# Construction of a Geological Fault Corpus and Named Entity Recognition
## 2 Related Work
### Analysis of Textual Characteristics of Fault Investigation Report  
A geological report is a crucial technical document which comprehensively reflects the results of geological survey work. It is compiled based on historical data from the study area as well as current survey results. A typical geological report consists of the main text along with various diagrams, tables, annexes and other Supplementary Materials. Based on the type of geological work, these reports can be categorized into mineral geological reports, hydrogeological reports, petroleum geological reports, regional geological reports and so on. While the specific content of these reports may vary, they all adhere to a standardized text structure, and the final report must be evaluated by the relevant authorities. An in-depth understanding of the textual characteristics of geological reports is a prerequisite for the development of a complete corpus. A fault investigation report is a specific type of geological report focused on the active faults in a given area. Its purpose is to identify the distribution characteristics of these faults, assess the activity of typical faults, determine earthquake distribution patterns, and analyze geological hazards. This information is used to evaluate regional crustal stability, propose danger management and control measures for active faults, and ensure the safety of major infrastructure projects. As the most authoritative and detailed geological data, fault investigation reports are characterized by extensive textual content and abundant illustrations. Therefore, extracting and analyzing the textual data are crucial for summarizing geological work, understanding geological evolution, and promoting digital geological scientific research in the study area. Analysis of the fault investigation report reveals although the structure of these reports may vary by region, the content generally adheres to relevant industry standards. The report is divided into two main parts: the geological background of the study area and the characteristics of active faults in that area. The geological background section includes information on the geographical location, topography, geomorphological features, geological structure, stratigraphic lithology, and other relevant data. The section on active faults details the spatial distribution, structural characteristics, fault activity, and fault structure. These elements serve as essential knowledge carriers in the fault investigation report, and the efficient and accurate recognition of these features is fundamental to knowledge extraction from the report. Through the analysis of the language description of the fault investigation report, it is found that the fault investigation report firstly records the specific name of the fault and its location information, which is usually expressed by the regional geographic name or latitude and longitude, and its essence is the expression of the semantic relationship to the geographic location of the fault; secondly, it records the information of the fault production status, scale, and the stratigraphy of the fault outcrops, which is the expression of the semantic relationship to the fault attributes; and the fault activity always forms or leaves a lot of tectonic phenomena. Fault activities always form or leave many tectonic phenomena; for example, tectonic lenses, fault rocks, and other tectonic features related to faults and the record of fault tectonic components, the core of which is the expression of the attributes and the relations of fault tectonics as the core element; the age and rate of activity are used to characterize the activity of faults, which is the expression of the attributes and relations of faults based on the activity of faults as the core element; the presence of faults usually affects ridges and water resources, and the existence of faults is often the cause of the impact of the faults on the environment.