Reference lines, fault classification, transform systems and ocean-floor spreading: discussion

Wellman (1971) has presented erroneous data relating to lineaments in Papua New Guinea. The main faults and folds in Papua New Guinea as determined by ground and remote sensing surveys by the Bureau of Mineral Resources, the Geological Survey of Papua New Guinea and by oil exploration companies are shown on the new BMR - GSPNG 1:1,000,000 Scale geological map of Papua New Guinea.

Wellman (1971) in a recent issue of this journal produced an account of fault systems in the Pacific region. However, his Figure 5and related text (p.205) cannot go unchallenged in so far as they refer to the eastern part of the island of New Guinea, i.e., Papua New Guinea.

An example of the inaccuracy of Figure 5 (Wellman, 1971), is the omission of major faults such as the Owen Stanley Fault (Fig.1) and the Frieda Fault (Fig.2), and the depiction of a non-existent major fault system (which he called the New Guinea Fault).

Exhaustive examinations of airphotos, both vertical and oblique, at scales from 1:20,000 to 1:80,000, and of side-looking airborne radarimagery, by numerous officers of the Bureau of Mineral Resources and theGeological Survey of Papua New Guinea during the last 5 - 10 years have failed to detect the lineations shown by Wellman. Furthermore, these studies, and extensive field mapping by government and oil exploration company geologists over the last 25 years, have revealed the existence
of the fault and fold systems shown here in Figures 3a and 4.

Although a strike slip type of movement is suspected for some of these faults only vertical movements have been proved. Thus the sinistral movement claimed for the imagined "New Guinea Fault" should not be regarded as typical of the fault system of Papua New Guinea.

Wellman（1971）提出的关于巴布亚新几内亚线性构造（lineaments）的资料存在错误。由矿产资源局（Bureau of Mineral Resources, BMR）、巴布亚新几内亚地质调查局（Geological Survey of Papua New Guinea, GSPNG）以及石油勘探公司通过地面调查与遥感解译确定的巴布亚新几内亚主要断裂与褶皱，已被标注于新版BMR-GSPNG巴布亚新几内亚1:100万比例尺地质图中。

Wellman（1971）在本刊近期一期中阐述了太平洋区域断裂系统，但就其涉及新几内亚岛东部（即巴布亚新几内亚）的内容而言，其图5及相关正文（第205页）的论述难以被认可。

图5（Wellman, 1971）的不准确之处之一，便是遗漏了欧文斯坦利断裂（图1）与弗里达断裂（图2）等重大断裂，同时虚构了一个被其称为“新几内亚断裂”的不存在的大型断裂系统。

过去5至10年间，矿产资源局与巴布亚新几内亚地质调查局的多名工作人员对比例尺介于1:20000至1:80000的垂直与倾斜航空照片，以及侧视机载雷达影像开展了详尽核查，均未发现Wellman所标注的线性构造。此外，这些研究以及过去25年间政府与石油勘探公司地质学家开展的大量野外填图工作，均证实了本文图3a与图4中所展示的断裂与褶皱系统确实存在。

尽管推测部分此类断裂存在走滑运动，但目前仅证实了垂直运动。因此，针对该虚构的“新几内亚断裂”所提出的左旋运动，不应被视为巴布亚新几内亚断裂系统的典型特征。