Kazumura Cave is a lava tube on the island of Hawaii. The cave formed between four and six centuries ago, when a vent on the east side of Kilauea Caldera erupted, sending lava down the northeast flank of the volcano. As these lava flows advanced, they cooled from the outside in. This produced a hard crust around the flow, which protected the lava from cooling too quickly. (Hawaiian lavas erupt at approximately 2165°F (1185°C). The air and ground temperature is therefore cold to lava.) In time, this protective crust thickened and confined the flow to an oval or rounded conduit referred to as a lava tube.
Lava tubes which are active for long periods of time, can be enlarged by lava flowing through the tube. Lava is a very abrasive fluid which can erode the surround rock. Given enough time and favorable conditions, this erosion can form canyons and lava falls. Erosion can also expose gaps in the existing bedrock. Lava injected into these gaps sometimes remains molten, and later drains back into the tube to form lava straws or runs.
If during an eruption, a hole develops in the ceiling of a lava tube, that hole is called a skylight. Skylights allow heat to escape while admitting cold air. Any time the lava level in the tube drops, cold air entering a skylight can chill the surface of the flow causing a second crust to form. This produces what is known as a tube in tube. Cold air can also crack hot rock, allowing sections of the tube walls and ceiling to collapse, producing breakdown.
A dropping lava level also allows lava sticking to the ceiling to sag and form lavacicles, (a feature similar in appearance to a stalactite). As the lava level drops further, the tube begins to drain and cool. The last bit of lava flowing over a fall has cooled to a putty like consistency and begins to pile up on itself. This forms an irregular column called a dribble spire. At the base of a fall, a thick crust forms on the plunge pool surface, and then sags as lava drains from beneath. The last tubes in tube, also begin to collapse without lava to support their weight.
It can take years for a lava tube to cool sufficiently to support life. As many cave creatures are dependant upon plants for their food, it is likely the cave is not fully colonized until after these plants have become established on the surface above.
Kazumura Cave is just one of several lava tubes that formed in that eruption, but it is by far the most important. As the worlds longest known continuous lava tube, Kazumura is a national treasure that is virtually unknown to all. Geologically speaking, Kazumura has been called a master lava tube. Nearly every type of feature found in a lava tube can be found in this cave.
So, if you’re planning a trip to the big island or already here, and would like to visit Kazumura Cave, call during business hours to schedule a tour.
All tours begin with a short walk through the Puna Rain Forest before descending a ladder and entering the cave. Shortly after entering you will be shown delicate gypsum crystals, which can be damaged by a single drop of water. Moving on a little ways, the passage abruptly ends. Two more ladders must be descended to reach the main passage 20 feet below. At this point the Lava Falls and Pit Room Tours head up slope. After a short search for cave spiders the group moves on to the Lava Falls, four of them, each with their own special features and ranging in height from 5 to 16 feet. Above the fourth Lava Fall is a room decorated with lavacicles, straws, dribble spires, and more. After seeing a few more features the Lava Falls tour turns around.
Tour continues on from here. On the way to the Pit Room you will see more decorated ceilings, ascend 2 lava cascades, and pass through the snake canyon; but be prepared to clamber over rubble. The highlight of the trip is a feature which is so intricate that it is hard to believe that it is made of rock. After seeing the sights at the pit room, the group turns around and heads back.
After descending into the main passage, the Maze Tour heads down slope toward Eureka Falls and the Sexton Maze. On the way is Mongoose Falls. Here the group must climb down a 10 foot drop. Next comes Eureka Falls, which is 37 feet straight down. After checking out the drop it’s time to put on your gear and rappel down (single rope). Further down slope is Red Column Falls, here the tour turns around. The Sexton Maze is then entered by ascending a ladder. After crawling through the maze for about an hour, the group rappels back into the main passage, a 30 foot drop (double rope). It’s now time to ascend Eureka Falls and head back.
If you are: extremely claustrophobic, afraid of being underground, afraid of the dark, have a paralyzing fear of heights, afraid of ladders, or extremely uncomfortable about being locked in, you should avoid these tours.
One sentiment often expressed by visitors on cave tours is: I never imagined that a lava tube could be so interesting. The lava can take on so many different forms. It’s absolutely amazing.
Lava tubes do indeed possess an incredible diversity of features. As the guide at Kazumura, I try to show visitors as many features as possible and explain their formation.
After tours I would often hear: “You have given us so much information, I don’t think I can remember everything. Is there anyplace where all this information is written down?”
To this I would answer, “No, not that I’m aware of.”
After a while folks started saying: “You should write a book.
Because so many of you folks have considered me qualified for such an undertaking, I decided to take your advice. The book is titled “UNDERSTANDING LAVA TUBES AND LAVA CAVES
The book covers the two methods of lava tube formation, and various erosional processes. It looks at how air can color the rock and help shape delicate cave features. There’s a chapter which looks at the various types of lava formations and explains how they form. The book also provides information about other types of lava caves, and their formation. In addition to this, practical information about lava tube caving, and preservation, is provided. And there is a question section, which I have used to provide information that did not easily fit in the text. (Book reviews)