Lava field

A lava field, also called a lava plain or lava bed, is a large expanse of nearly flat-lying lava flows. Such features are generally composed of highly fluid basalt lava, and can extend for tens or even hundreds of miles across the underlying terrain. The extent of large lava fields is most readily grasped from the air or in satellite photos, where their typically dark, nearly black color contrasts sharply with the rest of the landscape.

Hell's Half Acre Lava Field, Idaho, United States of America.
Barren waste of lava fields at Reykjanes Peninsula, Iceland.
Degassing Holuhraun lava field with fountaining at crater Baugur, Iceland, Sept. 2014

According to the US Geological Survey, monogenetic volcanic fields are collections of cinder cones, and/or maar vents and associated lava flows and pyroclastic deposits. Sometimes a stratovolcano[1] is at the center of the field, as at the San Francisco Volcanic Field in Arizona.

Some of the most ancient geological remnants of basaltic plains lie in Canada's Precambrian Shield. Eruption of plateau lavas near the Coppermine River southwest of Coronation Gulf in the Arctic, built an extensive plateau about 1200 million years ago with an area of about 170,000 km2 (66,000 sq mi), representing a volume of lavas of at least 500,000 km3 (120,000 cu mi). The lavas are thought to have originated from a mantle plume center called the Mackenzie hotspot.

Notable examples
gollark: Yes, thanks TIOpy?
gollark: ```python#!/usr/bin/env python3import subprocess, os, os.path, sys, argparse, datetimetimestamp = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")print(timestamp)parser = argparse.ArgumentParser(description="do backups, probably")parser.add_argument("--encrypt", "-E", help="store backup in encrypted folder (please make sure it's unlocked)", action="store_true")parser.add_argument("--no-incremental", "-n", help="don't do incremental backup", action="store_true")parser.add_argument("--save_as", "-a", help="back up under different name")parser.add_argument("dir", help="directory to backup")args = parser.parse_args()incremental = not args.no_incrementalprint(args)srcdir = os.path.abspath(args.dir)outdir = os.path.join(os.path.dirname(os.path.abspath(sys.argv[0])), "encrypted/backups" if args.encrypt else "backups")safepath = (args.save_as or srcdir).lstrip("/").replace("/", "-").replace("_", "-")outpath = os.path.join(outdir, f"{safepath}_{timestamp}{'_incr' if incremental else ''}.tar.zst")snapshot = os.path.join(outdir, f"{safepath}.snapshot")snapargs = ["-g", snapshot] if incremental else []print(srcdir, outdir, outpath)tarproc = subprocess.Popen(["tar", "-c", "-v", "-C", os.path.dirname(srcdir), os.path.basename(srcdir)] + snapargs, stdout=subprocess.PIPE)zstproc = subprocess.Popen(["zstd", "-10", "-T0", "-o", outpath], stdin=tarproc.stdout)def assert_proc(x): if x.wait() != 0: print(f"warning: {x.args} failed")assert_proc(tarproc)assert_proc(zstproc)```efficiency™
gollark: Wow, I really love having to use `grep` to find an option in `--help`!
gollark: Yes.
gollark: Anyway², I'll switch over my backup stuff and use the existing incremental tar thing for smallish compressible directories and rsync for large-scale apiary data.

See also

References
  1. "Volcanic Fields". Retrieved 2014-01-26.
  2. "Boring Lava Field". Archived from the original on 2012-02-07. Retrieved 2014-01-26.
  3. "Harrat Rahat". Retrieved 2014-01-26.
  4. "Lava Trail System - Hell's Half Acre". Archived from the original on 2014-02-01. Retrieved 2014-01-26.
  5. "Reykjanes Peninsula". Retrieved 2014-01-26.
  6. "Lava Plateaus". Retrieved 2014-01-26.


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