# Dynamic Prediction of Shale Gas Drilling Costs Based on Machine Learning
## 3 Materials and Methods  
### Shale Gas Cost Structure Explained  
As an unconventional natural gas resource, the development and production of shale gas is not only of great importance to the energy industry, but also has a significant impact on economic, environmental and social development. To fully understand the cost structure of shale gas, several factors need to be carefully considered, including exploration and development, production and transportation costs.  
First, exploration and development costs are the primary expenditure in shale gas projects. These costs include geological exploration, drilling, reservoir evaluation, engineering design and equipment procurement. Shale gas resources are typically located in deep formations, and the exploration and development process requires significant capital and human resources to determine the presence of natural gas and estimate recoverable reserves [35]. In addition, the complexity of shale gas reservoirs requires the use of advanced technology and equipment for development, which further increases exploration and development costs.  
Second, production costs are a critical factor affecting the economic viability of shale gas development. In the shale gas development process, production costs mainly include well operating costs, hydraulic fracturing operations and capacity maintenance [36]. Compared to conventional natural gas production, shale gas production requires extensive hydraulic fracturing to release the natural gas, which significantly increases production costs. In addition, the extended production cycle of shale gas requires continuous investment in maintaining production capacity and implementing post-production management, further increasing production costs.  
In addition, transportation costs are a significant component of the shale gas cost structure. Shale gas development often takes place in remote areas or regions with complex geological conditions, and the transportation, processing and storage of natural gas requires significant resources and capital investment. In particular, the construction, operation and maintenance costs of transport pipelines have a direct impact on the overall economics of shale gas development [37].  
Beyond the primary factors mentioned above, the cost structure of shale gas is influenced by several additional elements, including technological progress and innovation, regulatory policy, capital market conditions and geological characteristics. Technological progress and innovation can reduce exploration and development costs while improving production efficiency, thereby reducing overall costs. Changes in policy and regulation have a direct impact on the cost of shale gas projects through fiscal policy, environmental standards and exploration and production licences. Capital market conditions and the investment environment affect the cost of financing and investment decisions for shale gas projects. In addition, regional geological conditions influence the complexity of shale gas exploration and development, which in turn affects the cost structure [38].  
Therefore, elucidating the cost structure of shale gas requires consideration of multiple aspects, including exploration and development, production and transportation costs, as well as the influence of technological, political, capital and geological factors. Understanding these elements is crucial for formulating appropriate development strategies, optimising production costs and enhancing competitiveness [39].