| The UHPM rock slice exposed in the Dabie-Sulu belt provides a natural laboratory for examining the deep parts of the lithosphere and orogenic roots, and has attracted many geoscientists for frontier researches. Geophysical investigations revealed a high-velocity (>6.8km/s), high-density (>3.2g/cm3) and high resistivity (>6000Ωm) layer (3-high body) at depths between 3.2km and 4.3 km in Donghai area, which can be penetrated by a 5000-meter-deep drillhole. Therefore testing the composition and character of this "3-high body" is one of the scientific goals of CCSD project. Petrophysics investigations on the cores from pilot-hole and rocks form the outcrop around the drillsite supplied necessary constrains on the interpretations of geophysical results, and published the direct evidence in establishing geophysical models and interpretation standards for crystalline rocks. Based on the petrophysical measurements on the cores from CCSD 2000m-pilothole and some rocks from the outcrops in Donghai area, especially according to lots of tests and analysis on the elastic and thermal properties of the rocks, the petrophysical properties and their relationship as well as their significances in geology and geophysics are given for different rocks in Donghai area. Possible origins of deep seismic reflection are discussed and the possible composition of 3-high body is given according to the petrophysical results.1. Continuous petrophysical profiles of CCSD 2000m pilothole are established, which gives important constrains on geophysical models and well-logging interpretation.A dataset of densities, seismic velocities (including compressional wave Vp, shear wave Vs, water saturated Vp and Vs) as well as their profile along the depth of 2000m-pilohole are investigated based on the petrophysical measurements under air pressure and room temperature, which supplied the data foundation in verifying different geological and geophysical models. According to the lithological distributions of pilot hole and the requirements of petrophysical studies, all the samples are classified into 7 types: 1-Rutile-bearing eclogite, 2-Phengite-bearingeclogite, 3-Amphibolization eclogite, 4-Strongly retrograde eclogite, 5-Paragneiss, 6-Orthogneiss and 7-Serpentinization garnet Peridotite. The petrophysical properties and their relation to the degree of retrograde, the components of minerals, the temperature and the pressure are discussed and compared for 7 kinds of rocks.2. The characteristics of seismic velocities and their anisotropy of different rocks from pilot-hole are studied. The factors influenced on seismic velocity are discussed and the seismic velocities measurements are performed under high temperature up to 600℃ and high pressure up to 600MPa.About 350 core samples from CCSD 2000m-pilothole are measured on the elastic properties, which shows that among the different rocks, fresh eclogite has the maximum seismic velocity with average Vp=7.86km/s, and the gneiss has the minimum velocity (average Vp=5.53km/s for orthogneiss and 5.71km/s for paragneiss). The retrogression can decrease the seismic velocity of eclogite. The ultra-mafic rocks occurred in pilothole has the Vp velocity varies from 5.96km/s to 6.66km/s. The serpentined garnet-peridotite has the decreased velocity near the level of retrograde eclogite. In the vertical profile, the layers from 100 to 1200m have the high velocity with average Vp=6.37km/s because of the eclogite and ultra-mafic rocks in this layer. From 1200 to 2000 meters are made up of orthogneiss and some eclogites, which induced a lower velocity in average Vp=5.91km/s. The velocities of these 2 layers are consistent with those inferred from geophysical results (Vp≈6.4km/s from 100 to 1200m and Vp≈5.8km/s from 1200 to 2000m).The core samples from 2000m-pilothole have distinct seismic anisotropy under air pressure and room temperature. In average, seismic wave propagates in horizontal direction is faster than that in vertical direction with the anisotropy 7.04%, decreased to 3.92% after w...
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