IODP Expedition 320 Moisture and Density

Moisture and density (MAD) data were acquired on ~10 mL sediment or rock samples by measuring three out of four material parameters: wet (saturated) mass, wet volume, dry mass, and/or dry volume after 24 h drying in a convection oven at 105 degrees C. From the moisture and volume measurements, the following phase relationships are calculated: wet and dry water content, wet bulk density, dry bulk density, grain density, porosity, and void ratio. The combination of measurements is defined by the submethod chosen: A, B, C, or D. Wet (A, B, or C) and dry (A, B, C, or D) mass is determined using motion-compensated balances. Wet volume is determined either by helium pycnometry (A) or by the sample's geometric dimensions using calipers (A or D). Dry volume (C or D) is measured by helium pycnometry. Submethods A and B are not recommended by IODP. Submethod C is suitable for saturated materials such as fine-grained sediments. Submethod D is suitable for unsaturated porous material such as certain limestones and basalts.水分与密度（Moisture and Density, MAD）数据集通过对约10 mL的沉积物或岩石样品测定四项参数中的三项获得：湿（饱和）质量、湿体积、干质量，以及经105℃对流烘箱干燥24小时后的干体积。基于水分与体积测量结果，可计算得到以下相态关系参数：干湿含水量、湿体积密度、干体积密度、颗粒密度、孔隙率及孔隙比。测量组合由所选子方法A、B、C或D确定。湿质量（对应A、B或C子方法）与干质量（对应A、B、C或D子方法）均采用运动补偿天平（motion-compensated balances）进行测定。湿体积可通过氦比重瓶法（helium pycnometry，A子方法）或使用游标卡尺（calipers）测量样品几何尺寸（A或D子方法）获取。干体积（对应C或D子方法）采用氦比重瓶法测量。子方法A与B不被国际大洋发现计划（IODP）推荐。子方法C适用于细粒沉积物等饱和多孔材料。子方法D适用于特定灰岩、玄武岩等非饱和多孔材料。