DST stands for Drill Stem Test, a crucial well testing technique used in the oil and gas industry to assess the potential of a newly drilled well. It involves isolating a specific zone within the wellbore and conducting a controlled production test to gather valuable data about the reservoir.
Here's a breakdown of the process:
Benefits of DST:
Types of DST:
DST: An essential tool in reservoir evaluation
The DST plays a vital role in the success of oil and gas exploration and development. It provides essential information about the reservoir and its potential, informing crucial decisions regarding well completion, production planning, and ultimately, project profitability. This valuable tool allows oil and gas companies to optimize their operations and maximize their returns from the reservoir.
Instructions: Choose the best answer for each question.
1. What does DST stand for?
(a) Drill Stem Test (b) Deep Sea Test (c) Downhole Sampling Tool (d) Dynamic Stability Test
(a) Drill Stem Test
2. What is the primary purpose of a packer during a DST?
(a) To clean the wellbore (b) To measure fluid flow rate (c) To isolate the targeted zone (d) To stimulate the reservoir
(c) To isolate the targeted zone
3. Which of the following is NOT a benefit of conducting a DST?
(a) Assessing reservoir pressure (b) Estimating production potential (c) Determining wellbore diameter (d) Characterizing fluid properties
(c) Determining wellbore diameter
4. What type of DST is conducted using a smaller tool and minimal surface equipment?
(a) Conventional DST (b) Repeat Formation Tester (RFT) (c) Wireline Formation Tester (WFT) (d) Production Test
(b) Repeat Formation Tester (RFT)
5. Why is DST considered a crucial tool in the oil and gas industry?
(a) It allows for early detection of gas leaks. (b) It helps in determining the profitability of a well. (c) It measures the temperature of the reservoir. (d) It is used to extract samples of the reservoir rock.
(b) It helps in determining the profitability of a well.
Scenario: A DST was conducted on a newly drilled well. The following data was collected:
Task:
1. **Potential of the Reservoir:** The reservoir has a high initial pressure (2,500 psi), indicating a potentially productive formation. The flow rate of 1,000 BOPD suggests a significant production capacity. 2. **Fluid Composition:** The high oil content (90%) is favorable for production. The presence of gas and water indicates that the reservoir may be a mixed-phase reservoir, requiring proper processing techniques to separate the fluids. 3. **Well Completion and Production Planning:** This data can be used to: * **Choose the appropriate well completion method:** For example, a well completion strategy may be chosen to maximize oil production while managing gas and water production. * **Design production equipment:** The flow rate and fluid composition will inform the design of surface equipment, such as separators and pipelines. * **Plan for reservoir management:** Understanding the reservoir pressure and fluid properties is crucial for optimizing production over the long term.