SAFOD Main Hole This will be the last message of the day for the summer as Phase 2 of SAFOD comes to a close following the successful completion of last night’s hydraulic fracture test. The open hole below the 7-inch casing is currently being cemented, and then the SAFOD borehole will ready for use as a long-term fault observatory. Interested scientists should periodically check the SAFOD website, as various types of new data will be posted when they become available. Scientific results from Phase I, as well as preliminary results from Phase 2, will be presented in a special session at the American Geophysical Union meeting in December 2005 in San Francisco (www.agu.org). Phase 3 (continuous coring of multi-laterals) will get underway during the summer of 2007. Image of the day. A parting shot of the SAFOD rig, which will be taken down and moved off site over the next week. Phase 1 (2004) / Phase 2 (2005) History Date Image of the Day Message of the Day 08/28/2005 This will be the last message of the day for the summer as Phase 2 of SAFOD comes to a close following the successful completion of last night’s hydraulic fracture test. The open hole below the 7-inch casing is currently being cemented, and then the SAFOD borehole will ready for use as a long-term fault observatory. Interested scientists should periodically check the SAFOD website, as various types of new data will be posted when they become available. Scientific results from Phase I, as well as preliminary results from Phase 2, will be presented in a special session at the American Geophysical Union meeting in December 2005 in San Francisco (www.agu.org). Phase 3 (continuous coring of multi-laterals) will get underway during the summer of 2007. more... 08/27/2005 At 3:00 am our coring operations ended successfully as the core barrel reached the rig floor. The science team was on site for immediate core handling, which included marking, sectioning, and subcoring. The core barrel contained 12 feet of 6-inch diameter core, and the core has already been taken to Bakersfield for spectral gamma logging and is on its way to the USGS in Menlo Park. Processing of the core will start on Monday and last throughout next week. On site at present we are almost ready to start the hydraulic fracture test as we attempt to measure the least principal tectonic stress at a vertical depth of over 10,000 ft on the northeast side of the San Andreas Fault! more... 08/26/2005 Our coring efforts are going very well, with the core barrel advancing at a rate of about 4 feet per hour. After the core reaches the surface, some time late tonight, we will cut and box the core, take subcore samples for formation fluids/gas analysis, and begin preparing for tomorrow's hydraulic fracturing test. more... 08/25/2005 This morning we finished drilling through the cement at the bottom of the casing and continued to drill through six feet of fresh rock. We have decided to stop drilling at this depth (13,090 ft) and proceed with the coring, so the core barrel should go into the well late tonight or very early tomorrow morning. We expect the core to come to the surface some time tomorrow. For the remainder of today, caliper and bond logs are being run in the casing to inspect the condition of the well and the quality of the cement job. more... 08/24/2005 The 7-inch casing has been successfully cemented in place, and the drilling crew is currently working to clean the cement out of the bottom of the hole. After this is completed, we will drill approximately 30 feet of new hole and continue to collect cuttings samples. Scientists from the USGS will be arriving towards the end of the week as we begin coring operations. 08/18/2005 Now that our open-hole logging and sampling program is completed, the hole will be cleaned and cased and the casing cemented in place over the next 4-5 days. During that time we will be off line until we are ready to initiate coring operations out the bottom of the cased hole. more... 08/17/2005 Today we acquired about 60 sidewall cores from various intervals of the SAFOD borehole. We are now rigging up to condition the borehole for setting casing, which will start in a few days. more... 08/16/2005 Geophysical logging was completed last night. A sidewall coring tool is being run into the hole tonight in an attempt to obtain samples from multiple depths in the hole. more... 08/14/2005 After a successful logging run last night with the super-combo (resistivity, density, neutron and gamma ray) and the sonic tools, acoustic and electrical image logging is well underway. This logging run should be completed later this evening and the science team will use the image logs to finalize where the sidewall cores will be obtained. more... 08/13/2005 We completed our first logging run early this morning and are getting ready for the second. Meanwhile geologists and geophysicists on the science team use some data from the first run along with cuttings analyses and mud gas information to determine the best places in the hole to aim for side-wall cores. more... 08/12/2005 The first pipe conveyed logging run is underway and a preliminary look at the data indicates that the data from this run correlates very well with the LWD data obtained during drilling. more... 08/11/2005 We are currently tripping out of the hole after reaming and conditioning for the last 24 hours. The first geophysical logging run through the San Andreas fault at seismogenic depths will begin during the early hours of tomorrow morning. more... 08/10/2005 Reaming of the borehole is underway and the science team has been busy today taking