CompuServe Thread

Hi, Steve– Welcome to the forum/section! Being an amateur in these matters, I have no clue. While some of the geologists here may have suggestions, there is no telling how fast the person with an answer may turn up. You might increase your chances of a fast response by asking also in the newsgroup sci.geo.geology; SCIGEO.TXT in this forum's library tells how to access it from CompuServe. Info on another possible source follows. It may help someone make an identification if you give more details. Are you sure it is quartz you see in the rock, rather than mica flakes or some such? Does the rock seem entirely made of these crystals? What is the general color of the rock? Does it have black spots or layers? What town or other landmark are you near? The service announced below can be reached by sending CIS mail to: INTERNET:ask-a-geologist@octopus.wr.usgs.gov Your Internet address (to tell them) is: 75754.2754@compuserve.com Good luck! –Doug "Beginning Monday, October 3, 1994, the USGS will offer a new, experimental Internet service – Ask-A-Geologist. General questions on earth sciences may be sent by electronic mail to the Internet address: ask-a-geologist@octopus.wr.usgs.gov "All electronic mail to Ask-A-Geologist will be routed to the geologist of the day. The geologist will reply to your question within a day or two, or provide referrals to better sources of information. Please include an Internet-accessible return address in the body of your message. "Ask-A-Geologist is an experimental service of the USGS Branch of Pacific Marine Geology, with participation from several other branches. The United States Geological Survey is the principal source of scientific and technical expertise in the earth sciences within the Federal Government. "Naturally, we cannot answer some classes of questions. We cannot answer questions about specific sites — for example, Is my home in a landslide area? We cannot answer questions with a specific economic impact — for example, How much gold is left in the Homestake mine? We cannot endorse commercial products or companies. And, we cannot answer questions based on information not yet released to the public. We might be able to provide referrals to other sources of relevant information. "All questions and answers will be part of the public record. After collecting questions and answers for a few months, we will make a Frequently Asked Questions list (with answers) available via anonymous FTP and World-Wide-Web. "We encourage grade school and high school students with electronic mail access to send in questions — but we can't write your reports for you! In limited testing, we've had an enthusiastic response from many grade school students. "If you have any questions about this service, but not about geology, please contact the system administrator – Rex Sanders <rex@octopus.wr.usgs.gov>.

Steve: I am not a 'field' geologist (i.e. outdoor-type), but if in fact you are seeing quartz grains of sand-size <<several hundred per square inch!>>, I will hazard to say it is probably sandstone. An igneous rock in contact with limestone would (probably) not have suddenly appeared but would have had some boundary-change marked by yet-another kind of rock. Limestone itself can be granular — in the extreme this is called marble — but the change in character you describe supports the above. If you think it's important, you can drop a little dilute muriatic acid (hydrochloric acid — 5% in water is strong enough) on it to exclude this possibility. Limestone will fizz. If only the matrix and not the grains themselves fizz, you *can* have sandstone with limey cement. I'm sure it is possible to split sandstone with explosives, probably just a different technique (deeper/narrower/shallower/bigger plug holes, something). But I have no experience in that; maybe you can find someone who does (once you confirm the identity of the rock). >> is it wide spread or will I run out of it!!! No way I (or anyone, with no more data) can tell the answer to that. I would ask around — any old-timers who might have dug wells in the area, near-by colleges with earth science programs or geological formation maps. While you're at it, take a piece of the rock to the college, or even a high school science teacher, for identification. And try the "ask a geologist" service Doug recommended. For that, it will help if you can get a topographic map of the area and pinpoint your location on it. Sporting goods or hunting stores will sometimes have those maps. Good luck. — E.

Was there a color change associated with the new rock? When you say "specks of quartz", do you mean you see distinct grains of quartz sand, or do you mean the rock sparkles, like a quartzite?

It sounds like you've run into quartzite — a sandstone with the grains tightly welded to each other. That stuff is usually very hard, but brittle. If I were you, I'd contact a local geologist. He/she should be able to figure out where you are in the geological column, what you are dealing with, and how thick your new formation probably is. Might even be able to recommend the best way to break up the rock.