冀西北地区重力场特征及对地质构造的再认识

依据冀北地区1:20万区域重力调查成果,阐述了冀西北地区区域重力场的基本特征,在对该地区断裂构造推断解释的基础上,提出了对该区主要构造的新认识.其中依据重力资料新推断出3条北西向断裂构造:康保-赤城-密云断裂F₁₁、张北-张家口-怀来-昌平断裂F₄₇、万全榆树林-涿鹿倒拉咀断裂F₄₈;认为东西向康保-沽源、崇礼-赤城、天镇-密云深大断裂带,北东向张北-沽源、怀来-上黄旗、北西向兰城子-龙门所、张北-沙河、榆林沟-南流水断裂带构成了本区内深部断裂的构造格架.

CHARACTERISTICS OF THE REGIONAL GRAVITY FIELD IN NORTHWEST HEBEI AND THEIR SIGNIFICANCE TO GEOLOGICAL TECTONICS

Based on an investigation into 1:200 000 regional gravity field in northwest Hebei, this paper deals with characteristics of the regional gravity field and, according to inference and interpretation of regional fault structures, puts forward some new understanding concerning the main structures. The three NW-trending faults, namely, Kangbao-Chicheng-Miyun fault (F₁₁), Zhangbei-Zhangjiakou-Huailai-Changping fault (F₄₇) and Wanquanyulingou-Zhuoludaolazui fault (F₄₈), were recognized on the basis of gravitational and magnetic information. The EW-trending Kangbao-Guyuan, Chongli-Chicheng and Tanzhen-Miyun faults, NE-trending Zhangbei-Guyuan and Huailai-Shanghuangqi faults, and NW-trending Lanchengzi-Longmensuo, Zhangbei-Shahe and Yulingou-Nanliushui faults constitute deep fractural framework of this area.