samples of cuttings from the reaming and catching up on data archiving and processing of samples previously collected. more... 08/09/2005 The science team is happy to announce that drilling of SAFOD was completed today at noon when we reached a total depth of 13082 feet, approximately 150 feet northeast of the surface trace of the San Andreas Fault. Reaming and conditioning of the borehole begins tonight in preparation for geophysical logging operations tomorrow. more... 08/08/2005 SAFOD is now approximately 13,000 feet deep. Drilling is expected to continue until tomorrow morning. more... 08/07/2005 Drilling began this morning at 11:50 am with what is likely to be the last bit that will be used during SAFOD Phase 2. We anticipate a further 35 hours of drilling time. The rate of penetration is averaging about 10 ft/hr and the cuttings samples continue to be predominantly shale with less siltstone. more... 08/06/2005 At a depth of 12,804 feet we are tripping out of the hole to replace the drilling bit and we expect to continue drilling tomorrow around noon after reaming the borehole. 08/05/2005 As we drill ahead at ~ 12, 700’, evidence accumulates that we’re probably drilling in Franciscan formation rocks on the north east side of the San Andreas fault . Several fragments of Inoceramus, a Cretaceous age fossil, have been found in the cuttings. In addition, the magnetometer on the directional drilling system has begun detecting significant variations of the magnetic field, a phenomenon consistent with the presence of highly magnetic serpentinite associated with the Franciscan. 08/04/2005 Drilling has resumed at 12,570 feet (measured depth) following a routine bit replacement. Cuttings samples (and a fossil fragment from the northeast side of the fault) have been sent to Menlo Park for analysis. Drilling mud samples are being analyzed for grain size distribution and composition to see if there is a change in clay content in the mud before, during and after drilling through the fault zone. more... 08/03/2005 Yesterday, August 2nd, at about 18:35 PDT, we drilled through a very significant fault zone located about 100m SW of the San Andreas surface trace, and within the region where microearthquake data indicate the San Andreas fault to be at 3 km depth. Our first indication of entering the fault zone was a modest increase in drilling rate starting at about 2:30 yesterday afternoon. This early break was comparable to what we've seen when drilling through minor faults or weaker lithologic units - an increase from ~6-9 ft/hr to 12-15 ft/hr. At the same time, an increase in mud gas was observed, particularly radon, hydrogen, CO2 and hydrocarbons. Over the hours that followed we observed a number of very distinct drilling breaks, including one in which we drilled for several feet at rates as fast as 41 ft/hr. Overall, the fault zone appears to be several tens of meters wide with distinct zones characterized by faster drilling. Cuttings from the fault zone itself contain trace amounts of serpentine minerals. Cuttings from the northeast side of the fault are siltier, but it is not yet certain that we have crossed into rocks of the Franciscan formation on the northeast side of the San Andreas. Additional samples will help clarify this. We will continue to collect cuttings, monitor gas, and perform on-site analyses until the next bit trip, which is scheduled for 2:00 am tonight. Drilling should then resume around mid-day tomorrow. We will continue to post frequent updates to this web page throughout the coming days. more... 08/02/2005 Today SAFOD reached a depth of a depth of 12,452 feet at an average of 7 feet per hour. Geologists on site have noticed a slight increase in the amount of crystalline material and calcite veining in the cuttings. more... 08/01/2005 Problems arose with the top drive when drilling began this morning. Mechanics have been working on it all day and drilling should resume tonight. more... 07/31/2005 Drilling has progressed well for the past 24 hours. With our total depth at just over 12,400 ft, we'll be tripping out overnight for a bit change. more... 07/30/2005 At 5:30 this morning the bit hit bottom and we started drilling ahead! We are currently at 12,250 ft and making good progress while the science team gets back to work collecting and analyzing new samples. more... 07/29/2005 Reaming operations were completed overnight, and the open hole between the casing shoe at 10,005 ft and our current depth of 12,181 ft is in good shape. We are now tripping out of the hole to install the steerable drilling assembly. more... 07/28/2005 Reaming operations have gone on all day without difficulty, conditioning both the hole and mud system in order to resume drilling tomorrow. more... 07/27/2005 Activities at the site today included checking the bottom hole assembly, tripping in the hole for a reaming run, and conditioning the drilling mud. We should be reaming overnight and then going back into the hole to resume drilling tomorrow. more... 07/26/2005 At 12:45 this afternoon, we started tripping out of the hole, having successfully retrieved the drill pipe and bit that had been stuck in the hole. It will take some time to work on the mud system and check the bottom hole assembly. We will then attempt to ream and condition the hole again. If that is successful, drilling will likely resume in 36 to 48 hours. more... 07/25/2005 The first step in the process of getting unstuck went very well today. The pipe was successfully "backed off" one section of drill pipe below the drilling jars at a depth of 11,658', as intended. About 350' of