Field and petrographic descriptions of recent sabkha sediments at the eastern coast of Al-Kharrar lagoon, Red Sea coast of Saudi Arabia indicate the co-existence of gravel-sized, arrowhead, twinned gypsum crystals (< 23 cm long) and lenticular gypsum crystals (4–10 cm in size) of subaqueous and subaerial origin, respectively. Sand- and silt-sized, individual, lenticular and tabular gypsum crystals are widespread in the subsurface sediments of the sabkha. The twinned and lenticular gypsum crystals are highly enriched in sediment impurities, whereas tabular gypsum consists of clear crystals that are commonly associated with microbial lamination. The arrowhead, twinned gypsum crystals are formed subaqueously in a permanent supratidal pond that subsequently desiccated into a supratidal sabkha due to artificial construction of a barrier of concrete wall and gravelly dumps at the eastern margin of the lagoon. The lenticular and tabular gypsum crystals grow subaerially below the sediment surface of intertidal–supratidal sabkha by inclusive and displacive growth. The hindered supply of tidal floods to the former supratidal pond due to barrier construction leads to change in the depositional condition from upward, free growth of twinned gypsum crystals on the floor of the supratidal pond, to intrasediment growth of lenticular and tabular gypsum in a subaerial, supratidal sabkha setting. Deflation of fine sediments from the desiccated pond leads to exposure of a mixture of gravel-sized, arrowhead, twinned and lenticular gypsum crystals on the surface of the present day, supratidal sabkha setting. The results of this study indicate that the rapid change in the depositional condition due to human inference leads to desiccation of the supratidal pond, and changes in the morphology of the deposited gypsum from arrowhead, twinned crystals to lenticular crystals.

沙特阿拉伯红海海岸Al-Kharrar泻湖东海岸最近的萨布卡沉积物的田野和岩相描述表明，砾石大小，箭头，孪晶石膏晶体（<23 cm长）和透镜状石膏晶体（起源于水下和地下的大小分别为4-10厘米。sabkha的地下沉积物中广泛分布着沙粒和粉粒大小，单个，透镜状和板状的石膏晶体。孪晶和透镜状的石膏晶体富含沉积物杂质，而平板状石膏则由通常与微生物层压相关的透明晶体组成。箭头，孪生石膏晶体在水下永久性池塘中水下形成，随后由于在泻湖东缘人工建造的混凝土墙和砾石堆筑物的屏障而被干燥成上部的sabkha。柱状和片状石膏晶体通过包容性和位移性生长在潮间带至上up的沉积物表面以下的亚空中生长。由于屏障的建设，潮汐洪水向前上鳍池塘的供应受阻，导致沉积条件发生变化，从上层池塘底部孪生石膏晶体的自由生长向上生长到空中亚片状和板状石膏的沉积内增长。 ，rat上sabkha设置。干燥池中细小沉积物的放气导致砾石大小，箭头，在当今的表面上，翼上sabkha设置中，双晶和双凸透镜状的石膏晶体。这项研究的结果表明，由于人为推论，沉积条件的快速变化导致了上方池塘的干燥，沉积石膏的形态也从箭头，孪晶和双凸透镜转变为结晶。