Diablo Range Wild: Laguna Mtn & Joseph Grant
Posted: Tue Dec 08, 2020 10:27 pm
I had intended to do some North Sierra fishing into November but my schedule and fall storms nixed that. In the meantime I shifted to "off season" geology hiking mode.
Part I. Laguna Mtn Recreation Area
The first trip was part of teaching a geologic mapping exercise for my structural geology class at Fresno State. My usual area (Sunol Regional Wilderness, SE Bay Area, NW Diablo Range) was closed owing to fire damage and its aftermath, plus there were some issues with camping. Taking the advice of a really sharp new graduate student, the class headed to the Laguna Mountain recreation area, E of King City (or W of Coalinga, depending on your point of view). We were there from Nov. 12-15. There are two campgrounds. They are primitive (no running water and pit toilets only) but they are clean and spacious. The elevations, by Diablo Range standards, are fairly high. We were camped at an elevation of about 2900' and the high point of the area, Laguna Mtn is a bit over 4500'. There are several maintained trails, some of which are essentially dirt roads. There is a rugged canyon, called The Gorge, which we tried to force (ie clamber up, off trail). This worked until we got to the dry Laguna Falls, which must be a pretty spectacular place when the water is running (there is a gorgeous photo of it on the recreation area brochure). We did this on day 2 (Nov 13) and by the time we got boxed in (had already climbed past one or two cliff outs) we were running out of time to do the big detour necessary to climb by Laguna Falls plus both me and my grad student had reinjured our knees, so we weren't in our best off trail scrambling mode.
Nov. 14 the 3rd of the 4 days I figured on exploring to the southern edge of the map area I had assigned to the students: this was the summit of Laguna Mtn. From a geologic standpoint this turned out to be a waste of time, but the fact that all the students more or less summited (it's a rounded summit and they stopped about 1/4 mi and 50' elev short of the true summit after climbing the most difficult stuff) testifies to their adventurous spirit. The last part of the ascent is by a use trail that winds through the brush. We made two attempts because we were mislead by some logs placed across the real use trail by peak baggers (apparently this is some local peak bagging target) who apparently prefer a route that went east of the limit of what I had put on the students' topo base. In any case we tried to follow the peak bagger's route and found ourselves in horrible brush. After several really bad passages we found ourselves totally hemmed in about 200' below the summit, so we turned back. It was getting a bit late and I told the students we really hadn't seen much geology beyond where we'd gone the day before so I advised aborting the summit climb. The students insisted on finishing the climb though, so when we got back to the "split" where logs had been laid across the "real" goat trail (which is the one shown on the recreation area topo map) we took the "real" trail back up the climbed the mountain. There was a logical stopping place after the main difficulties had been surmounted and as the students rested I limped up to the top (the knee was in pretty bad shape from the injury the day before). One of the rock samples I picked up at the summit turned out to be one of the most important research samples I've ever collected, but I wouldn't know that until I returned to campus, cut thin sections, and examined it under the microscope. During the descent, my knee blew out again when I slipped, so I was in a world of hurt hiking the rest of the way out. It was dark by the time we all made it back to the camp (which was also our kickoff point). All told (counting the detour) the hike was something like 8 miles round trip with 3200' of elevation gain which made it the hardest hike done by a Fresno State geology class in modern history.
Part II. Joseph Grant County Park to the Arroyo Hondo canyon.
After two weeks resting the tormented right knee I figured it was good enough to road test with a bit of a run, so I took a 2 mile run Sunday before last and it went off pain free (including no pain afterwards). At that point I figured I could do another crazy geology hike, this time bringing along a Bay Area geologic hiking companion, given that this hike was not one I wanted to try alone. The target for the Friday Dec. 4 geologic exploration was the bottom of one of the most savage canyons in the Diablo Range, the canyon of the Arroyo Hondo, N of Mt Hamilton. I had been told of this place over 30 years ago by a geologist who advised me to check it out, telling me that I was one of the few geologists physically able and crazy enough to try it. I didn't have a scientific motivation to go back then, whereas do now, so I've been thinking of this place for awhile. I thought to exploit the SCU burn, thinking that it would have cleared some brush off the descent. To hit the public part of this canyon you have to go in via Joseph Grant County Park (on the Mt Hamilton Rd): it is about a 4.5 mi hike with something like 1600-1700' of gain to the kickoff point on the rim (at least to the kickoff point I tried). This all went off OK but I lost concentration at one point in the descent and injured the right knee again, about 700' above the bottom. At 400' above the bottom things really start getting serious and my friend said it exceeded his sketch tolerance, so I gave it a go the rest of the way, only to throw in the towel when my own sketch tolerance topped out 150' from the bottom. Did trying this on a bad knee influence my decision? Maybe, but I think it would have been wise to turn around at the point even if I was 100 percent. Would the geology have been worth the trouble if I had made it down? Doubtful, based on what I could see, but you never know. The best exposures are in fact in the bottoms of canyons like this but I don't think the sort of geologic relationships I was looking for were there, based on what I could see.
