The Archeological Excavations at Willow Beach, Arizona

Willow Beach, a prehistoric camp site excavated by the National Park Service, is located on a river terrace 15 mi. south of Hoover Dam on the Colorado River. This site was occupied sporadically over many years by several groups of people. It was not the permanent village of a sedentary group. The materials and tools left by the various people who camped at Willow Beach were periodically covered by sediments and silts laid down by the Colorado River during seasons of flood. As a result, the different levels of human occupation were separated by sterile flood deposits, a situation which simplified the task of excavation and interpretation. This site probably existed because any travel between the high plateau area of the Arizona Strip and the Mohave Desert of southern California was channeled by geographical features through a restricted area, and at this point a good campsite happened to be available. This travel lane developed into a trade route which in ceramic times joined with the Mohave-Pacifictrail across southern California. In 1936 the first investigation of Willow Beach was undertaken. An area 40 by 38ft. was excavated to a depth of 9 1/2 ft. by the C. C. C. with M. R. Harrington as collaborator for the National Park Service. The party was in the field from March 18 to April 8, and again from September 8 to November 13, 1936. Nine hundred and twenty-seven specimens were cataloged from these excavations and six human burials and one dog burial were recovered. In a brief report on this work, Harrington (1937, 86-9) indicated that the lower levels were preceramic in content, the projectile points being similar in workmanship to those of the Basketmaker II culture. Above this material was a barren layer averaging 2 ft. in thickness. Resting on this barren layer were 4 ft. of deposits containing pottery and points which he compared to the early Pueblo culture. Near to and on the surface, Paiute points were found, representing the last occupation of the site. During the 1947-48 excavation program of the National Park Service, two additional tests were made under the direction of Gordon C. Baldwin, archeologist at Lake Mead National Recreation Area. One excavation was set down along the northwest face of the 1936 excavations. It was about 25 ft. wide and extended 15 ft. to the northwest to a depth of 8 1/2 ft. A second test about 20 ft. wide was run into the terrace from the river side for a distance of about 15 ft. In his MS. report on this work Baldwin (1948, 67, 70) stated that though there was evidence of stratification, frequently the lines of demarcation between layers were indistinct, due mainly to the soft sand and ash contents of the deposits. The project described in this publication took to the field February 8, and completed operations April 14, 1950. Two tests were conducted in the course of the work. The first was set down and extended to the northwest of the 1947-48 excavations. Cultural material was recovered to a depth of 1.5 m. Below this, tests revealed sterile earth to a depth of 3.5 m. below datum, beyond which no further testing was -conducted. The second test was laid out on the southeast edge of the 1936 excavations and it was here that the great majority of material and information was gathered. Excavations reached a depth of 4 m. in the deepest spot, and, throughout the trench, stratigraphy was clearly evident.威洛比奇（Willow Beach）是一处由美国国家公园管理局（National Park Service）发掘的史前营地遗址，坐落于科罗拉多河沿岸、胡佛水坝以南15英里的河阶地上。该遗址在多年间被多组人群间歇性占用，并非某一定居群体的永久性村落。 在此扎营的不同人群遗留的遗物与工具，会定期被科罗拉多河洪水季沉积的泥沙与粉砂覆盖。因此，不同时期的人类活动层被无文化层的洪水沉积层分隔开来，这一情况简化了发掘与地层解读工作。 该遗址之所以存在，大概率是因为亚利桑那狭长地带的高原区域与南加利福尼亚州莫哈韦沙漠之间的通行路线受地理条件限制，只能通过一处狭窄通道，而此处恰好存在一处优质营地。这条通行通道后来发展为贸易通道，在制陶时代与横贯南加州的莫哈韦-太平洋小径（Mohave-Pacific Trail）相连。 1936年，威洛比奇遗址首次开展考古调查。美国民间资源保护队（Civilian Conservation Corps，CCC）联合受雇于美国国家公园管理局的M·R·哈灵顿，对一处40×38英尺的区域开展发掘，发掘深度达9.5英尺。考古队分别于1936年3月18日至4月8日、9月8日至11月13日两次在野外作业。此次发掘共编目927件标本，出土6座人类墓葬与1座犬只墓葬。哈灵顿在相关工作简报（1937年，第86-9页）中指出，下层遗存属于前陶期，出土的投射尖状器工艺与篮纹二期文化（Basketmaker II culture）同类器物高度相似。该层之上覆盖着平均厚度为2英尺的无文化层。无文化层之上则是厚达4英尺的沉积层，其中包含陶器与尖状器，哈灵顿将其与早期普韦布洛文化（Pueblo culture）进行了比对。在遗址近地表及地表层，考古人员发现了派尤特投射尖状器，代表了该遗址的最后一处人类活动层。 在美国国家公园管理局1947-1948年度的发掘计划中，米德湖国家游乐区考古学家戈登·C·鲍德温主导开展了两处额外的探方发掘。第一处探方紧邻1936年发掘区域的西北侧，宽约25英尺，向西北延伸15英尺，发掘深度达8.5英尺。第二处探方宽约20英尺，从河岸一侧向河阶地内部推进约15英尺。鲍德温在此次工作的手稿报告（1948年，第67、70页）中提到，尽管遗址存在地层堆积证据，但各层之间的分界界线往往模糊不清，这主要是因为沉积物中含有松软的沙土与火山灰。 本出版物所记述的考古项目于1950年2月8日启动野外作业，同年4月14日完成全部工作。本次作业共开展两处探方发掘。第一处探方位于1947-1948年发掘区域的西北侧并向西北延伸，发掘至1.5米深度时出土了文化遗物。在此之下，钻探显示基准面以下3.5米处均为无文化层的土层，因此未再进行更深层的勘探。第二处探方设于1936年发掘区域的东南侧，此处也是本次作业出土绝大多数遗物与考古信息的地点。发掘最深点深度达4米，整个探沟的地层学特征清晰可辨。