Coastal erosion is a worldwide problem, so accurate knowledge of the factors involved in the shoreline evolution is of great importance. This study analysed three gravel beaches that were nourished with sand from the same source. However, the evolution of their shoreline was different in each case. For its analysis, different factors were studied such as the shoreline and cross-shore profile evolution, the maritime climate, sedimentology and mineralogy. From the results, it should be noted that Centro beach is the most stable with a loss of surface after the first regeneration of 12.8%, while Carrer de mar is the most instable with a loss of 20.9%. The Posidonia oceanica meadow is one of the factors that make Centro beach the most stable despite being the one that receives the most wave energy. Another factor is its mineralogy and more specifically the composition of the particles that form the sample. Thus, it is observed how the cracking or the formation of particles by different minerals with a fragile union, are factors that make the beaches behave differently against erosion. For this reason, it is concluded that in order for the shoreline to be as stable as possible over time, a previous study of the sediment to be used for nourishment is necessary, as well as its possible effect on the ecosystem, since the future shoreline evolution will depend on it.

海岸侵蚀是一个世界性的问题，因此准确了解海岸线演变所涉及的因素非常重要。这项研究分析了三个砾石海滩，这些海滩都用同一来源的沙子滋养。但是，每种情况下其海岸线的演变都不同。为了进行分析，研究了不同的因素，例如海岸线和跨岸剖面的演变，海洋气候，沉积学和矿物学。从结果中可以看出，Centro海滩最稳定，第一次再生后损失了12.8％，而Carrer de mar最不稳定，损失了20.9％。该Posidonia大洋洲草甸是使Centro海滩最稳定的因素之一，尽管它是接收最多波浪能的海滩。另一个因素是其矿物学，更具体地说是形成样品的颗粒的组成。因此，观察到由不同矿物以易碎的结合物产生的开裂或颗粒形成是如何使海滩在侵蚀方面表现出不同的因素。因此，得出结论，为了使海岸线随着时间的推移尽可能稳定，有必要对用于营养的沉积物进行先前的研究，以及其对生态系统的可能影响，因为未来的海岸线进化将取决于它。