pipe, and the bit, are left in the hole. We know from the logging-while-drilling data that the section of the hole that contains "the fish" was in good shape at the time it was drilled (the hole size was almost everywhere in gauge). There are several sections of enlarged hole, but these extend over relatively short intervals. We are tripping into the hole with heavy duty jars, an intensifier and bumper sub to try to retrieve the fish. more... 07/24/2005 Wellbore stability problems developed during the bit trip Saturday, making it necessary to back-ream out of the hole. The trip out was completed successfully despite two very tight intervals where the pipe was stuck briefly. This morning, a reaming trip was started in order to clean out the well and circulate in slightly denser mud. During the reaming trip into the hole, with the bit at a depth of 12,030 feet (~150 feet off bottom) the pipe got stuck. Actions are currently being taken to remedy the situation. more... 07/23/2005 After drilling to 12,180 feet we are tripping out of the hole to change the bit again. We'll be back on bottom and drilling tomorrow morning. Although a significant change in lithology occurred at 12,120 ft, we do not appear to have crossed the San Andreas fault yet. more... 07/22/2005 We've been drilling ahead with bit #9 since very early this morning. We are now at 12,075 feet and progressing at about 7 or 8 feet per hour. more... 07/21/2005 The last drilling phase (bit #8) ended several hours prematurely yesterday when the drill pipe showed a sudden increase in torque. When the pipe was tripped out of the hole, it was discovered that the drill bit had lost one of its three cones. This has caused a delay of about 18 hours as we've needed to make a trip into the hole with a mill to grind up the cone on the bottom. We expect to resume drilling at around midnight. more... 07/20/2005 Another bit trip gives us a brief reprieve from the intense scientific activity of the last few days, including sample collection under a full moon. We will be back on site when drilling resumes in the early morning hours tomorrow. more... 07/19/2005 We continue to drill, a little faster now with our new bit, and we expect to see strong evidence of being in or near the San Andreas at any time. more... 07/18/2005 It was a busy day at SAFOD as we started drilling with a new bit, finalized some of our procedures for on-site, real-time mineralogical analysis, and had lots of visitors. Our current depth is 11,716 feet, and we're advancing at 5 to 10 feet per hour. more... 07/17/2005 Drilling continues slowly but steadily at rates between 3 and 7 feet per hour. We'll change the bit tonight and resume drilling tomorrow afternoon. Meanwhile we're using our scientific creativity to develop analysis techniques with materials we have on hand. more... 07/16/2005 The science team excitedly started collecting cuttings again today as drilling resumed from a depth of 11,462 ft. With real-time mineralogical and gas analysis, we are scrutinizing the material we drill through. Our goal is to identify fault materials as early as possible. more... 07/15/2005 The data from the first LWD run were dowloaded successfully and reveal important geological characteristics and potential shear zones in the Phase II hole. Drilling and logging are set to resume tonight or early tomorrow morning. The brief hiatus provided the geology team time to generate and closely examine thin sections of the cuttings. more... 07/14/2005 While the drilling crew has been pulling out of the hole to change the bit and download the LWD data, the science team has been busy setting up equipment for real time mineralogic analyses of the cuttings that will aid in identifying the fault. more... 07/13/2005 Drilling continues with LWD. A team of geologists, with additional analytical equipment, have arrived on site to assist in real time lithologic analyses as we approach the San Andreas Fault. more... 07/12/2005 We have been Logging While Drilling (LWD) since last night and will soon complete logging in the already-drilled section of the borehole. Once TD is reached, rotary drilling with LWD will commence and the science team is anxiously watching the real-time logging data help characterize the rocks in the San Andreas Fault Zone as they are penetrated by the borehole. more... 07/11/2005 Nabors crew runs LWD tools into the SAFOD hole. We will start by logging the 387 meters of open hole drilled in Phase II. more... 07/10/2005 After a successful reaming trip the Schlumberger field engineers are making the final preparations to the LWD logging tools in anticipation of beginning the logging run around midnight. more... 07/09/2005 The crew is carrying out a variety of tasks while preparing for a trip into the hole to condition the mud (after the appreciable down time) and hole reaming (following the directional drilling that preceded the top drive going down), all in preparation for the resumption of drilling with LWD (logging while drilling) tools on Sunday or Monday. 07/08/2005 Today the rig crew is reinstalling the repaired top drive and we are set to resume drilling towards the San Andreas fault. We anticipate that we will begin reaming and conditioning the hole later this evening. more... 07/03/2005 Unfortunately the top drive is giving us trouble again. The motor failed and must be repaired in Bakersfield. Due to this, drilling operations will be put on standby for a few days. We plan to be drilling again by the end of the week. We will continue posting updates when the drilling resumes. 