Geology – Sherry Felix

Manawainui Gulch Piilani Highway

2022-12-122022-12-03Sherry Felix2 Comments

The Manawainui Gulch under the Piilani Highway was formed by Haleakala’s waters carving out a deep chasm into the earth. The Manawainui Gulch is often dry unless there’s heavy rainfall, but the views of the southern slopes of Haleakala alongside the massive chasm are stunning. This area is very windy and it’s dangerous to get too close to any of the cliff edges. As you can see, were now on the dry side of the Island.

Piilani Highway is a road with bad reputation. We found it fun to drive. The road is rough and unpaved at times. It’s a good idea to honk around blind corners. Hawaii Route 31 is 61 km (38 miles) long, running from Kipahulu to Ulupalakua. It’s a twisty, up and down roller coaster. The toughest section of the road is about 10km (6 miles) long, where the road sometimes narrows to a single lane in sharp bends. In some areas (such as at Lelekea Bay) it’s just a one-and-a-half lane bumpy road hugging the sea cliff around a blind curve. The hairpin bends are completely blind, but there is almost no traffic. Occasionally the road is closed to traffic due to landslides. Traffic is light.

Piʻilani (“ascent to heaven”) was born ca. 1577 and ruled as Mōʻī of the island of Maui in the later part of the 16th century. At the time Maui was an independent kingdom within the islands of Hawaii. He was the first Aliʻi to unite the island under a single line.

Pelham in Winter

2022-02-192022-02-20Sherry Felix25 Comments

We took a walk in Pelham Bay Park in the Bronx, New York on February 16, 2022. I replaced the skies in most of these.

I love the folded and layered metamorphic Fordham Gneiss, which is part of the Hartland Formation that forms the bedrock beneath the Bronx east of Cameron’s Line. The rock consists of granitic and garnetiferous amphibolite gneiss with numerous light-colored quartz veins and migmatite dikes. Migmatite is a type of igneous rock that forms when metamorphic processes begin to melt the rock under high temperature. Felsic minerals melt and are injected into joints, faults, and other zones of weakness in the rock. As it gradually cools, bands of feldspar and quartz crystals form along the edges of the intrusion. The center of the migmatite veins typically consist of larger crystals of feldspar and quartz. In some cases, the dikes cut across older dikes and quartz-filled veins; many are folded, or display offset by faulting. Overlying the bedrock is a blanket of glacial till. The beach is littered with large erratics derived from bedrock sources nearby. (Source: NYC Regional Geology (geologycafe.com))

After walking to the end of Hunter Island we drove to City Island for a meal at the Lobster House.

Boudinage

2021-12-192021-12-18Sherry Felix4 Comments

Revisiting an old image for reprocessing. Pelham Bay has lots of Fordham gneiss. Here is a dense article on the Bedrock Geology of New York City: More than 600 m.y. of geologic history (sunysb.edu). I love geology. It was my manor at Hunter College.

Geology lesson: Boudinage is a structure which is sometimes present in metamorphic rocks apparently as a result of tension and in which a competent bed is thinned and thickened so that it resembles in cross section a string of sausages (Webster’s).

Hunter Island granite with boudinage, Pelham Bay, NY 10/29/2001

Krysuvic

2021-08-182021-08-18Sherry Felix6 Comments

On July 20 the official self-guided trip was over, so I chose where to go. We went to Valahnuamol point. On the way we stopped at Krýsuvík geothermal area. The colors there are magnificent. The solfatara fields of Krýsuvík are near the center of Hafnarfjörður. We saw steaming volcanic vents and boiling hot springs, framed by multi-colored hills. A boardwalk winds through the bubbling and hissing geothermal area, with signage explaining the geology.

Areas like this are national treasures. There are signs saying stay on the paths. It was upsetting to see footprints in some places. Those prints will not go away.

Kryusavik Hot Springs, Iceland 7/20/2021

Vidgelmir Cave

2021-08-162021-08-11Sherry Felix7 Comments

July 19 was titled landscapes of the ring road in our itinerary. We were booked to tour a lava cave at Vidgelmir Cave at 2:00 PM. The tour was led by a tall British lad. That day we covered 962.9 km (598.3 miles). We had to rush to get to the cave in time and we left out seeing Blonduos birdwatching area, Borarvirki basalt strata and ruins, Hvitserkur Rock Stack, Hvammstangi hot springs before the cave, Reykholt historical sight, and Borg a Myrum church and farm after.

