Cuttings are the Rodney Dangerfield of the oil patch—they get no respect. The perceived value of cuttings is often so low that many wells are now drilled without catching cuttings.

Today we hope to lift up cuttings by discussing Rock Volatiles Stratigraphy, RVStrat, also known as Volatiles Analyses Services or VAS.

RVStrat is a patented gentle extraction and analyses technique I invented that utilizes a cryogenic-trap mass spectrometry system for quantitative volatiles analyses. RVStrat analyzes and makes logs of present-day oil, gas, formation water, CO₂, Helium, Sulfur gases, and other volatiles from old and new, OBM or WBM, PDC bit cuttings. These data are being used in oil and gas E&P, CCS, Helium, and Geothermal ventures. The disaggregated rock mechanical strength of each sample is measured in terms of the samples linear compression caused by squeezing with a force of 2 tons.

Examples are shown of wells where RVStrat identifies zones in laterals likely to produce more water and less oil (Figs. 1 and 2). Leaving these zones behind pipe uncompleted could reduce water production and water disposal costs and decrease completion costs.

RVStrat also determines reservoir quality. Tight rocks maintain their oil and gas; good reservoir rocks do not. Faults and fractures are located. Migration pathways, product type and quality, oil fractionation via gas stripping, location of tar, CCS reservoir site evaluation, water saturation and oil versus water wettability, and the list of applications goes on.

I have been inventing and building machines to analyze cuttings volatiles for 40 years. One of my earliest inventions was Fluid Inclusion Stratigraphy (FIS), which I invented at Amoco Research in the 1980s and is now at Schlumberger, followed by Fluid Inclusion Volatiles (FIV) that I invented after resigning from Amoco and which I sold 5 years later to ExxonMobil.

While fluid inclusions are incredible resources, they have not proven capable of the  day-to-day heavy lifting and rapid turnaround times required in oil patch operations.

Fluid inclusions in cuttings are now often too small to be analyzed.The advent of PDC bits greatly reduced the size of cuttings particles, often to less than 1 millimeter in diameter, and the fluid inclusions in these small diameter PDC bit cuttings are often compromised.And the shale revolution moved us into very fine-grained reservoir rocks whose fluid inclusions are incredibly small.

Time and space are also challenges for fluid inclusions. Importantly, fluid inclusions trap fluids in the past. And fluid inclusion formation is not uniform in the subsurface. Often oil and gas charged reservoirs do not contain abundant oil or gas fluid inclusions, whereas wet or tight reservoirs may have abundant oil inclusions.

So, after 25 years, I pivoted away from fluid inclusions to focus on inventing and applying technology to analyze present-day fluids in cuttings. RVStrat will help you produce more oil, more gas, and less water.

Happy Holidays Everyone!!!

BIOGRAPHY: Mike Smith received a B.A. in Geology from Rutgers College in 1977, and a Ph.D. in Geology and Geophysics from the University of Hawaii in 1981. Mike then went on to be a Research Scientist at the University of Tulsa until 1984, and during this time Mike developed the first Mass Spectrometer system for analyzing Individual Fluid Inclusion Volatiles with Colin Barker. Mike joined Amoco’s Tulsa Research Center in 1984 and worked there until 1994. At Amoco Research, Mike invented Fluid Inclusion Stratigraphy (FIS) now owned and marketed by Schlumberger. Mike resigned from Amoco in 1994 to start Advanced Hydrocarbon Stratigraphy. Mike invented Fluid Inclusion Volatiles (FIV) at AHS, which he sold to ExxonMobil Upstream Research in 1999. Mike consulted with ExxonMobil Research until 2009. In 2010, Mike restarted AHS and developed his new technology for the gentle analyses of present-day formation fluids in cuttings and core. Mike and AHS teamed up as strategic partners with Baker Hughes in 2018 to market this technology Worldwide as Volatiles Analyses Services (VAS). Although VAS was developed as an oil and gas E&P tool, our work in the E&P sector revealed VAS’s potential as a tool for evaluating reservoir viability for Carbon Capture and Storage (CCS) via cuttings volatiles analyses during initial reservoir site selection.