PART II GEOLOGIC OBSERVATIONS AND INTERPRETATIONS ALONG THE COAST (continued)
In many ways the geologic story of Second Beach is similar to that of Third Beach. Melange rocks underlie most of the bluff and beach area whereas the headlands both to the south and north are composed of a sedimentary rock sequence of the Hoh rock assemblage. Structural interpretations suggest that the melange rocks of the bluff and beach are a part of a major zone that extends from the Third Beach area behind Teahwhit Head to the south and continues westward along Second Beach nearly to the headland known as Quateata, where it swings northward (fig. 25). Structural trends suggest that the sedimentary rocks of Teahwhit Head, the "Quillayute Needles," and Quateata are large areas of outcrop of the same sequence of rock strata. Furthermore, these headlands and offshore rocks are thought to constitute another segment of the earth's crust that now lies between two major thrust zones, one of which is represented by the melange rocks of the beach and bluff areas of Second Beach. The contact between melange rocks and the sedimentary rock sequence, although largely concealed, lies between the beach and the "Quillayute Needles," and swings onshore immediately southeast of Quateata to the north and just north of Teahwhit Head to the south. A large block of volcanic rock rests on the beach immediately seaward from the end of the trail. Volcanic blocks, although rare in local coastal areas, are "exotic" and are found only in melange rock zones. This large volcanic block and other smaller blocks occurring about half a mile to the south are composed of angular fragments of volcanic rock and some sedimentary rocks that are welded together to form a breccia. White veins of calcite are scattered throughout and represent a period of secondary mineralization that filled fractures once present within the rock mass. HIKING INFORMATION SECOND BEACH AND VICINITY Second Beach is accessible by a formal National Park Service trail about three-quarters of a mile in length from the La Push highway to the northern end of the beach (fig. 45). The beach may be traversed a short distance northward where, at low tide, nearby offshore rocks are exposed. A long narrow headland, where a natural arch has been carved, marks the limits of the passable area (fig. 60). It extends the farthest of several fingerlike projections that form the major headland of Quateata. The origin and meaning of Quateata is apparently unknown, but it is pronounced Qw'aatilla by the Quileute people (Powell, Penn, and others, 1972).
One and a half miles of beach stretch southward along melange rock bluffs from the formal trail. During low tide, the rocky massive sandstone shores of the north side of Teahwhit Head may be traversed to its westernmost point (fig. 61). It was from atop this high narrow point that Coast Guardsmen in 1943 rescued 51 crewmen from the wrecked freighter Lamut (see Historical note on Teahwhit Head Shipwreck).
The rock strata of Quateata can be examined in part from Second Beach, particularly at low tide. Most of these strata, as well as those of the "Quillayute Needles" and Teahwhit Head to the south, are massive sandstone. However, bedded siltstone and sandstone are exposed in the small cove just beyond the first passable headland to the north from the trail. The contorted and broken bedding of the rock strata of this outcrop (fig. 63) spectacularly demonstrates the considerable effect of crustal forces on rock formations. HISTORICAL NOTES SHIPWRECK AT TEAHWHIT HEAD Teahwhit Head (according to Davidson, 1889, Te-ah'whit means "leg" in Chinook jargon), a major irregular headland with high sheer cliffs, craggy seaward projections, and offshore rocks, forms an impassable barrier between Second and Third Beaches (fig. 61). This large outcrop area of Hoh rocks is only one of many treacherous rock outcrop areas along the Washington coast where ships have met their fate. In the spring of 1943, the Russian freighter "Lamut" with a crew of 52 men and women bound for Vladivostok from Puget Sound, encountered a violent storm and went aground between offshore rocks and the sheer cliffs of Teahwhit Head (fig. 62). Accounts attribute the successful rescue that followed to the gallantry, courage, and ingenuity of the men of the U.S. Coast Guard. Because storm conditions prevented a rescue by sea, Coast Guardsmen made their way through several miles of dense underbrush of the coastal forest to reach the knife-edge cliff high above the wreck. It is said that the ridge was so narrow that it had to be literally straddled. Finding that immediate action must be taken or the Russian crew would perish, the rescuers ingeniously tied shoe laces together to form the initial line to the ship. The ship's crew then attached a heavier line which the rescuers hoisted to the top of the cliff and secured. With the exception of one woman, who was lost in an overturned lifeboat when the ship's crew attempted to abandon ship, all remaining 51 members of the crew were rescued. One by one, both men and women climbed upward on the nearly vertical line, dangling over a churning chasm below to a precarious perch, then to safety from Teahwhit Head (Gibbs, 1962).
As a result of DIFFERENTIAL EROSION, an arch or slotlike feature has been formed in the impassable headland to the northwest (fig. 60). Fracturing across this massive sandstone headland has weakened the rock thus allowing the process of erosion to carve an opening in this narrow headland. Another example of DIFFERENTIAL WEATHERING has resulted in the honey comblike structure that is particularly well developed on the surface of the headland to the southeast of the cove (fig. 64). Although the massive sandstone of this small headland appears uniform, it has an unequal weakness to weathering, thus a FRETTED surface has developed.
