介殼灰?guī)r

介殼灰?guī)r（Bioclastic limestone）

產(chǎn)地：山東省新泰市

特征：

生物碎屑灰?guī)r的一種，是以生物碎屑被碳酸鈣膠結(jié)而成的灰?guī)r。生物碎屑含量變化于40%～90%，種類繁多，生物碎屑主要為莊氏蟲的頭甲和尾甲，呈完整形體或碎片，由破碎的生物貝殼被碳酸鈣膠結(jié)而成。膠結(jié)物主要為泥晶或亮晶的方解石，偶含石英與黏土礦物。由于生物碎屑含量與膠結(jié)程度不同，使其物理性質(zhì)變化較大。通常堅韌度比較小、抗壓強(qiáng)度較低、小于100MPa，密度2.3g/cm3，孔隙率大、質(zhì)地比較松。呈生物碎屑結(jié)構(gòu)，塊狀構(gòu)造。結(jié)晶介殼灰?guī)r往往發(fā)育在高能介殼灘中，壓實、膠結(jié)、交代等成巖作用強(qiáng)烈，介殼的原始成分及結(jié)構(gòu)都已發(fā)生明顯變化，以方解石質(zhì)的殼體為特征，介殼間往往為鑲嵌狀、連晶狀含鐵方解石膠結(jié)。

淺湖—半深湖較低能灘相中含有機(jī)質(zhì)泥質(zhì)介殼灰?guī)r是主要的儲集層和產(chǎn)層，單層厚度薄，但累積厚度較大，分布面積廣，常夾于暗色泥頁巖中，源儲一體，更有利于成藏。這類泥質(zhì)介殼灰?guī)r的殼間孔構(gòu)成了主要的儲集空間，殼間孔平行于殼體的長軸方向排列，并常見黑色有機(jī)質(zhì)充填。

采集人：陳勇、顏世永、裴仰文、王健、段忠豐

Bioclastic limestone

Provenance: Xintai, Shandong, China

Characteristics:

In limestone rocks there are different types of possible bioclasts, depending on the region, time and the climate during the formation stage. Skeletal fragments: this type of limestone texture can be found as whole micro-fossils, whole large fossils or broken up fragments of larger fossils. This is the most common texture. The kinds of skeletal particles present depend upon the age of the rock and the paleo-environmental conditions from the time they were deposited. With these different types of fossils, certain ones will be more dominant in a certain rock compared to others. Trilobite skeletal fragments.

The climates and wave conditions play a role on the formation of skeletal fragments by that organisms like branching forms of bryozoan are fragile and are not found in high wave energy environments. Found in limestone units that have been deposited under quite less active water conditions.

Gatherers: Chen Yong, Yan Shiyong, Pei Yangwen, Wang Jian, Duan Zhongfeng