Geologically Hazardous Areas

The GEOHAZARDS feature class is a union of the DNR & Natural Resource Conservation Service's (SCS) 1980 Soil Survey for Kitsap County and the soil STABILITY classification from the 1979 "Quaternary Geology and Stratigraphy of Kitsap County" thesis work by Jerald Deeter. The original Stability coverage was obtained by digitizing the "Slope Stability Map of Kitsap County" from the Deeter thesis. This work was performed by Kitsap County GIS. Accuracy and precision standards used for digitizing are unknown. Spatial accuracy is fairly good at small scales, however, accuracy diminishes as the scale increases. Horizontal displacement is quite noticeable along shorelines when comparison of physical features such as estuaries and peninsulas are observed along side imagery. Displacement ranges between 60 to 200 feet at different locations. The DNR/NRCS soil survey mapping project was originally published on paper maps in 1980. The mapped soil delineations were digitized by DNR and transferred into the DNR GIS system in 1998. Spatial accuracy of the original soils coverage is quite good and can be used at medium scales. However, displacement is noticeable in some areas along shorelines and varies in degree. Limitations of this data set are multiplied due to the spatial accuracy and constrains of the originating data layers. This data set is useful for general area characteristics at medium to small scales (on large geographical areas), but not for characteristic determinations at large scales (on small and site specific geographical areas). This Layer is a subselection of the orginal data set, the selection criteria used on the attributes varied. For Geologic Hazardous Areas the selection was- "STABILITY = 'U' OR STABILITY = 'Uos' OR STABILITY = 'Urs' AND SLOPE_MIN >= 30". For Geological Areas of Concern with slopes >15% w/springs & groundwater the selection was- "IDENTIFIER = 3 OR 16 OR 25 OR 41 OR 53 OR 57 OR 61" For Geological Areas of Concern with Highly erodible/potential of high erodibility the selection was- "STABILITY = 'S' AND IDENTIFIER = 3 OR 10 OR 17 OR 21 OR 25 OR 26 OR 27 OR 31 OR 46 OR 48 OR 53 OR 54 OR 9 OR 13 OR 16 OR 20 OR 30 OR 36 OR 41 OR 47 OR 57 OR 61" For Geological Areas of Concern with Intermediate Slope Stability the selection was- "STABILITY = 'I'" For Geological Areas of Concern with Unstabel slopes < 30% the selection was- "STABILITY= 'U' OR 'Uos' OR 'Urs' AND SLOPE_MIN < 30" **This data cannot and may not be used for or relied upon for site-specific evaluations, nor as a substitute for a field survey. - NOTE: The original Deeter work contained an "Io" stability value, which was a subcategory of Intermediate slopes. This subcategory was created and used by Deeter for those Intermediate slopes that were in excess of 30 percent grade which, at the time, had applicable on-site sewage disposal system restrictions per WAC 248-96 (Deeter). As these regulations no longer apply, the "Io" subcategory was removed, leaving all Intermediate slopes under the Intermediate (I) stability value. -GEOHAZARDS要素类是华盛顿州自然资源部（Department of Natural Resources，DNR）与美国自然资源保护服务局（Natural Resource Conservation Service，NRCS，原简称SCS）1980年为基特萨普县编制的土壤调查数据，以及杰拉尔德·迪特（Jerald Deeter）1979年学位论文《基特萨普县第四纪地质与地层学》中的土壤稳定性分类结果的联合数据集。 原始稳定性图层由迪特论文中的《基特萨普县斜坡稳定性地图》数字化而来，该项数字化工作由基特萨普县地理信息系统（Geographic Information System，GIS）团队完成。数字化作业所采用的精度与准确度标准现已无从考证。该数据集在小比例尺下空间准确度尚可，但随比例尺增大，准确度会逐步降低。将河口、半岛等自然地物与影像对比时，可明显观察到海岸线沿线存在显著水平位移，不同点位的位移幅度介于60至200英尺之间。 DNR/NRCS土壤调查制图项目最初于1980年以纸质地图形式发布，其绘制的土壤图斑边界于1998年由DNR完成数字化并导入DNR的GIS系统。原始土壤图层的空间准确度良好，可适用于中比例尺制图，但部分海岸线区域仍存在可见位移，且位移程度存在区域差异。由于原始数据图层的空间准确度与自身限制，本数据集的应用局限性被进一步放大。本数据集适用于中、小比例尺下的大地理区域通用特征分析，不适用于大比例尺下的小范围或特定场地的特征判定。 本图层为原始数据集的子集，其属性筛选规则如下： 1. 地质灾害区域：筛选条件为STABILITY = 'U' 或 STABILITY = 'Uos' 或 STABILITY = 'Urs' 且 SLOPE_MIN ≥ 30； 2. 含泉水与地下水且坡度>15%的地质关注区域：筛选条件为IDENTIFIER = 3 或 16 或 25 或 41 或 53 或 57 或 61； 3. 高易侵蚀/潜在高易侵蚀的地质关注区域：筛选条件为STABILITY = 'S' 且 IDENTIFIER = 3 或 10 或 17 或 21 或 25 或 26 或 27 或 31 或 46 或 48 或 53 或 54 或 9 或 13 或 16 或 20 或 30 或 36 或 41 或 47 或 57 或 61； 4. 中等斜坡稳定性的地质关注区域：筛选条件为STABILITY = 'I'； 5. 坡度<30%的不稳定斜坡地质关注区域：筛选条件为STABILITY = 'U' 或 'Uos' 或 'Urs' 且 SLOPE_MIN < 30。 **本数据不得用于特定场地评估，亦不得替代野外调查。** 备注：迪特的原始研究中包含「Io」稳定性分类项，该分类属于中等坡度的子类别，特指坡度超过30%、当时受WAC 248-96号法规约束的现场污水处理系统限制区域。由于该法规现已失效，「Io」子类别已被移除，所有中等坡度均归入中等（I）稳定性分类中。