Table of Contents
- 1 What is naturally fractured reservoirs?
- 2 What is the purpose of petrophysics?
- 3 What is petrophysical analysis?
- 4 What is a natural fracture?
- 5 What is the most important source of subsurface data?
- 6 What are the petrophysical parameters?
- 7 What do you call a crack between two rocks?
- 8 Why CBM reservoir is considered as a dual porosity system?
What is naturally fractured reservoirs?
Naturally fractured reservoirs are different from conventional (unfractured) reservoirs. They are heterogeneous in type and consist of matrix blocks separated from one another by the fracture system as shown in Figure 7–1. It means a naturally fractured reservoir is a double-porosity and double-permeability reservoir.
What is the purpose of petrophysics?
Petrophysicists are employed to help reservoir engineers and geoscientists understand the rock properties of the reservoir, particularly how pores in the subsurface are interconnected, controlling the accumulation and migration of hydrocarbons.
What is a fractured reservoir?
A fractured reservoir is one in which naturally occurring fractures either have or are predicted to have a significant effect on reservoir fluid flow in the form of (1) increased reservoir permeability, (2) increased porosity, and/or (3) increased permeability anisotropy.
What is petrophysical analysis?
By their definition, petrophysics is the study of the physical and chemical properties of rocks and their contained fluids. The Society of Petrophysicists and Well Log Analysts (SPWLA) mission is to increase the awareness of petrophysics, formation evaluation and well logging best practices in the oil and gas industry.
What is a natural fracture?
1. n. [Shale Gas, Geology] A crack or surface of breakage within rock not related to foliation or cleavage in metamorphic rock along which there has been no movement. A fracture along which there has been displacement is a fault.
What is a dual porosity reservoir?
1. n. [Well Testing] A rock characterized by primary porosity from original deposition and secondary porosity from some other mechanism, and in which all flow to the well effectively occurs in one porosity system, and most of the fluid is stored in the other.
What is the most important source of subsurface data?
Drilling boreholes is the primary way used to obtain subsurface information. Drilling brings soil and rock to the surface for direct study. These materials are described on site and may also be sent to a laboratory for additional study.
What are the petrophysical parameters?
The petrophysical parameters mainly include total organic carbon (TOC) content, mineral components, porosity and hydrocarbon saturation, etc. So far, the estimation of water saturation in organic-rich shale gas and tight oil reservoirs is still a challenge.
What is a crack in a rock called?
A fracture is any separation in a geologic formation, such as a joint or a fault that divides the rock into two or more pieces. A fracture will sometimes form a deep fissure or crevice in the rock.
What do you call a crack between two rocks?
Faults are fractures in Earth’s crust where rocks on either side of the crack have slid past each other. Sometimes the cracks are tiny, as thin as hair, with barely noticeable movement between the rock layers.
Why CBM reservoir is considered as a dual porosity system?
Abstract. Coalbed methane (CBM) reservoirs are often characterized as a dual porosity system because coal is characterized by two distinct systems, namely, the matrix and the cleats. Most of the gas in a CBM reservoir is stored in the low permeability matrix, which is dominated by pores in nanometers range.