Dataset of Israeli et al 2020-Impact of textural patterns on rock weathering rates and size distribution of weathered grains

These data files here were used to generate the figures and results in the manuscript by Israeli, Salhov, and Emmanuel entitled "Impact of textural patterns on rock weathering rates and size distribution of weathered grains”. This paper describes the use of a numerical model that simulates chemical weathering and grain detachment in rocks with different textural patterns. We use a cellular automaton model to simulate the weathering of rocks possessing grain boundaries, cracks, and stylolites. We ran simulations of both synthetic patterns as well as natural patterns of cracks, and stylolites. A 2-D cross-section of the rock was represented using a domain with 560*420 elements. Each element represented either a solid mineral, a discontinuity, or a fluid phase and is assigned a characteristic value. At each step, we calculated the number of elements removed by chemical weathering and by mechanical weathering. The dimensions and locations of each detached grain were recorded. The available reactive surface in every time step was also calculated, based on the location of the pixels that neighbor the reactive fluid. The data were then analyzed to assess the weathering rate and the grain size distribution of the detached fragments. When calculating the grain size distributions, we only considered detached clusters larger than 10 pixels, and the amplitude of each size bin represents the cumulative number of pixels of the individual grains within the bin. The data from every simulation included the rock’s initial properties and the dynamic properties of the rock in every step. These properties include the matrix of the rock in every step, a list of pixels that were dissolved, location, and dimensions of detached fragments in every step. The data was uploaded into a MySQL database facilitating analysis of the datasets. We found that for all patterns, weathering rates increase with the density of discontinuities. When the abundance of discontinuities was lower than ~25%, the synthetic patterns weathering rate followed the order: grid> honeycomb> Voronoi> brick-wall. However, for higher values of discontinuity density, all patterns exhibit similar weathering rates. We also tested the impact of the tortuosity of the pattern on weathering rates, and found rates to decrease with increasing tortuosity. In addition, we show that the rock textural pattern strongly impacts the detached grain size distributions. Rocks with an initial monomodal grain size distribution produce weathered fragments that are normally distributed. In contrast, rocks with an initial log-normal size distribution produce weathered grains that are log-normally distributed. For the natural rock patterns, weathering changed the initial multimodal grain size distributions to lower modality distributions. We show how discontinuities, such as cracks, grain boundaries, and stylolites impact rock weathering rates and the size distribution of weathered grains.

本数据集配套文件用于生成Israeli、Salhov与Emmanuel联名发表的题为《纹理模式对岩石风化速率及风化颗粒粒径分布的影响》（"Impact of textural patterns on rock weathering rates and size distribution of weathered grains"）的手稿中的图表与研究结果。该研究阐述了一款数值模型的应用，该模型可模拟具有不同纹理模式的岩石的化学风化过程与颗粒剥离过程。本研究采用元胞自动机（Cellular Automaton）模型，模拟带有晶界、裂缝与缝合线（stylolites）的岩石的风化过程。我们分别开展了人工合成裂缝与缝合线模式，以及天然裂缝与缝合线模式的模拟实验。岩石的二维剖面由包含560×420个单元的域表示。每个单元可代表固态矿物、不连续面或流体相，并被赋予特征值。每一步模拟中，我们都会计算经化学风化与机械风化剥离的单元数量，并记录每个剥离颗粒的尺寸与位置。此外，我们还会根据与反应流体相邻的像素位置，计算每个时间步内的有效反应表面积。随后对数据集进行分析，以评估风化速率与剥离碎屑的粒径分布。计算粒径分布时，我们仅考虑尺寸大于10像素的剥离团簇，每个粒径区间的幅值代表该区间内单个颗粒的像素累计数量。每一次模拟得到的数据均包含岩石的初始属性，以及每一步模拟中岩石的动态属性。这些属性包括每一步的岩石基质、已溶解像素列表，以及每一步中剥离碎屑的位置与尺寸。本数据集已上传至MySQL数据库，以方便后续分析。研究发现，对于所有纹理模式，风化速率均随不连续面密度的升高而提升。当不连续面占比低于约25%时，人工合成模式的风化速率排序为：网格状>蜂窝状>沃罗诺伊（Voronoi）状>砖块状。而当不连续面密度更高时，所有模式的风化速率均趋于相近。我们还测试了纹理模式的曲折度对风化速率的影响，发现风化速率随曲折度升高而降低。此外，研究表明岩石纹理模式对剥离颗粒的粒径分布具有显著影响。初始粒径分布为单峰型的岩石，其风化碎屑的粒径分布呈正态分布；与之相对，初始粒径分布为对数正态型的岩石，其风化颗粒的粒径分布呈对数正态分布。对于天然岩石纹理模式，风化作用会将初始多峰型粒径分布转变为峰数更少的分布。本研究阐明了裂缝、晶界与缝合线等不连续面如何影响岩石风化速率及风化颗粒的粒径分布。

搜集汇总

背景与挑战

背景概述

该数据集基于以色列等人2020年的研究，通过数值模型模拟了岩石在不同纹理模式（如晶界、裂缝和缝合线）下的化学风化和颗粒脱落过程。数据包括岩石的初始和动态属性，存储在MySQL数据库中，用于分析风化速率和脱落颗粒的尺寸分布。研究发现，风化速率随不连续性密度增加而上升，且纹理模式显著影响颗粒尺寸分布，例如单峰分布岩石产生正态分布碎片，而自然模式则降低多峰性。