Current Industry Practices
There are methods used to locate reservoirs and methods of evaluations to assess if reservoirs and their content are worth exploration.
Involved in the process are petroleum and reserve engineers, regulatory compliance specialists with the Rail Road Commission of Texas and geologists.
Petroleum engineering is focused on the activities related to the production of hydrocarbons, which can be either crude oil or natural gas. The upstream sector of the oil and gas industry is commonly known as exploration and production. Exploration by geologists and petroleum engineers are the oil and gas industry's two main subsurface disciplines, which focus on economic recovery of hydrocarbons from subsurface reservoirs.
Petroleum geologists and geophysics focus on provision of a static description of the hydrocarbon reservoir rock, while petroleum engineering focuses on estimation of the recoverable volume of this resource using a detailed understanding of the physical behavior of oil, water and gas within porous rock at various degrees of pressure.
To Drill in Texas the approval of the Texas Rail Road Commission (RRC) is mandatory. A compliance officer or regulatory compliance specialist is a consultant whose responsibilities include ensuring that the developer complies with the RRC regulatory requirements and internal policies. An RRC compliance officer may review and set standards for outside communications by requiring disclaimers in emails, or may examine facilities to ensure that they are accessible and safe. Compliance officers may also design or update internal policies of the developer to mitigate the risk of the company contravening laws and regulations, as well as lead internal audits of procedures.
Seismology data is used to evaluate the underground formations in order to understand substructure where oil may be trapped. The data is acquired by sending sound waves into the ground and measuring the return of the waves on recorders at the surface. This is an extremely expensive method and not useful when working in shallow fields such as Schenkel and Massie West.
Coring is a process where a small amount of rock sample is taken out of the ground from a drilling rig. When the zone of interest to be evaluated is identified, the core bit is used with the core barrel to retrieve the sample to be sent to a lab for analysis. Porosity, permeability and mobility are reliable ways to measure the productive characteristics of the formation.
Electric logs are used to evaluate rock type, porosity of the formation, presence of oil, water and gas and many other elements. After a hole is drilled, the logger will lower tools down the hole to read certain rock characteristics. Logs are reliable, but a core sample gives better quality data. The benefit of logs is that they are far less expensive than coring and are more economically viable to run on every well. Geologists and engineers interpret the data and determine the viability of establishing oil production. Maps are constructed from the data and new wells are drilled and completed based on the specific data acquired in the logs.
The primary recovery stage relies on underground pressure to drive oil to the surface. When the pressure falls, artificial lift technologies, such as pump jacks or electric submersible pumps, are used to help bring more fluids to the surface.
In some situations, natural gas at the top of the reservoir is pumped back down the well underneath the oil. The gas expands, pushing the oil to the surface. Primary recovery often taps only 10 percent of the oil in a deposit. When the primary recovery is exhausted secondary recovery is initiated.
When the underground pressure in the well fails and is insufficient to force the oil to the surface water flooding is most commonly used. Water that is produced and separated from the oil in the initial phase of drilling, or water available from water wells, is injected to increase reservoir pressure. In addition to boosting oil recovery, water flooding also disposes of the waste water and in the process, recovers 20 to 50 percent of the oil in place as a function of reservoir quality, sometimes with the use of surfactants and polymers.
Enhanced oil recovery (Tertiary Recovery) techniques are used to mobilize the remaining oil in order to increase extraction. There are three major approaches: thermal recovery (steam flooding and fire flooding), gas injection and chemical flooding. It also sometimes involves the use of surfactant. Surfactant EOR (enhanced oil recovery) is one of the more promising types of technologies for the recovery of stranded oil. Surfactants are broad groups of mostly nontoxic “soaps” or chemicals which come in both industrial-strength powder and liquid. Surfactants reduce the viscosity of the oil in the reservoir and make the oil easier to recover.
In thermal recovery steam is injected into the formation. The heat from the steam makes the oil flow more easily by reducing its viscosity, and the increased pressure forces it to the surface.
In a steam flood, sometimes known as a steam drive, steam is pumped into the well. Two mechanisms are at work to improve the amount of oil recovered. The
first is to heat the oil to higher temperatures and to thereby decrease its viscosity so that it more easily flows through the formation toward the
producing wells. A second mechanism is the physical displacement of oil by creating pressure in the reservoir and pushing the oil to the producing
In-situ combustion, sometimes known as fire flooding, is another thermal recovery method. It involves continuously injecting air into the well and heating the formation with a down-hole heater until spontaneous combustion of the oil occurs and it starts burning. The burn front advances and pushes the oil to the producing wells. Fire flooding typically produces more oil in place than the other methods because of the change in oil viscosity and pressure; however, it is the most expensive of the common techniques.
GTN Energy Partners Technologies
The energy return from the surface rocks in west Texas makes it difficult to acquire quality data. Although seismic surveys have been purchased using older data, the shallow depth of the reservoirs' oil make the information almost useless.
We focused on the expertise of our geologist, engineer and regulatory compliant specialist to interpret the data including successes and failures, from surrounding fields as well as that of the Massie West Ranch field. We used this information, along with a technology called the Microbial Oil Survey Technique (MOST), developed by Phillips Petroleum as an oil exploration tool.
