Part 2

The Devil’s Den Trail leads down the east side of Burke Mountain from the observation tower at the summit. This trail is rather poorly marked past a certain point, but if you wish to strike off on your own and see some wonderful country, a hike down this trail with a swing to the north will bring you back to the summit road.

The several ski trails on Burke Mountain are all walkable during the summer, but they will not appear as smooth as when covered with snow, and the trip down will take considerably longer on foot than on “boards.” The Bear Den Ski Trail is especially good for geological sightseeing.

NEARBY AREAS TO VISIT

While at Darling State Park a visit to Lake Willoughby is well worth the trip (Figs. 19, 20). A glance at Figure 1 will show you its general location. Once you visit this lake, you might ask “why so beautiful a Lake Willoughby?” There is still some question as to the origin of the lake basin, but a combination of oriented joints and recent glacial movement seems to fit the picture. Deeper and faster weathering along parallel joints together with glacial movement and scour in the same direction as the joints probably dug the elongated trench which, when filled with water, became Lake Willoughby.

It is hoped that this pamphlet has given you the desire to enlarge your knowledge of the science of geology. Geology is all around you wherever you might travel and a knowledge of geology will open new roads even while traveling old ones. Here’s luck to you in your travels; try to _see_ what you look at.

Granite-Metamorphics Observation Tower Burke Summit Rd. Bear Den Trail Fire Trail Park Boundary Contour Line Dip and Strike: Bed Dip and Strike: Bed? Dip and Strike: Joint

SUGGESTED READING

Leet, L. Don and Judson, S., 1965, _Physical Geology_, 3rd Edition, Prentice-Hall, Inc., Englewood Cliffs, New Jersey. This is a starter for the geology student.

Dunbar, C. O., 1959, _Historical Geology_, John Wiley and Sons, New York. Also a beginning book, read after above book.

Dennis, John G., 1956, _The Geology of the Lyndonville Area, Vermont_, Vermont Geological Survey Bulletin 8. This is for the more advanced student and relates the geology of the area adjacent to Burke Mountain and Darling State Park.

Jacobs, Elbridge C., 1941-42, _The Great Ice Age in Vermont_, Report of the State Geologist, Vol. 23; pp. 27-47.

Stewart, David P., 1961, _The Glacial Geology of Vermont_, Vermont Geological Survey, Bulletin No. 19.

Woodland, B. G., 1963, _A Petrographic study of Thermally Metamorphosed Pelitic rocks in the Burke Area, Northeastern Vermont_, American Journal of Science, volume 261, pages 354-375. For the advanced student.

Woodland, B. G., 1965, _The Geology of the Burke Quadrangle, Vermont_, Vermont Geological Survey Bulletin No. 28. This is a comprehensive study of the Burke Mountain area and a must for those interested in Darling State Park.

Footnotes

[1]The granite found in Darling State Park is white or pinkish in color and most times is speckled with shiny black mica flakes. On close inspection, grains of smoky to clear color are seen within the rock. The white and pink grains are the mineral, feldspar; the shiny black flakes, biotite mica; the smoky to clear grains, quartz or silica. A magnified picture of a slice of granite (see Fig. 2) shows the individual mineral grains and their interlocking nature with each other. Granite belongs to a major family of rocks, termed _Igneous rocks_. Igneous rocks are formed through the hardening or lithification of molten rock-material when subjected to the cooler temperatures at or near the earth’s surface. The molten rock material formed at some depth beneath the surface of the earth, where temperatures were many hundreds of degrees hotter than at the surface.

[2]Metamorphic rocks are either sedimentary (this, a third major family of rocks which is characterized by a layered appearance that has been retained by many of the altered park rocks) or igneous rocks (the granite) which have been under the influence of pressure, heat, and chemically active fluids, oftentimes resulting in chemical and structural changes. Most of the metamorphic rocks seen in the park are either schist, phyllite, slate or quartzite. For the benefit of the more advanced student, the rocks of the park area are considered a granite-hornfels complex (see Bertram G. Woodland’s paper of 1963, “A Petrographic study of Thermally Metamorphosed Pelitic rocks in the Burke Area, Northeastern Vermont,” in the American Journal of Science, volume 261, pages 354 to 375).

[3]Sedimentary or layered rocks, the third major rock family, are composed of pieces, grains and other materials from older metamorphic, igneous and sedimentary rocks. These fragments have been carried by rivers and streams to some resting place at the bottom of a sea, lake, or stream channel. This mud, sand and gravel, under the weight of steadily increasing overburden, and the presence of cementing materials, slowly hardened into rock which we now call limestone shale, sandstone, and conglomerate.

[4]A geologic formation consists of a sequence of rock layers which were deposited under essentially the same conditions, or a series of alternating conditions, and which can be easily distinguished and mapped as a unit by geologists in the field.

[5]Geologic time is divided into four Eras which are designated from oldest to youngest: Precambrian, Paleozoic, Mesozoic, and Cenozoic. Each of these Eras is divided into geologic periods of time. The Devonian Period is in about the middle of the Paleozoic Era and began some 330 million years ago and ended approximately 290 million years ago (see Geologic Time Scale, Fig. 14).

[6]A joint is a break in a rock mass which interrupts its physical continuity. A group of more or less parallel joints is known as a joint set.

Transcriber’s Notes

—Silently corrected a few typos.

—Retained publication information from the printed edition: this eBook is public-domain in the country of publication.

—In the text versions only, text in italics is delimited by _underscores_.