Set a record for single well production in China.

Chedang fault in Wangchang structure is still a normal fault after the review of Siwu seismic profile. Well Shen Qian 5 is located at the highest point of the upper wall structure of the fault. It is speculated that the gypsum-salt layer has high plastic strength and can play a role in plugging faults, while the fault itself has a small fault distance, which will not adversely affect oil and gas enrichment.

The 3007 drilling team once again shouldered the heavy responsibility of Well No.5 in Wangchang Structure, vowing to achieve ultra-high oil and gas production. With the experience and lessons of Submersible Well 4, drilling engineering has been innovated and strict operation measures have been taken.

(1) exploration target layer: in addition to tracing the original oil and gas layers in Well Shen 44, the oil and gas layers below 1500m are mainly explored.

(2) Drilling technology: Chen Chengjun, Wang Guixin, etc. Vertical well drilling measures will be checked and formulated to ensure the design well depth is reached. And solve a series of difficulties from drilling to casing running. For example, the technical problems of roller cone drilling: the weight of oil layer casing exceeds the load and lifting capacity of derrick, the annular space between the existing 148 mm bit and 1 14 mm oil layer casing, and water cross at the bottom of casing, etc.

(3) Mud technology: Mud is called the blood of drilling engineering, which plays a key role in ensuring the smooth drilling and protecting the borehole wall, and plays a key role in the success or failure of drilling. Especially in gypsum and salt areas, it plays a destructive role in conventional mud preparation, and it is easy to cause major drilling accidents. It is necessary to overcome the backwardness of mud technology and carry out technological innovation. This special task was entrusted to Mei Shixin. From theory to practice, he conducted in-depth discussions and tackling key problems in mud types and treatment agents. Firstly, the waste liquid of sulfite pulp produced in Wuhan was used as a diluent to control the viscosity of slurry and cutter. After the initial results, the powder of various gum-containing plant stems and leaves was tried to be used as protective glue to control water loss. Then, in cooperation with the Exploration Institute of the Ministry of Geology, Fe-Cr lignosulfonate was developed as an efficient diluent and cottonseed saponin as a defoamer for the first time in China, which basically met the requirements of drilling technology, solved the control of gypsum and salt mud properties and ensured the smooth drilling. According to the current standards, the invention should reach the advanced level at home and abroad, and obtain the national technology patent.

(4) Cementing technology: single stroke, double pumping, double knife and double safety are adopted. This technology can make the cementing quality basically meet the requirements of trial production without channeling.

(5) Logging technology: Fully automatic lateral logging is mainly used. Due to the influence of gypsum and salt mud, the measured resistivity curve is a smooth straight line and can not be used at all. After many tests and comparisons, it is finally found that the caliper curve is used to judge the sand and mud layer, which plays an auxiliary interpretation role.

Due to the effective technical measures of the above five reforms, the design task of Deep Well 5 was successfully completed, and the dangerous situations that occurred many times during drilling were solved.

In June, 1966, 1 1, the drilling and completion depth of the submersible well No.5 1985.73 m, 1253 ~ 1367 m, and the total thickness is 36.8 m. By comparison, it is equivalent to the oil layer below 4 wells 1500m, and it is confirmed that 5 wells are higher than 4 wells, occupying the highest structural point. When drilling to the depth of 1295 ~ 1299 m, strong gas immersion and oil spill occurred. When drilling to1605 ~1932m, five new oil layers with a total thickness of 23.8m were drilled. When drilling to1924.5m, a strong blowout suddenly occurred. At that time, the specific gravity of mud was 1.3, and the blowout could not be suppressed. Ground fissures appeared on the wellhead ground, and the steel plate with a thickness of 2 cm was punctured, and the blowout gate was braked urgently. The daily output of blowout is 2160m3, and about100t of sand is ejected. Hundreds of meters of ditches in the well site flow into the river. In order to prevent natural gas fire, farmers in Yili, Fiona Fang were urgently told not to use naked fire for the time being, and the generator at the well site stopped. At night, they have to use flashlights to illuminate and send militia guards. The atmosphere is very tense. The drilling crew took strict measures and immediately put into testing work. It is verified by electric logging that there are 19 oil and gas layers in the whole interval, with a total thickness of 96.7m, and the best is 12 layer with a thickness of 62.6m.. The highest permeability of the reservoir is 2589 mDarcy, and the highest oil saturation is 55%. Seven oil layers * * * 32m 1 gas layer were selected for testing, and the daily output of crude oil was 777.6 m3 (533 tons).

At that time, it set a record for the highest daily oil production of a single well in China, thus affirming Wangchang Oilfield (called Hongqi Oilfield by the Ministry of Petroleum Industry), which was commended by the Ministry of Geology again and was sent to the central news recording studio as a photographer to record the whole process of testing and blowout (the film is still kept in the data files of the factory). This well is still the most productive well in Jianghan Oilfield.

At that time, it was a miracle that the gypsum-salt basin could achieve such a high output!

I remember 1965, 10 in June, when a geological and technical symposium was held in Lintong, Shaanxi Province, it was discussed at the meeting how long the red flag of our oil and gas exploration could last. At that time, the national petroleum exploration by the Bureau of Petroleum Geology seemed to be at a low point. The discovery rate of easy-to-find and easy-to-find oil and gas is greatly reduced, and difficult-to-find or subtle oil and gas reservoirs can only be discovered through high-tech exploration. But it is more important to have new oil and gas geological theory as a guide to discover new fields. The discovery of Wangchang Oilfield has opened up a new field of petroleum exploration in gypsum-salt basin and achieved the predetermined goal of super-high oil and gas production.

In the same year, according to the document of the Ministry of Geology (1966) 13, Wangchang structure was reported to Jianghan Petroleum Exploration Command of the Ministry of Petroleum Industry for exploration and development.

After the deep well 5 test, I met Feng, commander of Jianghan Petroleum Exploration Command in Wangchang. At that time, he was going to Wangchang to survey the well site and prepare to deploy several exploration wells. He asked me to give them advice on the well site. I suggested that the site could be selected under Chedang fault in the southeast of Shenshen 5 well, and later Hong 2 1 well was drilled, and industrial oil flow was also obtained.

It took only nine years from the beginning of oil and gas exploration to the discovery of oil and gas fields in Jianghan Basin, and the cumulative drilling footage was 50,527 meters, including deep wells15,923 meters. Six wells have been drilled in Wangchang structure, with a total footage of 7399.23m, including 3987.83m deep wells (oil and gas hit rate 100%). According to the speed comparison of oil and gas exploration history at home and abroad, it is also at a high level, especially in gypsum-salt basin, where two exploration wells can be drilled to obtain high-yield oil and gas flow, which is rare in the world.