Zambra Carlos, Clausen Benjamin, Vasco Diego, Lemus-Mondaca Roberto
Department of Industrial Technologies, Faculty of Engineering, University of Talca, Curicó, Chile.
Geocience Research Institute and Loma Linda University, Loma Linda, CA 92350, USA.
Heliyon. 2023 Oct 18;9(11):e21044. doi: 10.1016/j.heliyon.2023.e21044. eCollection 2023 Nov.
This article presents an improved mathematical model and numerical simulation for weathering of large areas with complex topography. It uses the equations of momentum, temperature, and humidity in turbulent air and for heat and water infiltration into soils. A mathematical model is also presented to calculate the soil porosity fraction produced by physical rock weathering in areas where soil is produced from intrusive rocks (batholiths). An algorithm based on air velocity, humidity (rainfall), temperature variation, and soil topography was developed to quantify soil erosion and change of relief at each point and time step in air, at the ground surface, and within the soil. This results in a complete air-soil model based on conservation laws that have not previously been applied to large areas of the earth's surface. The mathematical model is solved using large-scale numerical simulations applied to an area of 6.6 km in the Sierra Nevada batholith of California, USA. The results show that the wind velocity and resulting erosion is greater in areas with steeper slopes and that moisture accumulates mainly in low and flat areas; therefore, erosion is not uniform throughout the study area. In addition, computer simulations localized calculations to discrete grid cells within the porous (saprolite) fraction of the soil produced by freezing and thawing of water in rock. Results indicate that this physical mechanism is the primary contributor to weathering of rock at the study area.
本文提出了一种改进的数学模型和数值模拟方法，用于复杂地形大面积区域的风化作用。它运用了湍流空气中动量、温度和湿度以及热量和水分渗入土壤的方程。还提出了一个数学模型，用于计算由侵入岩（岩基）形成土壤的区域中物理岩石风化产生的土壤孔隙率。开发了一种基于风速、湿度（降雨量）、温度变化和土壤地形的算法，以量化空气、地面和土壤中每个点和时间步长的土壤侵蚀和地形变化。这就形成了一个基于守恒定律的完整气-土模型，该定律此前尚未应用于地球表面的大面积区域。使用大规模数值模拟求解该数学模型，模拟区域为美国加利福尼亚州内华达山脉岩基中6.6千米的区域。结果表明，坡度较陡的区域风速和由此产生的侵蚀更大，水分主要积聚在低洼平坦区域；因此，整个研究区域的侵蚀并不均匀。此外，计算机模拟将计算定位到岩石中水分冻结和融化产生的土壤多孔（腐泥土）部分内的离散网格单元。结果表明，这种物理机制是研究区域岩石风化的主要因素。