07/02/2005 After two and half hours spent trying to retrieve a core, unforseen problems stymied our attempt and at 7pm this evening the core barrel was pulled out of the hole and contained only a few rock fragments. Nonetheless, scientists are excited about analyzing the gas content and mineralogy of these rocks from the crust adjacent to the fault zone. We are now proceeding to ream and condition the hole in preparation for the LWD as we continue our journey to the San Andreas Fault. more... 07/01/2005 The top drive has been repaired, a new schedule has been set for the coring run. The borehole conditions have been evaluated, and are optimal to proceed with the coring. Tonight we will start the core run! more... 06/24/2005 The drilling operations were forced to stop due to a failure in the top drive transmission system. The top drive must be repaired in Bakersfield, which will take several days. The failure occurred when we were about to start coring, which forced us to delay the coring schedule. Hopefully, the coring and Logging While Drilling will start sometime next week. We will be offline while the top drive is being repaired. more... 06/23/2005 Today we reached a measured depth of 11,270 ft. We have stopped drilling and are now rigging up for coring. Around midnight we will start the first core run for Phase II of the SAFOD project! more... 06/22/2005 Drilling goes on as planned. The last sample came from a measured depth of 11,000 ft ! We are drilling through fine grained sediments. The first samples have already been sent the USGS office in Menlo Park for XRD analyses. Each day we are closer the San Andreas fault zone! more... 06/21/2005 Equipment and staff are beginning to arrive for coring operations and LWD deployment, which will take place after this latest bit wears out. Meanwhile, over the next two days we will continue to make new hole and collect cuttings samples for petrographic, X-ray diffraction, and other analyses. more... 06/20/2005 We've stopped drilling for a bit trip at 10,900 ft. We should be back on bottom with a new bit first thing tomorrow morning. more... 06/19/2005 Today was a "No News is Good News" day here at the site. We are making consistent drilling progress with a steady rate of penetration of about 10 ft/hr, and we've been in a fine-grained, sedimentary lithology since late last night. We will probably need to change bits tomorrow, and then we will proceed to drill to 11,150 ft before we begin our first Phase II coring effort. more... 06/18/2005 It was back to business here at SAFOD today, as we drilled ahead approximately 60 ft this afternoon and plan on making plenty of progress throughout the next couple of days. We've gone from a dark, shaly formation to a lighter sandstone or quartzite. A variable rate of penetration suggests that we are changing lithologies quickly and/or going through a highly fractured material. Further drilling will help us better understand how close we are getting to the San Andreas! more... 06/17/2005 Today was a slow day for the scientists. The drillers are reaming the well below the 10,005 ft casing shoe, and we will resume drilling as soon as that is completed. more... 06/16/2005 Our drilling crew worked hard today to free the drill pipe from a tight spot below the last casing shoe at 10,005 ft. Now we are pulling out of the hole to install a new bit before resuming drilling. Our current hole depth is 10,484 ft. more... 06/15/2005 While the SAFOD Drilling Advisory Committee met in Paso Robles today, work at the drill site continued as usual. more... 06/14/2005 All of us at SAFOD send out a hearty congratulations to our own Naomi Boness, who was hooded by Mark Zoback at Stanford's commencement ceremony Sunday. more... 06/13/2005 We're drilling!!! more... 06/12/2005 Preparations for the SAFOD Phase II well continued today. The science team is anxious to see some new samples, and we anticipate drilling will begin within the next 24 hours. more... 06/11/2005 As the start of drilling approaches mud engineer Alan Bartley is preparing the drilling mud while the scientists and mudloggers are fine tuning their labs. more... 06/10/2005 The hydrofracture experiment wrapped up shortly after dawn this morning. Getting the rig ready for the start of drilling is now top priority on site. more... 06/09/2005 It's been a very full 24 hours, starting with fluid sampling in the early morning hours and ending with a hydrofrac scheduled for late tonight. The fluid sampling went very well, capturing both pore fluids and gases from the bottom of the 10,000-foot well. more... 06/08/2005 Our drilling crew lowered over 10,000 feet of pipe into the well today! Fluid sampling operations will take place throughout the night. We're on a 24/7 schedule here at SAFOD. more... 06/07/2005 The site was a busy place today as final preparations were made to the rig, drilling pipe was unloaded, and scientists started arriving for upcoming fluid sampling and hydrofracturing experiments. more... 06/06/2005 The Phase II drilling season for the SAFOD Main Hole has begun!!! Today we had two kinds of drives on site - a top drive and a cattle drive (see additional photos)! The rig is up, and preparations are in full swing. We expect to get the science under way within the next 48 hours. Please check back for daily updates. more... 03/02/2005 Scientists from across the US met at the core repository in Texas A&M University to examine the cores from Phase 1 of drilling. Meanwhile preparations for Phase 2 drilling are ramping up. The site characterization team is preparing for the last suite of experiments designed to accurately locate the target earthquakes.