The methodology is utilized to see if there are potentially commercial hydrocarbons beneath the surface. Soil samples are taken at a depth of almost 8 inches and then sent to Geo-Microbial Technologies laboratory for processing. The objective is to identify how many butane-specific oxidizing microbes are present in the sample. There is a direct and positive relationship between the concentration of the butane-eating microbes and hydrocarbons at depth. One way to look at it is that the microbes are Mother Nature’s own ecosystem. The microbes are naturally occurring and only occur where oil is trapped below the surface of the earth and the hydrocarbons leak to the surface. Microbial anomalies have been proven to be reliable indicators of oil and is used worldwide.
We have a rich history including a substantial amount of information and documentation. This history includes data from previous cores, logs and fire floods or in situ combustion. Fire flooding is another thermal recovery method that has been employed in the past, specifically on the Massie West Ranch. From that information, we went directly to secondary methods, skipping the conventional primary methods that only recover 10 % of the oil at a high costs. Keep in mind the savings and that the 10 % of oil that would have been extracted at a huge cost is still in place beneath the earth’s surface.
We initiated water flooding as our preferred method of production. With water flooding, selected wells in the production zone are converted into injection wells which push oil to the surrounding producing wells. Our reservoir characteristics of porosity, permeability and viscosity are exceptionally favorable for water flooding.
The difference between a steam flood and a water flood is the introduction of heat to change the viscosity of the oil. Depending on the viscosity of the oil, water flood is favorable over steam flood due to the cost to generate the steam. It is a function of pricing and economics as to which method is most practical in an individual application.
Steam flooding is prevalent in the industry. However, we have found that when the surfactant specifically formulated for our leases is combined with water flooding, the result is much more economical. The injection of targeted surfactants to our oil composition can economically reduce the viscosity of the oil similar to that of steam. We have successfully proven at Schenkel and Massie West Ranch leases that water flooding is the optimum recovery method.
The use of our Oil Composition Reports, the expertise of our Landman who specializes in the use of Surfactant and the development of the specified surfactant for our oil has proven to be a success.
The use of water flooding can still become costly because of the need for large amounts of water to extract the oil. In our case we have our own substantial water supply running beneath the earth’s surface on each lease, thereby eliminating the middle man. Although there is some cost payable to the mineral owner, it is minimal in comparison to buying water and then transporting it to the site.
The Tex-Jet is a unique lift system that is used to move produced fluids up the tubing with no downhole moving parts by utilizing bottom-hole pressure and then gas injection pressure. With this system, no gas lift valves, tubulars, downhole pumps or rods are required. These are expensive, time consuming and potentially dangerous to install, and typically have a high maintenance cost. This system also eliminates the possibility of obstruction. If the lift system happens to become clogged, only back pressure is required to resolve the problem. There is also no need to replace the Tex-Jet as is typically the case with other devices due to the quality of the 4140 heat treated stress relieved steel. This system has been successfully used by major companies, such as Chesapeake, XTO, and OEG.
S.O.S. using a heating device, is an instrument that assists in changing the viscosity of the oil to improve the ability to separate oil from the water. The removal of the water prior to sale provides a high quality product that is essential to revenues.
Viscous oils are recovered by pushing through the reservoir formations. Most commonly used medium is water, steam, fire,etc. When the oil is recovered, it contains a significant amount of water in emulsion form. In order to be commercially viable, the water needs to be removed. Heat has been generally used with the addition of expensive chemicals to help separate (dewater) oil and water.
This method using "heater treaters" or "hot oil trucks" is very expensive, around $10/BBL, and not always consistent, thereby adding to the cost.
The S.O.S. machine/process is specifically designed to economically address the problem in the field, with quick turnaround and at low cost.
Emulsified viscous oil is pumped by S.O.S. from the storage tank through the on-board heat exchanger circuit, where carefully controlled heat pressure and flow volume are monitored and automatically adjusted. During the process cycle, the oil is then returned to the top side of the storage tank using a specifically designed nozzle. This causes gentle swirling agitation, enhancing the separation process (dewatering). The process continues until sufficient heat and agitation has caused the water droplets to settle to the bottom of the tank where it is removed for reusing. This process takes about 3.5-4 hours to process a 210/BBL storage tank depending on ambient temperature. There are no chemicals used by S.O.S., only careful control of flow pressure and temperature.
Treatment in the field has consistently yielded zero BS&W at ambient temperatures of 50-60 degrees Fahrenheit and the fuel cost to process a 210/BBL tank is $120 (approximately 57 cents/BBL) at current energy prices.
We are planning to use horizontal wells for production and injection, each with up to 2,000 feet long horizontal legs. The architecture of the reservoirs within the Permian Basin, the consolidation and nature of the rock, contribute to an ideal scenario for the efficiency of water flooding.
Our unique strategies and reservoir characteristics allows us to be very economically successful in the production of oil at our leases because we
utilize: time tested technologies - communication with surrounding fields - favorable regulatory environment - low cost of production
- cutting edge technologies - daily monitoring of existing large reserves by our highly qualified operating team -