Vol. 2, no. 1

37-48

EN

The Lower Kimmeridgian (Hypselocyclum Zone) section, exposed, in the lower part of the abandoned cement works quarry in Wierzbica, NE margin of the Holy Cross Mountains, Central Poland, represents a shallowing upward sedimentary cycle deposited on a carbonate ramp that developed in the SW margin of the East European Platform. Succession of the sedimentary environments has been recognized according to the variety of typical sedimentary structures as follows: open shelf (outer ramp), oolitic barrier, protected bay, hypersalinary lagoon and tidal flat. This sedimentary cycle resulted from relative sea level rise and corresponding encroaching of the sea onto inner carbonate ramp which was followed by stillstand (or slow fall) of the sea level and connected basinward progradation of the oolitic shoals. Rhizoids and aggregations of cycadacean trunks on beach bars found in the uppermost part of the cyclothem indicate emersion of the area studied. Hardground and erosional structures developed in the top of the cyclothem during a later highstand of sea level.