Enrichment Mechanism and Prospects of Deep Oil and Gas

Abstract

With the deepening of oil and gas exploration, the importance of depth is increasingly highlighted. The risk of preservation of storage space in deep reservoirs is greater than that in shallow and medium layers. Deep layers mean older strata, more complex structural evolution and more complex hydrocarbon accumulation processes, and even adjustment and transformation of oil and gas reservoirs. This paper systematically investigates the current status and research progress of deep oil and gas exploration around the world and looks forward to the future research focus of deep oil and gas. In the deep, especially the ultra-deep layers, carbonate reservoirs play a more important role than clastic rocks. Karst, fault•karst and dolomite reservoirs are the main types of deep and ultra-deep reservoirs. The common feature of most deep large and medium-sized oil and gas reservoirs is that they formed in the early with shallow depth. Fault activity and evolution of trap highs are the main ways to cause physical adjustment of oil and gas reservoirs. Crude oil cracking and thermochemical sulfate reduction (TSR) are the main chemical modification effects in the reservoir. Large-scale high-quality dolomite reservoirs is the main direction of deep oil and gas exploration. Accurate identification of oil and gas charging, adjustment and reformation processes is the key to understanding deep oil and gas distribution. High-precision detection technology and high-precision dating technology are an important guarantee for deep oil and gas research.

Hydrocarbon Phase State Evolution and Accumulation Process of Ultradeep Permian Reservoirs in Shawan Sag, Junggar Basin, NW China

“…The type of hydrocarbon phase in the reservoir not only affects resource evaluation, field development, and facilities design but also has different economic benefits. ,, In addition, there are differences in the physical properties (e.g., density, viscosity, interfacial tension) of hydrocarbons with different phase states, resulting in significant differences in the dynamics of hydrocarbon charging, migration, and accumulation. − It is of great importance for understanding the current compositional distributions in the reservoir, the mechanism of the migration and accumulation of hydrocarbons in ultradeep reservoirs, and explaining the distribution of hydrocarbons in different phase states in a basin. − …”

A Supramolecular Reinforced Gel Fracturing Fluid with Low Permeability Damage Applied in Deep Reservoir Hydraulic Fracturing

“…The development of conventional oil and gas reservoirs has gradually entered the middle or late period [1][2][3][4]. How to efficiently develop deep reservoirs with abundant reserves attracts the interest of researchers [5][6][7]. The buried depth of the deep reservoir determines that most of its permeability is low, and the process of oil or gas gathering to the bottom of the well will be subject to great flow resistance [8,9].…”

Comprehensive Study of Development Strategies for High-Pressure, Low-Permeability Reservoirs

“…In China, there are numerous low-permeability oil reservoirs, and their flow characteristics are mainly non-Darcy flow. Abnormally high-pressure low-permeability reservoirs, as a specific type of low-permeability reservoir, are mainly distributed in regions such as Xinjiang, Bohai Sea, South China Sea, and Sichuan [1][2][3][4]. These reservoirs typically share the following characteristics: deep deposition, high original reservoir pressure, strong heterogeneity, complex geological structures, and rock pore structures, making oil-water flow challenging.…”