The South China Sea's natural gas hydrate reservoirs

primarily composed of clayey silt with non-diagenetic properties

undergo creep during depressurization development. The implications of this creep on key reservoir characteristics such as permeability

porosity

pressure

temperature

hydrate saturation distribution

and gas well productivity remain unclear. To address this

a combination of water seepage experiment data from clayey-silt cores and numerical simulation methods was employed to study the development of these hydrate reservoirs through depressurization-induced vertical wells. The simulation results show that the creep effects reduce the effective reservoir porosity and permeability while developing South China Sea natural gas hydrate reservoirs using a depressurization-induced vertical well. Specifically

the pressure drop is predominantly observed near the well

accompanied by a significant decrease in temperature around the well. Additionally

the reservoir creep results in a more pronounced pressure drop funnel within the reservoir. The hydrate decomposition mainly occurs at the regions of the near-well

the top of hydrate layer A

and the bottom of hydrate layer B

and the radius of hydrate decomposition is decreased by 66.7 % due to creep effects. The reservoir creep effects reduced the gas well productivity

and the cumulative production of the gas well in five years decreased by 87 %. The creep of the South China Sea natural gas hydrate reservoir dominates while the production pressure difference is greater than 4 MPa. As the production pressure difference is larger

the increasing degree of cumulative production gradually becomes smaller. A production pressure difference lower than 4 MPa is recommended for future long-term development. This study provides a reliable theoretical basis for developing South China Sea natural gas hydrate efficiently.