Southward, in several places, red-colored sands occur on the beach (fig. 65). They usually are prevalent in the vicinity of the trail near small drainages or seeps that flow onto the beach from the bluff. The red coloring of these sands is caused by concentrations of tiny crystals of the relatively heavy red mineral GARNET. Black sand grains of the iron-rich mineral MAGNETITE are frequently found associated with the red garnet sands because they too are a heavy mineral. These HEAVY MINERALS were originally in the Pleistocene or ice age deposits that cap bedrock in this area. They have since been eroded from the Pleistocene deposits and brought to the beach by streams where, because they are relatively heavy, they have been concentrated along the beach by wave action.
The massive sandstone stacks and islets of the "Quillayute Needles" lie directly west of Second Beach and therefore are best viewed from this area (fig. 66). Although modern-day "sea-level platforms" are developed along almost all coastal areas, they are particularly well formed at the base of these offshore rocks. The feature is best observed when the tide is low. It appears as a nearly flat surface skirting most rock masses slightly below the high-tide level. Because bedrock is periodically dampened and dried at this level by fluctuating sea level, its surface is weakened and therefore more easily eroded by the wave action than the continuously damp surface below this level. Furthermore, some stacks are even slightly undercut at or just above the level of the platform (fig. 53). At this level the process of erosion is sometimes more effective than all other parts of the rock exposed to subaerial weathering.
HISTORICAL NOTES THE "QUILLAYUTE NEEDLES" The Quillayute Needle is perhaps the most spectacularly shaped of all the massive sandstone rocks and islets that lie immediately west of the north end of Second Beach. As the southernmost of the group, its needlelike spine rises some 85 feet above sea level and is no more than 35 feet in diameter at the base (fig. 67). Because the name is so vividily descriptive, the entire group of offshore rocks and islets has informally become known as the "Quillayute Needles" (fig. 66).
Other terms are recorded as having been applied to some of the islets and places with in the group. Early records (Davidson, 1889) refer to the outermost large islet as HUNTINGTON ISLAND and describe it as ". . . about 180 yards in extent with nearly vertical sides, flat top, and bare . . ." However, the top of the outermost of these large islets is noticeably sloped. The origin of this name may have been from that of C. A. Huntington, an Indian agent at Neah Bay during the 1870's. More recent data (Alcorn and Alcorn, 1976) state that the Quileute people know the largest and "slanted" islet as Dhuo-Yuat-Zach-Tah, meaning BIRD ROCK. Assuming that "slanting" refers to the islet's top, the description best fits what earlier records refer to as Huntington Island. The term CAKESOSTA is an official place on maps and charts, and according to historians (Powell, Penn, and others, 1972), Kikc'ostal, in the Quileute language refers to CANOE LANDING PLACE. It is not clear if the name is for a general place among the islets or if it possibly refers to the large islet immediately east of Huntington Island or Bird Rock. The ancient and now-elevated, wave-cut sea-level platform, carved during the Pleistocene Epoch, is also well displayed on several islets off Second Beach by flat top surfaces. The trace of this surface can be seen in many other places along the coast, as on Alexander island, (fig. 37) and along many coastal bluffs. In most of these places, the actual surface is covered with a varying thickness of Pleistocene material. However, the "Quillayute Needles" are essentially bare of such surficial material and the surface viewed here is the actual elevated wave-cut terrace, estimated to have been formed some 125,000 years ago (see Deposits and Processes of the Ice Age, Part I). Although partially covered in places with vegetation, melange rocks are almost continuously exposed southward to the massive sandstone cliffs of Teahwhit Head. The bluffs in the southern part of Second Beach are composed largely of incompetent siltstone blocks rather than blocks of sandstone; thus landslides are particularly prevalent in that area. The sudden change from bluffs of slumped melange rocks to cliffs of massive sandstone to the south marks the trace of the fault that separates melange rocks of Second Beach from the sedimentary rock sequence of Teahwhit Head, "Quillayute Needles," and Quateata (fig. 25). A major thickness of this sequence is accessible for examination at low tide along the northwest shores of Teahwhit Head (fig. 61). Most of these rocks are highly fractured massive sandstone (fig. 69). Several thin zones of bedded siltstone and sandstone indicate that the sequence is nearly vertical and trending northwest toward the adjacent bay.
Several archlike features have also been eroded in the Teahwhit Head area. Here again, as at Quateata to the north, they are developed along weakened fracture zones in massive sandstone. The first of these to be encountered southward from Second Beach is a tunnel-like passage through a massive sandstone knob (fig. 69) that lies a short distance seaward from the main cliffs. This tunnel may be reached and examined at low tide. A typical arch has also developed on the westernmost accessible point of Teahwhit Head. As Teahwhit Head is very largely massive sandstone and highly fractured, erosion has developed a very irregular headland with fingerlike, knife-edged projections, irregularly shaped reentrances, and elongated nearby offshore stacks. The northwest structural trend of the sedimentary rocks of Teahwhit Head is grossly reflected by several northwest-trending projections and elongate offshore stacks.
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