英语翻译This short overview of classifications illustrates thatthey are either incomplete,difficult to apply in the fieldor include overlapping definitions.Consequently,mostauthors have grouped structures into morphologicalcategories (e.g.,Rosset

英语翻译This short overview of classifications illustrates thatthey are either incomplete,difficult to apply in the fieldor include overlapping definitions.Consequently,mostauthors have grouped structures into morphologicalcategories (e.g.,Rosset
英语翻译
This short overview of classifications illustrates that
they are either incomplete,difficult to apply in the field
or include overlapping definitions.Consequently,most
authors have grouped structures into morphological
categories (e.g.,Rossetti,1999; Rossetti and Goes,
2000; Rodrı´guez-Pascua et al.,2000) or into a mixture
of morphological and genetic categories (e.g.,Alfaro et
al.,1997).
In the Zarzal Formation,most of the soft-sediment
deformation structures reported by Lowe (1975),
Mills (1983) and Owen (1987,2003) can be observed.
However,some complicated structures could
not be related precisely to a classification.Consequently,
the structures will first be described morphologically
and grouped into four groups,further
subdivided into 14 categories (Fig.6).Subsequently,
the processes potentially associated with their genesis
will be discussed.
4.Soft-sediment deformations in the Zarzal
Formation
Soft-sediment deformation structures in the Zarzal
Formation are encountered mainly in the region between
Cartago and Ansermanuevo (Fig.4).Although
the most frequently deformed lithologies are fine to
medium-grained tuffaceous sands and clays,deformations
are present in other lithologies,including diatomites
and tuffaceous gravels.The following types of
structures have been observed (Fig.6).
4.1.Load structures
4.1.1.Load casts
The classification used here follows essentially that
proposed by Owen (2003).Load casts are the most
frequent structure encountered in the studied area.Although
the term bcastQ is inadequate,because the structure
cannot really be associated with a cast,the term is kept in order to avoid confusion in the nomenclature.
Both categories proposed by Owen (2003) have been
encountered.
4.1.1.1.Simple load casts.Their size varies from
centimeters to meter.They occur in different lithologies,
but mostly in tuffaceous sands and gravels overlying
silty clays and diatomites (Fig.7A).They show a
concave profile and slightly penetrate into the underlying
bed.Laminations are usually gently deformed,
although in some cases this structure appears associated
with more pronounced deformation,such as convolute
lamination and water escape structures (Fig.7A).It is
similar to the bsagging load castQ of Alfaro et al.
(1997).
4.1.1.2.Pendulous load casts.Their size fluctuates
from a few up to 50 cm (Fig.7B).They occur in
various lithologies but,similarly to the simple load
casts,they are more frequently encountered in tuffaceous
sands and gravels overlying clays and diatomites.
Occasionally,such deformations may be observed in
fine-grained sands overlying medium to coarse-grained
sands.Their shape is very variable:generally they
become narrower upwards (Fig.7B),but this is not
always the case (Figs.7C and 8A).They show features
similar to the bdrop structuresQ of Anketell et al.(1970).

英语翻译This short overview of classifications illustrates thatthey are either incomplete,difficult to apply in the fieldor include overlapping definitions.Consequently,mostauthors have grouped structures into morphologicalcategories (e.g.,Rosset
这短暂的概要说明的分类
他们要么是完整的,很难适用于这个领域
或有重叠的定义.因此,大多数
作者把构造成形态
类别(如·罗塞蒂,1999;·罗塞蒂又去了,
2000年,Rodrı之guez-Pascua等,2000)或混合
形态与遗传类(例如,Alfaro等
,1996).
在Zarzal形成,大部分的soft-sediment
变形结构由劳(1975),
米尔斯(1983)和欧文(1987)可以被观察到.
然而,一些复杂的结构
不相关的精确到一个分类.因此,
首先将描述的结构形态上
与划分为4个组,进一步探讨的问题
分为14类(图6).随后,
这个过程可能与他们的起源
将被讨论.
4.在Zarzal Soft-sediment变形
形成
在Zarzal Soft-sediment变形结构
形成了主要在地区之间
Cartago和Ansermanuevo(图4).虽然
最常见的岩石的变形,你可以继续
medium-grained tuffaceous金沙和粘土、变形
存在于其他岩石,包括diatomites吗
和tuffaceous砾.以下类型的
结构已经观察(图6).
41.负载结构
4.1.1).负荷铸
使用此分类的本质
提出通过欧文(2003).负荷投是最
频繁的结构,对研究区中.虽然
这个词是不够的,因为bcastQ结构
不能真的会投,是为了避免混乱的术语.
这两个奖项的提议,欧文(2003)
遇到.
4.1.1.1.简单的负荷.他们的大小不等
厘米平方米.他们出现在不同的岩石,
但是大部分在tuffaceous金沙和砾石覆盖
粉质粘土和diatomites(图7A).他们展示了
凹型和渗透潜在的
床上.通常轻片变形,
虽然在某些情况下,这种结构相关
与越来越明显,如convolute变形
纹理和水逃跑结构(图7A).它是
类似的bsagging负荷castQ Alfaro等.
(1997).
4.1.1.2.摇摆的负荷.其大小波动
从几多达50厘米(图7B).他们出现在
但是,类似于各种岩石的简单的负荷
铸,他们更经常遇到的tuffaceous
金沙和砾石覆盖粘土和diatomites.
有时候,这样可以观察到的变形
覆盖介质的粗粒度的沙滩
沙滩.他们的身材很变量:一般来说,他们
向上缩窄(图7B),但是这不是
总是如此(无花果.7C和8A).他们显示功能
类似的bdrop structuresQ Anketell等.(1970).