Over winter break I'm already scheming on potentially better canyon climbs (but not quite as nasty as this one), with the top targets being in Henry Coe. I will also plan to return to Laguna Mtn and tie up some loose ends. And, of course, there will also be coastal fishing adventures.
Part I. Laguna Mtn Recreation Area
The first trip was part of teaching a geologic mapping exercise for my structural geology class at Fresno State. My usual area (Sunol Regional Wilderness, SE Bay Area, NW Diablo Range) was closed owing to fire damage and its aftermath, plus there were some issues with camping. Taking the advice of a really sharp new graduate student, the class headed to the Laguna Mountain recreation area, E of King City (or W of Coalinga, depending on your point of view). We were there from Nov. 12-15. There are two campgrounds. They are primitive (no running water and pit toilets only) but they are clean and spacious. The elevations, by Diablo Range standards, are fairly high. We were camped at an elevation of about 2900' and the high point of the area, Laguna Mtn is a bit over 4500'. There are several maintained trails, some of which are essentially dirt roads. There is a rugged canyon, called The Gorge, which we tried to force (ie clamber up, off trail). This worked until we got to the dry Laguna Falls, which must be a pretty spectacular place when the water is running (there is a gorgeous photo of it on the recreation area brochure). We did this on day 2 (Nov 13) and by the time we got boxed in (had already climbed past one or two cliff outs) we were running out of time to do the big detour necessary to climb by Laguna Falls plus both me and my grad student had reinjured our knees, so we weren't in our best off trail scrambling mode.
Nov. 14 the 3rd of the 4 days I figured on exploring to the southern edge of the map area I had assigned to the students: this was the summit of Laguna Mtn. From a geologic standpoint this turned out to be a waste of time, but the fact that all the students more or less summited (it's a rounded summit and they stopped about 1/4 mi and 50' elev short of the true summit after climbing the most difficult stuff) testifies to their adventurous spirit. The last part of the ascent is by a use trail that winds through the brush. We made two attempts because we were mislead by some logs placed across the real use trail by peak baggers (apparently this is some local peak bagging target) who apparently prefer a route that went east of the limit of what I had put on the students' topo base. In any case we tried to follow the peak bagger's route and found ourselves in horrible brush. After several really bad passages we found ourselves totally hemmed in about 200' below the summit, so we turned back. It was getting a bit late and I told the students we really hadn't seen much geology beyond where we'd gone the day before so I advised aborting the summit climb. The students insisted on finishing the climb though, so when we got back to the "split" where logs had been laid across the "real" goat trail (which is the one shown on the recreation area topo map) we took the "real" trail back up the climbed the mountain. There was a logical stopping place after the main difficulties had been surmounted and as the students rested I limped up to the top (the knee was in pretty bad shape from the injury the day before). One of the rock samples I picked up at the summit turned out to be one of the most important research samples I've ever collected, but I wouldn't know that until I returned to campus, cut thin sections, and examined it under the microscope. During the descent, my knee blew out again when I slipped, so I was in a world of hurt hiking the rest of the way out. It was dark by the time we all made it back to the camp (which was also our kickoff point). All told (counting the detour) the hike was something like 8 miles round trip with 3200' of elevation gain which made it the hardest hike done by a Fresno State geology class in modern history.
Part II. Joseph Grant County Park to the Arroyo Hondo canyon.
After two weeks resting the tormented right knee I figured it was good enough to road test with a bit of a run, so I took a 2 mile run Sunday before last and it went off pain free (including no pain afterwards). At that point I figured I could do another crazy geology hike, this time bringing along a Bay Area geologic hiking companion, given that this hike was not one I wanted to try alone. The target for the Friday Dec. 4 geologic exploration was the bottom of one of the most savage canyons in the Diablo Range, the canyon of the Arroyo Hondo, N of Mt Hamilton. I had been told of this place over 30 years ago by a geologist who advised me to check it out, telling me that I was one of the few geologists physically able and crazy enough to try it. I didn't have a scientific motivation to go back then, whereas do now, so I've been thinking of this place for awhile. I thought to exploit the SCU burn, thinking that it would have cleared some brush off the descent. To hit the public part of this canyon you have to go in via Joseph Grant County Park (on the Mt Hamilton Rd): it is about a 4.5 mi hike with something like 1600-1700' of gain to the kickoff point on the rim (at least to the kickoff point I tried). This all went off OK but I lost concentration at one point in the descent and injured the right knee again, about 700' above the bottom. At 400' above the bottom things really start getting serious and my friend said it exceeded his sketch tolerance, so I gave it a go the rest of the way, only to throw in the towel when my own sketch tolerance topped out 150' from the bottom. Did trying this on a bad knee influence my decision? Maybe, but I think it would have been wise to turn around at the point even if I was 100 percent. Would the geology have been worth the trouble if I had made it down? Doubtful, based on what I could see, but you never know. The best exposures are in fact in the bottoms of canyons like this but I don't think the sort of geologic relationships I was looking for were there, based on what I could see.
Over winter break I'm already scheming on potentially better canyon climbs (but not quite as nasty as this one), with the top targets being in Henry Coe. I will also plan to return to Laguna Mtn and tie up some loose ends. And, of course, there will also be coastal fishing adventures.