Víðgelmir is a lava tube situated in the Hallmundarhraun lava field (formed around 900 AD) in west Iceland, around 2 km southeast of Fljótstunga farm in Hvítársíða, Borgarfjörður. The roof of the lava tube has collapsed, creating two large openings near its north end which are the only known entrances. Víðgelmir is 1585 m long and the largest part of the cave passage is 15.8 m high and 16.5 m wide, making it by far the largest of its kind in Iceland. The cave has a wide entrance but narrows down in some places. An iron gate was installed at the first constriction in 1991 to preserve those of the delicate lava formations or speleothems which hadn’t already been destroyed. Evidence of human habitation, probably dating to the Viking Age, has been discovered in the cave and is preserved in the National Museum of Iceland. Long stretches of the cave floor are very rough and shouldn’t be navigated without a guide. Access and guided tours are provided at nearby Fljótstunga.

Lava tubes are formed when a low-viscosity lava flow develops a continuous and hard crust which then thickens and forms a roof above the molten lava stream. When the eruption subsides, the still-molten lava moving beneath the crust will continue to drain downhill, leaving an open lava tube.Many other lava tubes have been discovered in Hallmundarhraun, most notably Surtshellir and Stefánshellir. (souce: Víðgelmir – Wikipedia)

At one point the guide asked us to turn off the lights and asked for a minute of silence. A few of the tanagers couldn’t do it for a minute and giggled. Interesting how our brains can still see a non existent shadow of our hands.

I kept seeing round hills with nipples on top. I wonder if that is a natural volcanic feature or did the ancients have an erotic sense of humor and place stones on top of the mounds.

nipple on a hill, Bristopar, Iceland 7/19/2021

Myvatn Baths

2021-08-102021-08-11Sherry Felix4 Comments

I didn’t take any pictures so the link will have to do for pictures and information about the Myvatn Baths. Marc said he didn’t want to go but when we there I think he secretly enjoyed it. We had our bathing suits and had to take naked showers before we went in. The water was gloriously warm but there was a smell of sulfur which was a little off putting. We floated in an Infinity pool overlooking the valley. Many people had alcoholic drinks while soaking. We didn’t bother buying anything there. I had to cut the baths short so we only spent an hour and a half there.

Mývatn – Wikipedia tells about the area’s lake, volcanism, birds and flora. We had no time to see that because we had tickets to a boat trip in Hussavic (next post).

Vik

2021-08-022021-08-11Sherry Felix12 Comments

July 15 will take 4 days to cover. We drove south to Vik. The Hotel Katla was just past Vik. The wind was almost gale force and it was raining hard when we arrived at the hotel.

The first picture isn’t a painting it was the view from our room. The wooden plaque hangs in many restaurants in Iceland. The lamb is so tender and sweet. We ate it often while there (See Waterfalls – Sherry Felix – port4u for information about sheep).

After breakfast we went back to black sands beach. It was a treat to see a Black-tailed Godwit – a life bird from the car on the way.

The pretty lupins are found everywhere they should not be. The Nootka lupine was imported from North America in 1945 to combat topsoil loss, which had been a serious problem since the 19th century. The lupine has a tendency to create monocultures which prevents other plants from growing and suffocates more delicate flora. Beauty or Beast? Iceland Quarrels Over an Invasive Plant – The New York Times (nytimes.com).

After the Ice Cave we set off for the boat trip in a Glacier Lagoon. I took pictures along the way (second set of images) as we drove by Katla Geopark (check the Katla link to see all the things there are to see by in Iceland’s largest glaciated area). Also see this brochure about Katla.

Tomorrow I’ll cover the Katla Ice Cave trip that started from Vik.

Hotel Katla view from our window 7/15/2021

Marc at Kalfafell, Southeast Iceland 7/15/2021

Geysir

2021-07-302021-08-15Sherry Felix4 Comments

Geysir (Guide to Iceland) Geysir (Wikipedia) is a huge tourist attraction in the Golden Circle in Southwestern Iceland (coordinates 64°18′49″N 20°17′58″W). We went there on July 14, 2021. It was a very atmospheric with misty rain, clouds in the sky, and lots of steam. There are wonderful colors in the ground and water from the minerals.

Geysir geothermal area is stupendous as you can see by the pictures. It’s very touristy and there are huge buses loads of tourists coming to see it, but I didn’t feel crowded. I had to pop in and see the huge gift shop. We did not need to eat lunch there because I had bought a lovely loaf of fresh baked bread in town the day before and some cheese and butter. I had a collapsible cooler for lunch food for the trip.

The purple Creeping Thyme (Thymus praecox) is called blóðberg in Icelandic meaning bloodstone.